I'm having very intermittent lack of starter rotation on a Toyota
T-100. Over the last 14 years I have replaced the contacts it the
solenoid and more recently (1 to 2 years) replaced the starter.
For trouble shooting I have a meter with one lead connected to the
bolt on the solenoid and the other to the frame.
The plan is; if I can get it to malfunction while trying to start it
and the voltage on the solenoid is 13.7v vs 10.7 then I know the
solenoid contacts didn't connect (if they clicked) or the starter is
open (less likely).
If the solenoid clicks and the voltage drops to a low value then I
probably have a bad connection in the wiring.

So far I have engaged the starter 25 times without malfunction.
Letting things cool, then I'll try again, if I hit 100 my work is done
for this go round!

Question 1) The battery voltage sets at 12.7, when I energize the
starter it drops to 10.7.
Is that a normal voltage under starter load?

Question 2) In the old days, you could remove the coil wire to run a
starter without starting the motor.
How do you disable the spark on these newer vehicles without a
distributor cap? (newer 1997) :-)

Mikek

On 9/25/2014 10:39 AM, amdx wrote:


I'm having very intermittent lack of starter rotation on a Toyota
T-100. Over the last 14 years I have replaced the contacts in the
solenoid and more recently (1 to 2 years) replaced the starter.
For trouble shooting I have a meter with one lead connected to the
bolt on the solenoid and the other to the frame. (solenoid is built in the starter)

The plan is; if I can get it to malfunction while trying to start it
and the voltage on the solenoid is 12.7v vs 10.7 then I know the
solenoid contacts didn't connect (if they clicked) or the starter is
open (less likely).
If the solenoid clicks and the voltage drops to a low value then I
probably have a bad connection in the wiring.

So far I have engaged the starter 25 times without malfunction.
Letting things cool, then I'll try again, if I hit 100 my work is done
for this go round!

Mikek



Ok, after about ten more times switching the key to start, the
starter did NOT engage. and the voltage stayed at 11.9v VS 10.7v
when the starter engaged.

So by my logic I suspect the contacts in the solenoid.

Anyone have other thoughts and a way to differentiate.
Oh, I like that going for a differential diagnoses!

Mikek

PS. I lament selling my Simpson 260, I had to grab a panel meter and
adjust it from a 75 volt meter to a 15 volt meter. Digital meters are
not real helpful for this type of testing.

"amdx" wrote in message
...
On 9/25/2014 10:39 AM, amdx wrote:


I'm having very intermittent lack of starter rotation on a Toyota
T-100. Over the last 14 years I have replaced the contacts in the
solenoid and more recently (1 to 2 years) replaced the starter.
For trouble shooting I have a meter with one lead connected to the
bolt on the solenoid and the other to the frame. (solenoid is built in
the starter)

The plan is; if I can get it to malfunction while trying to start it
and the voltage on the solenoid is 12.7v vs 10.7 then I know the
solenoid contacts didn't connect (if they clicked) or the starter is
open (less likely).
If the solenoid clicks and the voltage drops to a low value then I
probably have a bad connection in the wiring.

So far I have engaged the starter 25 times without malfunction.
Letting things cool, then I'll try again, if I hit 100 my work is done
for this go round!

Mikek



Ok, after about ten more times switching the key to start, the starter
did NOT engage. and the voltage stayed at 11.9v VS 10.7v
when the starter engaged.

So by my logic I suspect the contacts in the solenoid.

Anyone have other thoughts and a way to differentiate.
Oh, I like that going for a differential diagnoses!

Mikek

PS. I lament selling my Simpson 260, I had to grab a panel meter and
adjust it from a 75 volt meter to a 15 volt meter. Digital meters are
not real helpful for this type of testing.

Is the replacement starter a new one or a rebuild?

In article , amdx wrote:

I'm having very intermittent lack of starter rotation on a Toyota
T-100. Over the last 14 years I have replaced the contacts it the
solenoid and more recently (1 to 2 years) replaced the starter.

For what it's worth, I had repeated problems with the starter on a
Ford Aerostar I owned - I believe the engine and starter were of
Mitsubishi origin.

The symptoms were that every three years or so, cranking would become
intermittent - occasionally slow to start cranking. It would get
worse and worse, and eventually the starter would fail to engage at
all. Sometimes, if the starter wouldn't work after the vehicle had
been stopped only for a short time, I could let the vehicle sit for a
couple of hours and it would start again.

I had to have the starter replaced two or three times during the time
I owned the Aerostar. It would always fix the problem... for about
three years... and then it would recur.

What I was told, by one of the mechanics who worked on it, was that
the starter was prone to developing a bad spot on the
commutator... I'd guess it was due to arcing. If the bad spot was
bad/burned enough, then when the starter happened to stop rotating
with this spot under one of the brushes, there wouldn't be adequate
contact and the starter would not crank.

It would probably have been possible to service the starter (open it
up and re-turn the commutator ring) and I imagine that's probably what
was done to the "remanufactured" starters I bought.

On 9/25/2014 11:23 AM, Tom Miller wrote:

"amdx" wrote in message
...
On 9/25/2014 10:39 AM, amdx wrote:


I'm having very intermittent lack of starter rotation on a Toyota
T-100. Over the last 14 years I have replaced the contacts in the
solenoid and more recently (1 to 2 years) replaced the starter.
For trouble shooting I have a meter with one lead connected to the
bolt on the solenoid and the other to the frame. (solenoid is built
in the starter)

The plan is; if I can get it to malfunction while trying to start it
and the voltage on the solenoid is 12.7v vs 10.7 then I know the
solenoid contacts didn't connect (if they clicked) or the starter is
open (less likely).
If the solenoid clicks and the voltage drops to a low value then I
probably have a bad connection in the wiring.

So far I have engaged the starter 25 times without malfunction.
Letting things cool, then I'll try again, if I hit 100 my work is done
for this go round!

Mikek



Ok, after about ten more times switching the key to start, the
starter did NOT engage. and the voltage stayed at 11.9v VS 10.7v
when the starter engaged.

So by my logic I suspect the contacts in the solenoid.

Anyone have other thoughts and a way to differentiate.
Oh, I like that going for a differential diagnoses!

Mikek

PS. I lament selling my Simpson 260, I had to grab a panel meter and
adjust it from a 75 volt meter to a 15 volt meter. Digital meters are
not real helpful for this type of testing.

Is the replacement starter a new one or a rebuild?


I didn't put it on, my had here nephew put it on, and he usually gets
parts at Napa. However my wife gave me orders to get new contacts at
Toyota, so I figured she must have talked to him (she wouldn't now such
a thing to say) That makes me think maybe he got it at Toyota.
The receipt is in 2012 0r 2013 file, but I don't care to dig it out.

But I don't want to throw parts at it, rather figure it out first.
I have notice oil on the starter/solenoid, it is dripping from the
valve cover, I tighten the screws, they were all very loose.
So, a new theory, oil has contaminated the contacts making for
intermittent starting. I'm holding off until the problem clears or
becomes more consistent.
Mikek

On Thu, 25 Sep 2014 10:54:14 -0500, amdx wrote:

Ok, after about ten more times switching the key to start, the
starter did NOT engage. and the voltage stayed at 11.9v VS 10.7v
when the starter engaged.

So by my logic I suspect the contacts in the solenoid.

Remember that another set of "contacts" involved are the contacts the
brushes make to the commutator....

Jonesy
--
Marvin L Jones | Marvin | W3DHJ | linux
38.238N 104.547W | @ jonz.net | Jonesy | OS/2
* Killfiling google & XXXXbanter.com: jonz.net/ng.htm

amdx wrote:
Question 1) The battery voltage sets at 12.7, when I energize the
starter it drops to 10.7.
Is that a normal voltage under starter load?

Yeah. The starter can be drawing up to a couple of hundred amps, so
it's normal for it to go down some. I have heard various values for
the line between "good" and "bad", usually somewhere between 9 and
10 V.

Question 2) In the old days, you could remove the coil wire to run a
starter without starting the motor.
How do you disable the spark on these newer vehicles without a
distributor cap? (newer 1997) :-)

Probably the most common is to remove the fuel pump relay or fuse, or
unplug the fuel pump. Note that if the vehicle has been run recently,
there might still be enough pressure in the injection system to run the
engine for several seconds the first time you crank it after removing
the fuse/relay or unplugging.

If you have the style where multiple coils sit on an ignition module,
unplugging the low-voltage connector to the ignition module will
usually kill the spark.

Matt Roberds