"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

On Tue, 28 Feb 2012 19:29:17 -0600, Ignoramus14054
wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

Yes, that's possible. But electronic ignition systems and EFI are
computer controlled. Unless they get all their ducks in a row, things
don't work properly. Get the manual, get the test equipment and let
us know what you find. Or have a tech drop by with same and let you
know.

--
....in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin

Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.

Ignoramus14054 wrote:


1) Lack of fuel pressure
Possibly the wrong fuel pump. I would expect this TBI needs
something close to 50 PSI at the minimum.
2) Lack of voltage supplied to the TBI.

Maybe not. The computer probably sends short pulse-width
modulated pulses of 12 V to the injectors. If the starter
isn't too noisy, you should be able to hear it clicking
when you crank. You can definitely hear the injectors on
most injection systems (but maybe not with the starter
running).
I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).
Maybe, should be relatively easy to check. Yes, could be a bad
ground. The fuel pump is probably not controlled by much electronics.
There may be a fuel pump cutoff relay, but that usually is on
cars with airbags. But, I'd measure the fuel pump pressure.
Somewhere there ought to be a spec on fuel pump pressure. A
quick test just with a gauge connected to the pump would tell you
whether you are getting 10 PSI (carb pump) or 50 PSI (FI pump).

The injectors may be working perfectly, but with no fuel pressure,
the computer is applying short pulses that SHOULD be right at
the higher pressure.

Also, since the pressure regulator made a difference, it may show
that the regulator has a ripped diphragm, crud under the seat or
some other malfunction. Actually, a typical regulator would
set lower pressure without the spring. But, this one might not
be typical.

Jon

On 2012-02-29, Pete C. wrote:

Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.

Yes. The pressure regulator looks OK, in fact, there is not much that
could go wrong with it, and it looks like there is nothing wrong with
it.

i

On 2012-02-29, Pete C. wrote:

Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.

Pete, what sort of a manual would you recommend, I can shell out some
$$$, not only to save money on repairs, but to learn something.

Repair manual or what is it called?

i

On 2012-02-29, Larry Jaques wrote:
On Tue, 28 Feb 2012 19:29:17 -0600, Ignoramus14054
wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

Yes, that's possible. But electronic ignition systems and EFI are
computer controlled. Unless they get all their ducks in a row, things
don't work properly. Get the manual, get the test equipment and let
us know what you find. Or have a tech drop by with same and let you
know.


Larry, what sort of manual would you suggest?

On Tue, 28 Feb 2012 21:25:33 -0600, Ignoramus14054
wrote:

On 2012-02-29, Larry Jaques wrote:
On Tue, 28 Feb 2012 19:29:17 -0600, Ignoramus14054
wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

Yes, that's possible. But electronic ignition systems and EFI are
computer controlled. Unless they get all their ducks in a row, things
don't work properly. Get the manual, get the test equipment and let
us know what you find. Or have a tech drop by with same and let you
know.


Larry, what sort of manual would you suggest?

The Chevrolet Truck service manual, Ig. Maybe eBay?
http://www.ebay.com/sch/i.html?_nkw=...+repair+manual

The dealership are way too damned proud of their manuals, wanting
several hundred dollars for them.

Second choice would be a Mitchell manual for the truck. We used them
for all repair work when I was a mechanic at non-dealer sites. They're
great! (Not cheap.) Try this link. (unknown to me)
http://www.mitchell1.com/M1Products/...uck/index.html

There's apparently some service recall on diesel injectors.
http://tinyurl.com/7xw8s9e

G'luck!

--
....in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin

On Tue, 28 Feb 2012 21:21:30 -0600, Ignoramus14054
wrote:

Pete, what sort of a manual would you recommend, I can shell out some
$$$, not only to save money on repairs, but to learn something.

Repair manual or what is it called?

In the old days, they were called Factory Service Manuals. YMMV

--
....in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin

Larry Jaques wrote:
On Tue, 28 Feb 2012 21:25:33 -0600, Ignoramus14054
wrote:


snip

Larry, what sort of manual would you suggest?

The Chevrolet Truck service manual, Ig. Maybe eBay?
http://www.ebay.com/sch/i.html?_nkw=...+repair+manual

The dealership are way too damned proud of their manuals, wanting
several hundred dollars for them.

Second choice would be a Mitchell manual for the truck. We used them
for all repair work when I was a mechanic at non-dealer sites. They're
great! (Not cheap.) Try this link. (unknown to me)
http://www.mitchell1.com/M1Products/...uck/index.html

There's apparently some service recall on diesel injectors.
http://tinyurl.com/7xw8s9e



I downloaded one from here last week: http://www.downloadamanual.net/

I was dubious about the site but all went well, $20 for what looks like the
full factory manual set. Their search function is ****e, it took me a while
to find what I wanted.


G'luck!

On Tue, 28 Feb 2012 21:07:33 -0600, "Pete C."
wrote:


Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.


You say 2 volts and 4 volts.
This does not compute. WITH THE INJECTORS DISCONNECTED what voltage
do you have on one side of the injector with the key turned on?
It SHOULD be roughly 12 volts from terminal to ground. When the
computer triggers the injector, the computer GROUNDS the injector for
a short time. Measuring across the injector will give you a low
voltage that varies with fuel requirement.
A bad ground on the computer will cause a low voltage drop across the
injector which translates to low injector current and reduced injector
opening. The same will happen with high resistance in the power supply
circuit.
The voltage on the "feed " side of the injector should remain at 12
volts even when cranking (well, it WILL drop some - but it should
remain "battery voltage"). If it drops below battery cranking vultage
you have a bad connection somewhere in the power feed circuit.

To test the fuel pressure regulator pinch the rubber return line and
see what happens to the pressure. Those regulators have a bad
reputation, for a good reason. Note - the RETURN line, not the feed or
the vacuum signal line. The injection pressure is regulated to
provide the same pressure drop across the injector under WOT (low vac,
or high manifold absolute pressure) as under low throttle (high vac,
or low manifold absolute pressure) so a given period of injector
opening provides the same amount of fuel regardless of engine fuel
demand.

In article ,
Larry Jaques wrote:

On Tue, 28 Feb 2012 21:25:33 -0600, Ignoramus14054
wrote:

On 2012-02-29, Larry Jaques wrote:
On Tue, 28 Feb 2012 19:29:17 -0600, Ignoramus14054
wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

Yes, that's possible. But electronic ignition systems and EFI are
computer controlled. Unless they get all their ducks in a row, things
don't work properly. Get the manual, get the test equipment and let
us know what you find. Or have a tech drop by with same and let you
know.


Larry, what sort of manual would you suggest?

The Chevrolet Truck service manual, Ig. Maybe eBay?
http://www.ebay.com/sch/i.html?_nkw=...+repair+manual

The dealership are way too damned proud of their manuals, wanting
several hundred dollars for them.

Second choice would be a Mitchell manual for the truck. We used them
for all repair work when I was a mechanic at non-dealer sites. They're
great! (Not cheap.) Try this link. (unknown to me)
http://www.mitchell1.com/M1Products/...uck/index.html



Also take a look here for the manual/s:

http://www.faxonautoliterature.com/

IIRC, depending on vehicle, they have original factory shop manuals
(FSM), reproduced FSM's and the ones like the DIY parts stores carry.
For some vehicles they even carry factory assembly, parts and owners
manuals.

I've only had one personal experience with them and it was positive.
Have some friends who speak highly of them too.

As the above poster mentioned, Mitchell manuals rock too.

And a question: is fuel leaking 'through' and dripping off your
injector/s, or somewhere else and just running down and off your
injector/s

In a nutshell, remember most (if not all) injectors are energized on one
lead anytime the key is on, and controlled via the ground side through
the computer. Needless to say, a good computers ground is very important.

Erik






There's apparently some service recall on diesel injectors.
http://tinyurl.com/7xw8s9e

G'luck!

--
...in order that a man may be happy, it is
necessary that he should not only be capable
of his work, but a good judge of his work.
-- John Ruskin

On 2/28/2012 10:14 PM, Larry Jaques wrote:
....

There's apparently some service recall on diesel injectors.
http://tinyurl.com/7xw8s9e
....

No bearing on TBI system on a gas engine, though...

--

Ignoramus14054 wrote:

On 2012-02-29, Pete C. wrote:

Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.

Pete, what sort of a manual would you recommend, I can shell out some
$$$, not only to save money on repairs, but to learn something.

Repair manual or what is it called?

i

If it's close enough to be of use, I could send you my old 1990 R,V,P,G
series service manual. It's far too big to scan all of it, but it would
fit in a PMFRB ok.

Jon Elson wrote:

Ignoramus14054 wrote:

1) Lack of fuel pressure
Possibly the wrong fuel pump. I would expect this TBI needs
something close to 50 PSI at the minimum.
2) Lack of voltage supplied to the TBI.


Maybe not. The computer probably sends short pulse-width
modulated pulses of 12 V to the injectors. If the starter
isn't too noisy, you should be able to hear it clicking
when you crank. You can definitely hear the injectors on
most injection systems (but maybe not with the starter
running).

You can get NOID lights on loan from many auto parts places (with
deposit), and the injectors are usually driven on the low side.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Maybe, should be relatively easy to check. Yes, could be a bad
ground. The fuel pump is probably not controlled by much electronics.
There may be a fuel pump cutoff relay, but that usually is on
cars with airbags.

Two sources of power to the fuel pump, one if the fuel pump relay
controlled by the PCM and the second is an oil pressure switch.

But, I'd measure the fuel pump pressure.
Somewhere there ought to be a spec on fuel pump pressure. A
quick test just with a gauge connected to the pump would tell you
whether you are getting 10 PSI (carb pump) or 50 PSI (FI pump).

According to the doc, the old TBI systems are supposed to run 9-13 PSI,
quite a bit less than the later MPFI systems. A FI pressure tester is
about $20 at the auto parts place.


The injectors may be working perfectly, but with no fuel pressure,
the computer is applying short pulses that SHOULD be right at
the higher pressure.

Also, since the pressure regulator made a difference, it may show
that the regulator has a ripped diphragm, crud under the seat or
some other malfunction. Actually, a typical regulator would
set lower pressure without the spring. But, this one might not
be typical.

Jon

On 2012-02-29, Pete C. wrote:

Jon Elson wrote:

Ignoramus14054 wrote:

1) Lack of fuel pressure
Possibly the wrong fuel pump. I would expect this TBI needs
something close to 50 PSI at the minimum.
2) Lack of voltage supplied to the TBI.


Maybe not. The computer probably sends short pulse-width
modulated pulses of 12 V to the injectors. If the starter
isn't too noisy, you should be able to hear it clicking
when you crank. You can definitely hear the injectors on
most injection systems (but maybe not with the starter
running).

You can get NOID lights on loan from many auto parts places (with
deposit), and the injectors are usually driven on the low side.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Maybe, should be relatively easy to check. Yes, could be a bad
ground. The fuel pump is probably not controlled by much electronics.
There may be a fuel pump cutoff relay, but that usually is on
cars with airbags.

Two sources of power to the fuel pump, one if the fuel pump relay
controlled by the PCM and the second is an oil pressure switch.

But, I'd measure the fuel pump pressure.
Somewhere there ought to be a spec on fuel pump pressure. A
quick test just with a gauge connected to the pump would tell you
whether you are getting 10 PSI (carb pump) or 50 PSI (FI pump).

According to the doc, the old TBI systems are supposed to run 9-13 PSI,
quite a bit less than the later MPFI systems. A FI pressure tester is
about $20 at the auto parts place.

Where do they plug in?


The injectors may be working perfectly, but with no fuel pressure,
the computer is applying short pulses that SHOULD be right at
the higher pressure.

Also, since the pressure regulator made a difference, it may show
that the regulator has a ripped diphragm, crud under the seat or
some other malfunction. Actually, a typical regulator would
set lower pressure without the spring. But, this one might not
be typical.

Jon

On 2012-02-29, wrote:
On Tue, 28 Feb 2012 21:07:33 -0600, "Pete C."
wrote:


Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.


You say 2 volts and 4 volts.
This does not compute. WITH THE INJECTORS DISCONNECTED what voltage
do you have on one side of the injector with the key turned on?

I was measuring voltage between two terminals going to the injector
body, with an averaging voltmeter.

It SHOULD be roughly 12 volts from terminal to ground. When the
computer triggers the injector, the computer GROUNDS the injector for
a short time. Measuring across the injector will give you a low
voltage that varies with fuel requirement.

Right.

A bad ground on the computer will cause a low voltage drop across the
injector which translates to low injector current and reduced injector
opening. The same will happen with high resistance in the power supply
circuit.

Which is what a bad ground is, kind of .

The voltage on the "feed " side of the injector should remain at 12
volts even when cranking (well, it WILL drop some - but it should
remain "battery voltage"). If it drops below battery cranking vultage
you have a bad connection somewhere in the power feed circuit.

Sounds like a good thing to check, voltage on the feed side
vs. ground/body potential.

To test the fuel pressure regulator pinch the rubber return line and
see what happens to the pressure.

Another great idea, will try to find it.

Those regulators have a bad reputation, for a good reason. Note -
the RETURN line, not the feed or the vacuum signal line.

That vacuum line, I think, is disconnected, may be an issue.

The
injection pressure is regulated to provide the same pressure drop
across the injector under WOT (low vac, or high manifold absolute
pressure) as under low throttle (high vac, or low manifold absolute
pressure) so a given period of injector opening provides the same
amount of fuel regardless of engine fuel demand.

OK, why do the regulators have a bad reputation?

Thanks a lot

i

On Tue, 28 Feb 2012 21:14:57 -0600, Jon Elson
wrote:

Ignoramus14054 wrote:


1) Lack of fuel pressure
Possibly the wrong fuel pump. I would expect this TBI needs
something close to 50 PSI at the minimum.
2) Lack of voltage supplied to the TBI.

Maybe not. The computer probably sends short pulse-width
modulated pulses of 12 V to the injectors. If the starter
isn't too noisy, you should be able to hear it clicking
when you crank. You can definitely hear the injectors on
most injection systems (but maybe not with the starter
running).
I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).
Maybe, should be relatively easy to check. Yes, could be a bad
ground. The fuel pump is probably not controlled by much electronics.
There may be a fuel pump cutoff relay, but that usually is on
cars with airbags. But, I'd measure the fuel pump pressure.
Somewhere there ought to be a spec on fuel pump pressure. A
quick test just with a gauge connected to the pump would tell you
whether you are getting 10 PSI (carb pump) or 50 PSI (FI pump).

The injectors may be working perfectly, but with no fuel pressure,
the computer is applying short pulses that SHOULD be right at
the higher pressure.

Also, since the pressure regulator made a difference, it may show
that the regulator has a ripped diphragm, crud under the seat or
some other malfunction. Actually, a typical regulator would
set lower pressure without the spring. But, this one might not
be typical.

Jon
It will be a very typical regulator - and no spring WILL make no
pressure. I've rebuilt and modified those regulators to make them
adjustable - friend's 350 TBI engine was running lean due to a
combination of lower than spec pressure and a modified Throttle Body.
The regulators are, as I said before, notorious for being in-accurate.
General spec is between 9 and 13 psi. This one was running at about 8
and dribbled. We set it to 15 and got a real good atomized spray
pattern, the fuel consumption dropped, power improved, and the truck
didn't run hot any more.

If he followed my instructions in my last post he'll KNOW where the
problem is NOT, even if it doesn't pin down exactly what the problem
is.

I've worked on this stuff a lot over the years - back when that thing
was current, but not so much today.

On Wed, 29 Feb 2012 11:22:21 -0600, Ignoramus1127
wrote:

On 2012-02-29, wrote:
On Tue, 28 Feb 2012 21:07:33 -0600, "Pete C."
wrote:


Ignoramus14054 wrote:


"Ignoramus10095" wrote in message
I have a Chevy Kodiak dump truck that I am trying to fix.
Pictures of the truck and carburetor are he
http://igor.chudov.com/tmp/Chevy-Kodiak/
Onboard computer bad ?
Check fuel line pressure ?

Looks like throttle body injection (TBI), lots of stuff to go wrong.


Tom, and others, I took some time off this problem, and also took some
time to work on it and diagnose it properly.

Yes, this is based on TBI (throttle body injection).

We replaced the fuel pump, at least some fuel filters, and injector
bodies.

It did not help. Even with new injector bodies, the fuel would, at
best, drip from the injectors. drip, drip, drip

Then I decided to NOT take shortcuts and diagnose things properly,
using proper troubleshooting techniques, organize my workplace etc.

As you know, before the injector bodies, there is a pressure
regulator. It has a spring inside. For testing purposes, I removed the
spring, essentially disabling pressure regulation.

We cranked the engine again, again to the same result. Dripping, not
enough fuel.

Then I measured the voltage supplied to injector bodies, it sort of
varied, but would hover around 2 volts. It seemed low.

Then, I took out the wires coming from the engine, plugged in my
little alligator clips, and supplied 4 volts to the injector body,
using my DC power supply.

Voila, the fuel came out in some force (but not as a shower), the
engine would start and run fine.

I put the regulator back in and, guess what, no fuel again,
even with 4 volts applied to injector bodies.

I ended my experiment right there and went home to think.

Clearly, without the pressure regulator (at full supplied fuel line
pressure), and with more volts supplied to injector bodies, the engine
runs. But what des it mean?

My current thinking is that I seemingly have two problems

1) Lack of fuel pressure
2) Lack of voltage supplied to the TBI.

I have a feeling that both items are a manifestation of the same
problem, which is lack of voltage in the fuel subsystem. I think that
both the fuel pump is not getting enough volts (so not enough fuel
pressure), and also, the injectors are not getting enough volts (so
they do not open properly).

Makes sense?

If so, what could it be? Bad ground?

i

Bad grounds could certainly do it. The pressure regulator may be ok, but
the fuel pump may have a low voltage condition as well and not be
keeping up the appropriate flow.


You say 2 volts and 4 volts.
This does not compute. WITH THE INJECTORS DISCONNECTED what voltage
do you have on one side of the injector with the key turned on?

I was measuring voltage between two terminals going to the injector
body, with an averaging voltmeter.

It SHOULD be roughly 12 volts from terminal to ground. When the
computer triggers the injector, the computer GROUNDS the injector for
a short time. Measuring across the injector will give you a low
voltage that varies with fuel requirement.

Right.

A bad ground on the computer will cause a low voltage drop across the
injector which translates to low injector current and reduced injector
opening. The same will happen with high resistance in the power supply
circuit.

Which is what a bad ground is, kind of .
Not at all. The ground is in the CONTROL circuit.

The voltage on the "feed " side of the injector should remain at 12
volts even when cranking (well, it WILL drop some - but it should
remain "battery voltage"). If it drops below battery cranking vultage
you have a bad connection somewhere in the power feed circuit.

Sounds like a good thing to check, voltage on the feed side
vs. ground/body potential.

To test the fuel pressure regulator pinch the rubber return line and
see what happens to the pressure.

Another great idea, will try to find it.

Those regulators have a bad reputation, for a good reason. Note -
the RETURN line, not the feed or the vacuum signal line.

That vacuum line, I think, is disconnected, may be an issue.

The
injection pressure is regulated to provide the same pressure drop
across the injector under WOT (low vac, or high manifold absolute
pressure) as under low throttle (high vac, or low manifold absolute
pressure) so a given period of injector opening provides the same
amount of fuel regardless of engine fuel demand.

OK, why do the regulators have a bad reputation?

Thanks a lot

i

A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

i

On Fri, 02 Mar 2012 11:20:52 -0600, Ignoramus22470
wrote:

A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

Terrific for fuel economy!


The truck now runs great and I have a foot in my mouth.

i

That makes it hard to work the clutch and the throttle at the same
time.

--
Ed Huntress

On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--

"Ignoramus22470" wrote in
message ...
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so
the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

i

Slava Bogy for easy fixes.

On 2012-03-02, dpb wrote:
On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--


The original problem was bad fuel pump in the tank.

I got the tank separated from the truck and hooked it up wrong. The
lines, unfortunately, were interchangeable.

i

i

On Fri, 02 Mar 2012 13:05:17 -0600, Ignoramus22470
wrote:

On 2012-03-02, dpb wrote:
On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--


The original problem was bad fuel pump in the tank.

I got the tank separated from the truck and hooked it up wrong. The
lines, unfortunately, were interchangeable.

Oops. There is something to be said for keeping a roll of tape and a
Sharpie handy, and tagging things as they come apart so you can make
sure they go back together the same way.

And/or take a few pictures before you start, and a few more as you go,
of how it went together. (Sometimes you have to make an un-planned
stop for a day or two, and totally forget.)

And/or grab a paint marker and permanently mark "Vent" and "Supply"
and "Return" on the steel lines once you figure out which is which -
then you can check that against the markings on the pump when it's
going back together.

I still do silly things that, even when it's a job I've done hundreds
of times. 99% of the time it goes back together easy, but there's
always the one time in a hundred it doesn't...

Oh, and as you put it back together you put the date on those hoses
and clamps and on the fuel pump itself a White Paint Marker is perfect
for that. You just replaced the hoses in 2012, no sense in forgetting
when you did them last and trying to change them again till at least
2020. Some of those high-pressure fuel hoses are $10 plus a foot.

Date and Mileage on the Oil Filter canister too.

-- Bruce --

On 2012-03-02, Bruce L. Bergman (munged human readable) wrote:
On Fri, 02 Mar 2012 13:05:17 -0600, Ignoramus22470
wrote:

On 2012-03-02, dpb wrote:
On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--


The original problem was bad fuel pump in the tank.

I got the tank separated from the truck and hooked it up wrong. The
lines, unfortunately, were interchangeable.

Oops. There is something to be said for keeping a roll of tape and a
Sharpie handy, and tagging things as they come apart so you can make
sure they go back together the same way.

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.

i


And/or take a few pictures before you start, and a few more as you go,
of how it went together. (Sometimes you have to make an un-planned
stop for a day or two, and totally forget.)

And/or grab a paint marker and permanently mark "Vent" and "Supply"
and "Return" on the steel lines once you figure out which is which -
then you can check that against the markings on the pump when it's
going back together.

I still do silly things that, even when it's a job I've done hundreds
of times. 99% of the time it goes back together easy, but there's
always the one time in a hundred it doesn't...

Oh, and as you put it back together you put the date on those hoses
and clamps and on the fuel pump itself a White Paint Marker is perfect
for that. You just replaced the hoses in 2012, no sense in forgetting
when you did them last and trying to change them again till at least
2020. Some of those high-pressure fuel hoses are $10 plus a foot.

Date and Mileage on the Oil Filter canister too.

-- Bruce --

On Fri, 02 Mar 2012 11:20:52 -0600, Ignoramus22470
wrote:

A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

i
I hope you at least trimmed your toe-nails first!!!

On Fri, 02 Mar 2012 13:05:17 -0600, Ignoramus22470
wrote:

On 2012-03-02, dpb wrote:
On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--


The original problem was bad fuel pump in the tank.

I got the tank separated from the truck and hooked it up wrong. The
lines, unfortunately, were interchangeable.

i

i
So they were reversed AT THE PUMP. I can see that happening if it came
to you in pieces and you were not familiar with the system - - - -.

On 2012-03-03, wrote:
On Fri, 02 Mar 2012 13:05:17 -0600, Ignoramus22470
wrote:

On 2012-03-02, dpb wrote:
On 3/2/2012 11:20 AM, Ignoramus22470 wrote:
A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

So just out of curiosity what was the original fundamental problem
(presuming you didn't receive the truck w/ the lines reversed)?

I'm at least somewhat surprised could do that--on the GM trucks I have
here the lines aren't interchangeable--the feed line is larger than
return, typically.

--


The original problem was bad fuel pump in the tank.

I got the tank separated from the truck and hooked it up wrong. The
lines, unfortunately, were interchangeable.

i

i
So they were reversed AT THE PUMP. I can see that happening if it came
to you in pieces and you were not familiar with the system - - - -.


Exactly. Came in pieces, I was not familiar.

i

On Fri, 02 Mar 2012 14:42:27 -0600, Ignoramus22470
wrote:

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.

Oh, missed that part - and it's totally understandable.

That's one of the things that GM usually does, they make the hoses a
different size so they can't go together backwards.

Which is maddening because you think you've got a roll of the right
hose before you started the job, then you need to stop work and go run
off to the Auto Parts and get the other size hose...

On 3/3/2012 1:50 PM, Bruce L. Bergman (munged human readable) wrote:
On Fri, 02 Mar 2012 14:42:27 -0600, Ignoramus22470
wrote:

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.

Oh, missed that part - and it's totally understandable.

That's one of the things that GM usually does, they make the hoses a
different size so they can't go together backwards.
....

Indeed which is why I still find it at least a little puzzling it was
doable. But, I've not had a Kodiak version of the Chebby; only the C60
(which is seriously old as in antique) and the C70 is only about 15 yr
newer. Since then we've gone to the tractor/trailer route for actual
hauling, 4-500 bu that seemed big load way back when just won't cut it
now when it's a 2 hr or longer wait-time to unload .

--

On 2012-03-03, dpb wrote:
On 3/3/2012 1:50 PM, Bruce L. Bergman (munged human readable) wrote:
On Fri, 02 Mar 2012 14:42:27 -0600, Ignoramus22470
wrote:

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.

Oh, missed that part - and it's totally understandable.

That's one of the things that GM usually does, they make the hoses a
different size so they can't go together backwards.
...

Indeed which is why I still find it at least a little puzzling it was
doable. But, I've not had a Kodiak version of the Chebby; only the C60
(which is seriously old as in antique) and the C70 is only about 15 yr
newer. Since then we've gone to the tractor/trailer route for actual
hauling, 4-500 bu that seemed big load way back when just won't cut it
now when it's a 2 hr or longer wait-time to unload .

--

Well, all lines were interchangeable, size wise. Not all could reach
to all nipples, but some could (and were) mixed up.

I have decided that until I find a cheap enough and suitable enough
semi trailer for my semi tractor, I will use the dump truck and the
15k trailer that I have, for moving industrial surplus stuff around.

i
i

Ignoramus22470 wrote:

A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

Oh, GOSH! Well, when working with unfamiliar equipment with
multiple hoses, it is easy to have something like this happen.
That would certainly foul up the regulator function and explain
why the spring worked opposite of how it should. Take the
foot out, you DID find and fix the problem, it just took a little
bit longer!

Jon

Ignoramus20398 wrote:



I have decided that until I find a cheap enough and suitable enough
semi trailer for my semi tractor, I will use the dump truck and the
15k trailer that I have, for moving industrial surplus stuff around.
Oh MY! Be REALLY careful which handle you grab, or a big lathe could get
dumped in the middle of the street!

Jon

On 2012-03-04, Jon Elson wrote:
Ignoramus22470 wrote:

A followup. Very embarrassing and very typical.

What was wrong was that I mixed up the supply and return lines, so the
fuel pump was pumping into the return line.

The truck now runs great and I have a foot in my mouth.

Oh, GOSH! Well, when working with unfamiliar equipment with
multiple hoses, it is easy to have something like this happen.
That would certainly foul up the regulator function and explain
why the spring worked opposite of how it should. Take the
foot out, you DID find and fix the problem, it just took a little
bit longer!

Jon

Yes, the excuse I had is that I have never seen it connected
correctly, and the lines are compatible even with wrong nipples.

Thanks

i

On 2012-03-04, Jon Elson wrote:
Ignoramus20398 wrote:



I have decided that until I find a cheap enough and suitable enough
semi trailer for my semi tractor, I will use the dump truck and the
15k trailer that I have, for moving industrial surplus stuff around.
Oh MY! Be REALLY careful which handle you grab, or a big lathe could get
dumped in the middle of the street!

Jon

\A scary thought. As a matter of fact, I believe that I cannot operate
the dump unless I am in neutral.

i

Ignoramus20398 wrote:
On 2012-03-03, dpb wrote:
On 3/3/2012 1:50 PM, Bruce L. Bergman (munged human readable) wrote:
On Fri, 02 Mar 2012 14:42:27 -0600, Ignoramus22470
wrote:

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.
Oh, missed that part - and it's totally understandable.

That's one of the things that GM usually does, they make the hoses a
different size so they can't go together backwards.
...

Indeed which is why I still find it at least a little puzzling it was
doable. But, I've not had a Kodiak version of the Chebby; only the C60
(which is seriously old as in antique) and the C70 is only about 15 yr
newer. Since then we've gone to the tractor/trailer route for actual
hauling, 4-500 bu that seemed big load way back when just won't cut it
now when it's a 2 hr or longer wait-time to unload .

--

Well, all lines were interchangeable, size wise. Not all could reach
to all nipples, but some could (and were) mixed up.

I have decided that until I find a cheap enough and suitable enough
semi trailer for my semi tractor, I will use the dump truck and the
15k trailer that I have, for moving industrial surplus stuff around.

i
i


Got your CDL yet? If not I wouldn't be driving that dump around.

--
Steve W.

On 2012-03-04, Steve W. wrote:
Ignoramus20398 wrote:
On 2012-03-03, dpb wrote:
On 3/3/2012 1:50 PM, Bruce L. Bergman (munged human readable) wrote:
On Fri, 02 Mar 2012 14:42:27 -0600, Ignoramus22470
wrote:

I received them apart, I never had them assembled correctly.

The tank was on the shelves and the truck was in the yard.
Oh, missed that part - and it's totally understandable.

That's one of the things that GM usually does, they make the hoses a
different size so they can't go together backwards.
...

Indeed which is why I still find it at least a little puzzling it was
doable. But, I've not had a Kodiak version of the Chebby; only the C60
(which is seriously old as in antique) and the C70 is only about 15 yr
newer. Since then we've gone to the tractor/trailer route for actual
hauling, 4-500 bu that seemed big load way back when just won't cut it
now when it's a 2 hr or longer wait-time to unload .

--

Well, all lines were interchangeable, size wise. Not all could reach
to all nipples, but some could (and were) mixed up.

I have decided that until I find a cheap enough and suitable enough
semi trailer for my semi tractor, I will use the dump truck and the
15k trailer that I have, for moving industrial surplus stuff around.

i
i


Got your CDL yet? If not I wouldn't be driving that dump around.


Yep. Studying hard right now.

i

On 3/3/2012 11:10 PM, Ignoramus20398 wrote:
....

\A scary thought. As a matter of fact, I believe that I cannot operate
the dump unless I am in neutral.

That's _very_ unlikely; any dump would want to be able to spread a load
of gravel, for example.

You'll have to clutch to engage the PTO, but when you let it out, it
won't care which gear the tranny is in...

--

On 3/4/2012 9:13 AM, dpb wrote:
On 3/3/2012 11:10 PM, Ignoramus20398 wrote:
...

\A scary thought. As a matter of fact, I believe that I cannot operate
the dump unless I am in neutral.

That's _very_ unlikely; any dump would want to be able to spread a load
of gravel, for example.

You'll have to clutch to engage the PTO, but when you let it out, it
won't care which gear the tranny is in...

There's a second hydraulic valve control as well that will have to be
closed(/opened depending on your point of view ) to cause the bed to
raise as well...so you won't be raising it by pure chance on the
interstate.

While we're telling stories, I'll relate one I did as a HS kid working
for local ready-mix guy one summer it was too hot/dry so had no field
work at home on the farm. Hauling dirt from foundation/floor slab prep
work on the new hospital wing here to a fill location on south side of
town. I'd made a bunch of trips that day, was getting late and was
tired and ready to go do something more exciting for the evening when I
forgot to pull the tailgate lever before raising the bed on one load.
All of a sudden, I'm looking at a about a 45 degree angle up to the
north as the truck body returns to the "fully upright and locked
position" w/ the load still on.

A little startled from my daydreams, I considered there really was no
alternative but to try the lever (which, fortunately, was one of those
mounted on the front of the bed by the driver's door so could do from
the cab w/o getting out of the truck. If it hadn't been, would have
been a trick to get there as it was quite a ways down to the ground at
that point ). So, I pull and WHAM! the front wheels hit the ground,
the engine dies and I bounce around in the cab pretty good. Get out,
look around, see no blown tires or oil on the ground so climb in crank
up and go on. No harm, no foul... I did learn not to do _that_
again, though. I was probably 16 that year if my years aren't too
mixed up; think that would have been after my sophomore year in HS.

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