Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.


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On Tue, 05 Apr 2016 10:20:37 -0700, Snuffy \"Hub Cap\" McKinney wrote:

Any other suggestions? Thanks in advance.


Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

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On Tuesday, April 5, 2016 at 1:19:36 PM UTC-4, Snuffy "Hub Cap" McKinney wrote:
Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key.. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.


They will be (typically) some sort of little black box mounted on the firewall, or somewhere near the main fuse box or battery, it may look like a fancy connector as well. But it will be there. There will be no such thing on the ground side. Only on the + side.

Peter Wieck
Melrose Park, PA
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On Tue, 5 Apr 2016 10:20:37 -0700, "Snuffy \"Hub Cap\" McKinney"
wrote:

Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.

I just had a similar thing happen to my old Case backhoe. I turn the
key and the solenoid only clicks. Checking the voltage at the starter
when I try to start it the voltage dropped to about 2 volts. I
suspected that the starter motor had shorted out internally. I was
gonna pull it to test it and then my son gets down low so he can see
the bottom of the starter. He found that the heavy copper strip that
goes from the solenoid to the starter motor had been bent such that it
was touching the motor housing. So there was my short and it only
occurred when I attempted to start the backhoe. I figure a branch must
have somehow poked its way up far enough to hit the starter motor when
I was using the machine in the woods the other day.
Eric
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"Cursitor Doom" wrote in message ...
On Tue, 05 Apr 2016 10:20:37 -0700, Snuffy \"Hub Cap\" McKinney wrote:

Any other suggestions? Thanks in advance.


Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.


Posts are clean. New battery 2 months ago and cleaned good and check hot and neutral wires.



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wrote in message ...
On Tuesday, April 5, 2016 at 1:19:36 PM UTC-4, Snuffy "Hub Cap" McKinney wrote:
Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.


They will be (typically) some sort of little black box mounted on the firewall, or somewhere near the main fuse box or battery, it may look like a fancy connector as well. But it will be there. There will be no such thing on the ground side. Only on the + side.

Peter Wieck
Melrose Park, PA


Thanks, I looked and didn't see it yet. Hot battery terminal has one large and one small wire, both going directly to the solenoid relay mounted on the side wall. No voltage drop between battery post and relay connection.

3 others hot wired connected there on the same post go various places, but none go to anything that would have fuses, relays in it.

Will keep looking for it. I'm suspecting the problem is in the ground circuit. Will attack that next.



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wrote in message ...
On Tue, 5 Apr 2016 10:20:37 -0700, "Snuffy \"Hub Cap\" McKinney"
wrote:

Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.

I just had a similar thing happen to my old Case backhoe. I turn the
key and the solenoid only clicks. Checking the voltage at the starter
when I try to start it the voltage dropped to about 2 volts. I
suspected that the starter motor had shorted out internally. I was
gonna pull it to test it and then my son gets down low so he can see
the bottom of the starter. He found that the heavy copper strip that
goes from the solenoid to the starter motor had been bent such that it
was touching the motor housing. So there was my short and it only
occurred when I attempted to start the backhoe. I figure a branch must
have somehow poked its way up far enough to hit the starter motor when
I was using the machine in the woods the other day.
Eric


Thanks Eric. I'll check that here today. I replaced the solenoid & starter last week. Always careful with connections but as the wife says, I don't always notice everything....


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"Snuffy "Hub Cap" McKinney" wrote in message ...
Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.

===

Update from today....

I turned the key this morning and it started right up. When I got back home, I turned it off and on a few times and started each time without hesitation.

This morning the clock showed 5:30. When power is restored, the clock starts at 12:00. This means that the power was restored to the clock about the time I stopped troubleshooting yesterday. Last thing I did yesterday before locking it up was try to start it and all was dead, including panel, radio, lights, etc. Unless slamming the door jiggled a connection, I don't know what would have caused it. It would not be a heat-related problem because the engine was never started that day.

I don't want to go driving around town not knowing what the problem is but I'm stumped now.

So I guess what I'm looking for is some things to check the next time it won't start.

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Had something similar happen to a car. The battery was fine, the car wouldn't start. Turned out the battery cable had corroded below the battery where it didn't show - maybe got some acid drip from the battery? I dunno.

Anyway, the way we found it was checked voltage under load. There was plenty at the battery but not at the end of that wire.
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You need you wife or girlfriend or someone to turn the ignition key on and off while you check the voltage at the battery itself, and then going away from the battery to the chassis on the negative side and if ok those two places, go from chassis ground to the hot lead down the line from the battery toward the load. It must be either that the battery voltage drops under load, or that there is a high resistance somewhere in the circuit. You get to play Dick Tracy to find it.


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On Tue, 05 Apr 2016 13:48:45 -0700, hrhofmann wrote:

It must be either that the
battery voltage drops under load, or that there is a high resistance
somewhere in the circuit. You get to play Dick Tracy to find it.


Let's just hope for his sake it's not an intermittent fault (as it's
beginning to sound like) - they can make any fault 10x harder to find.

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In article , Snuffy-Hub-
says...

"Snuffy "Hub Cap" McKinney" wrote in message ...
Out of the blue, I turned the ignition key and the started jerked and stopped. Next turn solenoid clicked only. After that no sound on turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams show them but do not tell where to look for them. I assume close to the battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.

===

Update from today....

I turned the key this morning and it started right up. When I got back home, I turned it off and on a few times and started each time without hesitation.

This morning the clock showed 5:30. When power is restored, the clock starts at 12:00. This means that the power was restored to the clock about the time I stopped troubleshooting yesterday. Last thing I did yesterday before locking it up was try to start it and all was dead, including panel, radio, lights, etc. Unless slamming the door jiggled a connection, I don't know what would have caused it. It would not be a heat-related problem because the engine was never

started that day.

I don't want to go driving around town not knowing what the problem is but I'm stumped now.

So I guess what I'm looking for is some things to check the next time it won't start.


sure sounds like rusted body joints. Lots of cars depend on the body
being very connected for the ground. the Door slamming gives it away.


Jamie

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You didn't mention the make and model, that might help.

That the lights and radio were dead is telling. Some cars haqve the battery + going straight to the starter motor and the solenoid is mounted right there and also serves to engage the gear to the flywheel. It sound like that is where your bad connection is. Older GM cars were like that. Over the years the vibration can make that nut loosen up. Now that you got it to connect by jarring it (the door) and welded it together (by actually starting it, the connection might stay good for some time. However it is still unreliable and unreliable **** in cars is no good.

since you say you don't see any fusebox looking type of thing nearby, the connection point may well be right at the starter. I would crawl down there and undo it and redo it. Maybe brush up the connections a bit. I would say to test it by trying to turn them but they might be welded together so that test could easily yield a false negative. (no pun intended this time) If you redo those connections, remember to disconnect the negative battery cable first. When spark fly from something like that they can hurt your eyes, burn your clothes, and if there's ant gasoline laying around you might find out just how good your insurance is.
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On 6/04/2016 2:04 AM, Cursitor Doom wrote:
On Tue, 05 Apr 2016 10:20:37 -0700, Snuffy \"Hub Cap\" McKinney wrote:

Any other suggestions? Thanks in advance.


Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??


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"So when is grease on the terminals bad ??"

Before it is connected. After it is connected grease helps keep the elements away but you don't want it between the mating surfaces.
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"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??


When it gets between the battery post and the clamp.

If it is on the outside it is fine.


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On Tuesday, April 5, 2016 at 10:41:13 PM UTC-4, Ralph Mowery wrote:
"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??


When it gets between the battery post and the clamp.

If it is on the outside it is fine.


Conventional wisdom says when you tighten it down the grease gets squeezed out and there is direct metal to metal contact.

Whether that's based on data or not I don't know. But that's the way mechanics do it successfully.

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"Tim R" wrote in message
...
So when is grease on the terminals bad ??


When it gets between the battery post and the clamp.

If it is on the outside it is fine.


Conventional wisdom says when you tighten it down the grease gets squeezed
out and there is direct metal to metal contact.

Whether that's based on data or not I don't know. But that's the way
mechanics do it successfully.


Some mechanics can not be educated. If the grease is any good,not all of it
will be squeezed out so there is direct metal contact.

Think of it, the purpose of grease is to prevent metal to metal contact.

Clean the posts and clamps where they mate and put the clamps on. Then put
the grease or whatever you want on after that.



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"Ralph Mowery" wrote in message
...

"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what
it
sounds like to me.

So when is grease on the terminals bad ??


When it gets between the battery post and the clamp.


Most user/workshop manuals I've seen, advise a smear of petroleum jelly on
the battery posts to prevent a buildup of corrosion under the clamps.

Over the years, I've had various vehicles that seemed incapable of
containing their engine oil - once or twice the battery also got drenched,
apparently without any adverse effects.



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"Snuffy "Hub Cap" McKinney" wrote in
message ...
Out of the blue, I turned the ignition key and the started jerked and
stopped. Next turn solenoid clicked only. After that no sound on turning
key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully
charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams
show them but do not tell where to look for them. I assume close to the
battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.


Sounds like corrosion wherever the big earth cable from the battery gets
bolted to the chassis.

All the fuses are low current circuits (compared to the starter motor). A
common location for the fuse panel was on the bulkhead behind the engine -
nowadays more likely to be somewhere in or around the glove compartment.
Sometimes behind a removable panel beside the driver's footwell.

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On 04/06/2016 08:42 AM, Tim R wrote:
On Tuesday, April 5, 2016 at 10:41:13 PM UTC-4, Ralph Mowery wrote:
"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??


When it gets between the battery post and the clamp.

If it is on the outside it is fine.


Conventional wisdom says when you tighten it down the grease gets squeezed out and there is direct metal to metal contact.

Whether that's based on data or not I don't know. But that's the way mechanics do it successfully.


Of course air is a better insulator than grease.

The actual metal-to-metal contact area is surprisingly small--it's
roughly equal to the total preload divided by the yield strength of the
weaker material. As long as the grease can get out of the way of the
high spots that actually do the conducting, it won't hurt the conductance.

What it will do is keep acid out of the joint, which is a win.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net
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On Tue, 05 Apr 2016 17:51:18 -0500, amdx wrote:

Just to expound on the key off and on. If indeed the solenoid pulls
in, THEN is when you need to find the fault, current needs to flow to
find to find the bad connection. If you have 0.06 ohms of resistance in
a battery/starter circuit and the starter tries to draw 200 amps, there
is 12 volts dropped across your battery connection.*
You won't be able to measure 0.06 ohms.


At 200A, even one miliohm of connection resistance is going to waste 40W
of battery power.
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On Tue, 05 Apr 2016 17:51:18 -0500, amdx wrote:

Just to expound on the key off and on. If indeed the solenoid pulls
in, THEN is when you need to find the fault, current needs to flow to
find to find the bad connection. If you have 0.06 ohms of resistance in
a battery/starter circuit and the starter tries to draw 200 amps, there
is 12 volts dropped across your battery connection.*
You won't be able to measure 0.06 ohms.


Before and after cleaning all the connections in the starting circuit the voltage drop during starting is about the same - less than 3V.

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"Snuffy "Hub Cap" McKinney" wrote in message ...
On Tue, 05 Apr 2016 17:51:18 -0500, amdx wrote:

Just to expound on the key off and on. If indeed the solenoid pulls
in, THEN is when you need to find the fault, current needs to flow to
find to find the bad connection. If you have 0.06 ohms of resistance in
a battery/starter circuit and the starter tries to draw 200 amps, there
is 12 volts dropped across your battery connection.*
You won't be able to measure 0.06 ohms.


Before and after cleaning all the connections in the starting circuit the voltage drop during starting is about the same - less than 3V.

I meant to add that all the connections were tight but several had various levels of corrosion. After cleaning the overall resistance from pos or neg battery post to starter or block block went from around 1.9 to 1.4 ohms. That's not enough to prevent starting, but I suspect that one of the connections was intermittent.





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"Phil Hobbs" wrote in message ...
On 04/06/2016 08:42 AM, Tim R wrote:
On Tuesday, April 5, 2016 at 10:41:13 PM UTC-4, Ralph Mowery wrote:
"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??

When it gets between the battery post and the clamp.

If it is on the outside it is fine.


Conventional wisdom says when you tighten it down the grease gets squeezed out and there is direct metal to metal contact.

Whether that's based on data or not I don't know. But that's the way mechanics do it successfully.


Of course air is a better insulator than grease.

The actual metal-to-metal contact area is surprisingly small--it's
roughly equal to the total preload divided by the yield strength of the
weaker material. As long as the grease can get out of the way of the
high spots that actually do the conducting, it won't hurt the conductance.

What it will do is keep acid out of the joint, which is a win.

Cheers


If there any chance of liquid getting in a connection and the leak can't be prevented, I would move the connection, or solder and shrink wrap it. I'm not a big fan of greasing electrical connections.

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On Wednesday, April 6, 2016 at 7:43:17 PM UTC-4, Phil Hobbs wrote:
On 04/06/2016 08:42 AM, Tim R wrote:
On Tuesday, April 5, 2016 at 10:41:13 PM UTC-4, Ralph Mowery wrote:
"Rheilly Phoull" wrote in message
...

Have you got some dirt or oil/grease on the battery posts? That's what it
sounds like to me.

So when is grease on the terminals bad ??

When it gets between the battery post and the clamp.

If it is on the outside it is fine.


Conventional wisdom says when you tighten it down the grease gets squeezed out and there is direct metal to metal contact.

Whether that's based on data or not I don't know. But that's the way mechanics do it successfully.


Of course air is a better insulator than grease.

The actual metal-to-metal contact area is surprisingly small--it's
roughly equal to the total preload divided by the yield strength of the
weaker material. As long as the grease can get out of the way of the
high spots that actually do the conducting, it won't hurt the conductance..

What it will do is keep acid out of the joint, which is a win.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net


I have always put a coating of low viscosity grease on the battery and terminal, then wiped it out. The small of amount of lubricant left will be displaced at the actual contact points over the surface of both by the clamping force and left to fill the tiny pockets of what otherwise be air and moisture. I have never had a car battery contact problem ever.
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"Snuffy "Hub Cap" McKinney" wrote in
message ...
wrote in message
...
On Tuesday, April 5, 2016 at 1:19:36 PM UTC-4, Snuffy "Hub Cap" McKinney
wrote:
Out of the blue, I turned the ignition key and the started jerked and
stopped. Next turn solenoid clicked only. After that no sound on
turning key. No radio, panel lights, headlights, etc.

My guess at this point is that there is a bad negative ground.

No ongoing symptoms before today. Battery is new and checks out as fully
charged. Voltage OK at the solenoid relay on the inside wall.

Searched last night for a main fuse or fusible links. Wiring diagrams
show them but do not tell where to look for them. I assume close to the
battery -- will spend some time now looking and TS with a meter.

Any other suggestions? Thanks in advance.


They will be (typically) some sort of little black box mounted on the
firewall, or somewhere near the main fuse box or battery, it may look like
a fancy connector as well. But it will be there. There will be no such
thing on the ground side. Only on the + side.

Peter Wieck
Melrose Park, PA


Thanks, I looked and didn't see it yet. Hot battery terminal has one
large and one small wire, both going directly to the solenoid relay
mounted on the side wall. No voltage drop between battery post and relay
connection.


Ground the negative probe of a voltmeter to some clean metal part of the
engine block and the positive probe to the negative battery post - if the
post swings negative under load; you've got a bad earth.

On motorcycles, I've had bad earths between engine and frame - I've no idea
whether or not that can happen on a car. But I'd assume anythings possible.

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"Cursitor Doom" wrote in message
...
On Tue, 05 Apr 2016 17:51:18 -0500, amdx wrote:

Just to expound on the key off and on. If indeed the solenoid pulls
in, THEN is when you need to find the fault, current needs to flow to
find to find the bad connection. If you have 0.06 ohms of resistance in
a battery/starter circuit and the starter tries to draw 200 amps, there
is 12 volts dropped across your battery connection.*
You won't be able to measure 0.06 ohms.


At 200A, even one miliohm of connection resistance is going to waste 40W
of battery power.


Even "not that bad" dodgy connections can waste a fair bit of power.

Unless the engine bay is immaculately clean - that heat usually produces a
whisp of smoke.

40W is more than a lot of soldering irons, they'd smoke if they had traces
of oil on them.

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"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-Before and after
cleaning all the connections in the starting circuit the voltage drop
during starting is about the same - less than 3V.

I meant to add that all the connections were tight but several had various
levels of corrosion. After cleaning the overall .resistance from pos or
neg battery post to starter or block block went from around 1.9 to 1.4
ohms. That's not enough to prevent starting, but I suspect that one of
the .connections was intermittent.


Chances are the 1.9 and 1.4 ohms are some meter error problems such as the
leads not making good connection to the points they are measuring.

As large and as short as the wires are you should have way less than one ohm
of resistance, even less than .1 of an ohm.

If you had 1.4 ohms of resistance before the starter, it would never turn.
The starter has less than .1 ohms of resistance. Almost all the voltage
would be dropped in that 1.4 ohms and none left for the starter. With just
1.2 ohms of resistance you could only have 10 amps of current for the
starter, hardly enough to make it spin.

As this is electronics repair, anyone on here should be able to apply basic
Ohms law to see this.







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"Ralph Mowery" wrote in message ...

"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-Before and after
cleaning all the connections in the starting circuit the voltage drop
during starting is about the same - less than 3V.

I meant to add that all the connections were tight but several had various
levels of corrosion. After cleaning the overall .resistance from pos or
neg battery post to starter or block block went from around 1.9 to 1.4
ohms. That's not enough to prevent starting, but I suspect that one of
the .connections was intermittent.


Chances are the 1.9 and 1.4 ohms are some meter error problems such as the
leads not making good connection to the points they are measuring.

As large and as short as the wires are you should have way less than one ohm
of resistance, even less than .1 of an ohm.

If you had 1.4 ohms of resistance before the starter, it would never turn.
The starter has less than .1 ohms of resistance. Almost all the voltage
would be dropped in that 1.4 ohms and none left for the starter. With just
1.2 ohms of resistance you could only have 10 amps of current for the
starter, hardly enough to make it spin.

As this is electronics repair, anyone on here should be able to apply basic
Ohms law to see this.


Yes, you're right. The zero was offset on the meter. Measuring again showed resistance is lower than the detectable value for this meter. Thanks.

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"Snuffy "Hub Cap" McKinney" wrote in
message ...
Yes, you're right. The zero was offset on the meter. Measuring again
showed resistance is lower than the detectable value for this meter.
Thanks.


The old faital fail to zero out the ohm meter error. Hapens to the best of
us sometimes.



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"Ralph Mowery" wrote in message
...

"Snuffy "Hub Cap" McKinney" wrote
in message ...
Yes, you're right. The zero was offset on the meter. Measuring again
showed resistance is lower than the detectable value for this meter.
Thanks.


The old faital fail to zero out the ohm meter error. Hapens to the best
of us sometimes.


With my DMM I have to remember to subtract about 0.2R every time. But it
isn't always the same - sometimes its a few R, very occasionally it actually
reads zero with the probes shorted.

Its probably the sockets in the front so new leads/probes probably wouldn't
fix it. I have newer meters, but I've had that on a long time and its become
comfortable.

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"Ian Field" wrote in message
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With my DMM I have to remember to subtract about 0.2R every time. But it
isn't always the same - sometimes its a few R, very occasionally it
actually reads zero with the probes shorted.

Its probably the sockets in the front so new leads/probes probably
wouldn't fix it. I have newer meters, but I've had that on a long time and
its become comfortable.


Some of my meters have a button on them that will set the display to 'zero'
for most functions.

Some of the other inexpensive DMMs do not have any way to zero out the
resistance.
I even had an old one somewhere that had a zero adjustment pot similar to
my trusty Simpson 260 analog.


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"Ralph Mowery" wrote in message ...

"Ian Field" wrote in message
news


With my DMM I have to remember to subtract about 0.2R every time. But it
isn't always the same - sometimes its a few R, very occasionally it
actually reads zero with the probes shorted.

Its probably the sockets in the front so new leads/probes probably
wouldn't fix it. I have newer meters, but I've had that on a long time and
its become comfortable.


Some of my meters have a button on them that will set the display to 'zero'
for most functions.

Some of the other inexpensive DMMs do not have any way to zero out the
resistance.
I even had an old one somewhere that had a zero adjustment pot similar to
my trusty Simpson 260 analog.


This meter was one of the extra high quality super accurate types that Harbor Freight gives away free! :O)



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"Snuffy "Hub Cap" McKinney" wrote in
message ...
"Ralph Mowery" wrote in message
...

"Ian Field" wrote in message
news


With my DMM I have to remember to subtract about 0.2R every time. But it
isn't always the same - sometimes its a few R, very occasionally it
actually reads zero with the probes shorted.

Its probably the sockets in the front so new leads/probes probably
wouldn't fix it. I have newer meters, but I've had that on a long time
and
its become comfortable.


Some of my meters have a button on them that will set the display to
'zero'
for most functions.

Some of the other inexpensive DMMs do not have any way to zero out the
resistance.
I even had an old one somewhere that had a zero adjustment pot similar to
my trusty Simpson 260 analog.


This meter was one of the extra high quality super accurate types that
Harbor Freight gives away free! :O)
---------------------------------

Otherwise known as a "transfer standard".



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On 04/07/2016 05:31 PM, tom wrote:
"Snuffy "Hub Cap" McKinney" wrote in
message ...
"Ralph Mowery" wrote in message
...

"Ian Field" wrote in message
news


With my DMM I have to remember to subtract about 0.2R every time. But it
isn't always the same - sometimes its a few R, very occasionally it
actually reads zero with the probes shorted.

Its probably the sockets in the front so new leads/probes probably
wouldn't fix it. I have newer meters, but I've had that on a long time
and
its become comfortable.


Some of my meters have a button on them that will set the display to
'zero'
for most functions.

Some of the other inexpensive DMMs do not have any way to zero out the
resistance.
I even had an old one somewhere that had a zero adjustment pot similar to
my trusty Simpson 260 analog.


This meter was one of the extra high quality super accurate types that
Harbor Freight gives away free! :O)
---------------------------------

Otherwise known as a "transfer standard".



random number generator

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"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-
This meter was one of the extra high quality super accurate types that
Harbor Freight gives away free! :O)


I have several of them. They are not too bad. I checked them using a Fluke
that was verified by a standard at work that was tracable to the NIST.

There is an adjustment inside them if you want to calibrate a certain scale.

They are almost worth twice the price we paid for them :-)




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"Ralph Mowery" wrote in message ...

"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-
This meter was one of the extra high quality super accurate types that
Harbor Freight gives away free! :O)


I have several of them. They are not too bad. I checked them using a Fluke
that was verified by a standard at work that was tracable to the NIST.

There is an adjustment inside them if you want to calibrate a certain scale.

They are almost worth twice the price we paid for them :-)


Yes, they're good for general work. One tip - if the meter starts to slide off the table, let it hit the ground and don't grab one of the probes. The probe wires are about the thickness of a hair.

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"Ralph Mowery" wrote in message
...

"Snuffy "Hub Cap" McKinney" Snuffy-Hub-Cap@Livebait-
This meter was one of the extra high quality super accurate types that
Harbor Freight gives away free! :O)


I have several of them. They are not too bad. I checked them using a
Fluke that was verified by a standard at work that was tracable to the
NIST.

There is an adjustment inside them if you want to calibrate a certain
scale.


My first ever DMM came out the bin where I worked at the time, resistance
and ACV ranges were dead.

Inside was an LSI chip and a socketed dual op-amp - nothing to lose, I tried
changing the op-amp.

There was a preset pot on the board, so with the missing ranges restored, I
was able to borrow a traceable certificate instrument to set it up by.

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