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Old 10-14-2018, 07:07 PM   #26
geezer#99
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Re: Hot starter motor

Could be it’s causing some resistance but I think your timing might be suspect.
I’ve installed an interrupter switch in the power line to the distributor. Get it spinning over and flip the switch and it’ll fire right up.

What is your timing like?
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Old 10-14-2018, 08:14 PM   #27
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Re: Hot starter motor

Quote:
Originally Posted by geezer#99 View Post
Water has itís uses but not for pouring on hot parts.
The thermal shock will crack cast iron starter noses.
And create an excellent ground path for your 12v power supply on the starter.
If you want to cool the starter you can use a wet cloth on it.
Never pour. Dribble.

Down the back of the head works. I've done it many times. Since my truck handled water puddles and rain with no trouble I didn't think about ground issues.
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Old 10-14-2018, 09:16 PM   #28
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Re: Hot starter motor

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Originally Posted by geezer#99 View Post
Could be itís causing some resistance but I think your timing might be suspect.
Iíve installed an interrupter switch in the power line to the distributor. Get it spinning over and flip the switch and itíll fire right up.

What is your timing like?
The timing has been adjusted a couple of times by a pretty reputable macanic. It was a couple of times because of a leak in the intake and then the distributor gasket and also because of some sputtering/sneezing sounds under hard acceleration.
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Old 10-14-2018, 09:26 PM   #29
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Re: Hot starter motor

When ever I had the mechanic look at it, it never happened. So they said it sounds like the battery and the timing. Seams to work for a while and then start having the problem again. I have a feeling it is because it is not getting enough power. Something is keeping power from the starter.
I don’t think it is the timing because it effects the turning over of the starter motor.
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Old 10-14-2018, 09:28 PM   #30
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Re: Hot starter motor

I don't care what your mechanic says, it sounds like a timing issue. You stated it wouldn't turn over when hot but you disconnected the distributor and it turned over fine, that says the timing is too high.
This is how we use to set our timing in the old days. Get the motor good and hot and keep turning the timing up until it cranks slow then back it up until it cranked like it should and leave it. "Warning" this doesn't work so good on modern motors with vortec heads.
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Old 10-14-2018, 10:02 PM   #31
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Re: Hot starter motor

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... "Warning" this doesn't work so good on modern motors ...
Olaf voice: I don't have a skull ... or bones.
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Old 10-15-2018, 11:49 AM   #32
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Re: Hot starter motor

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Originally Posted by garyd1961 View Post
I don't care what your mechanic says, it sounds like a timing issue. You stated it wouldn't turn over when hot but you disconnected the distributor and it turned over fine, that says the timing is too high.
This is how we use to set our timing in the old days. Get the motor good and hot and keep turning the timing up until it cranks slow then back it up until it cranked like it should and leave it. "Warning" this doesn't work so good on modern motors with vortec heads.
I have 2 questions. They are legitimate questions so don't take them the wrong way.

1. Why would the increase and lowering of timing cause the starter motor to slow down or speed up? Forgive me if this seems like a stupid question but I don't know much.

2. After I plugged the distributor back in while the engine was still hot it cranked over fine. Would that have happened if it was a timing issue? It seems like if it was the timing that was off it would go back to cranking slow again.

Thank you for your help. I am not trying to be difficult or argumentative.
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Old 10-15-2018, 12:57 PM   #33
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Re: Hot starter motor

if Your timing is too far advanced you start the burn too soon. The piston is still rising at that point and the combustion process tries to push it back down. The starter has to work harder to push the piston up. When the starter works harder it creates more heat. More heat in the starter makes it turn slower.

2. It doesn’t take long for the starter to cool off enough to crank better. In your case about the amount of time to plug the wire back in.
Your timing’s likely close. Pull it back a couple degrees.
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Old 10-15-2018, 12:59 PM   #34
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Re: Hot starter motor

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Originally Posted by forestb View Post
I have 2 questions. They are legitimate questions so don't take them the wrong way.

1. Why would the increase and lowering of timing cause the starter motor to slow down or speed up? Forgive me if this seems like a stupid question but I don't know much.

2. After I plugged the distributor back in while the engine was still hot it cranked over fine. Would that have happened if it was a timing issue? It seems like if it was the timing that was off it would go back to cranking slow again.

Thank you for your help. I am not trying to be difficult or argumentative.
No harm in asking.

I'm sure others will be along shortly to provide a more detailed or accurate reply but I'll take a swing at it.

1.) When the timing is too far advanced the plugs will fire too early in the compression stroke causing the engine to kick back against the starter. It's more noticeable when the motor is already hot.

2.) This is a SWAG but as mentioned earlier, I'd pull the cap and make sure the advance moves freely and not binding up.

Timing advances and retards during normal driving. If the distributor is hung too far advanced when you shut it off it will still be advanced when you try a restart. In the process of trying a few times to start it the advance returns to 12-14 BTC or whatever the mechanic set it to and it starts. This leads to a lot of head scratching.

It only takes a couple of minutes to pull the cap and verify that the advance moves freely and nothing is binding up.

One more thing: If it's kicking back against the starter you can be sure it's pulling chingos of amps from the battery.
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Old 10-15-2018, 02:42 PM   #35
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Re: Hot starter motor

Thanks I will take a look. My distributor is leaking where it goes into the intake. Would that have any relevance to my problem?
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Old 10-15-2018, 03:17 PM   #36
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Re: Hot starter motor

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Thanks I will take a look. My distributor is leaking where it goes into the intake. Would that have any relevance to my problem?
No it won’t.
You might have a bad gasket if it leaks a tiny bit.
If it leaks a bunch you have a crankcase pressure problem.
Or your oil pressure sender is leaking. It’s right beside the distributor.
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Old 10-22-2018, 08:22 PM   #37
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Re: Hot starter motor

Just wondering if you ever got this straighten out?
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Old 10-22-2018, 09:28 PM   #38
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Re: Hot starter motor

No I had to take the truck back to the painter to fix all the problems that are springing up in the paint. So it will be a while. I talked to the guy that installed my new wiring. He recommended all the things that you all did.
1. check the timing.
2. Check the battery.
3. Installed a thicker battery cable.
4. Connect the bay ground to the starter bolt instead of the block.
5. Put some heat wrap around the starter motor.
He is right down the street from the painter so while it’s there he’s going to check the battery and also have an engine tooner that he uses on his builds come over and toon the engine. It is going to be a while before I get the truck back. I will try to remember to update you all.
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Old 05-25-2019, 11:27 PM   #39
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Re: Hot starter motor

So I added a 1 gauge battery and ground cable. I also added a ground strap that goes from the frame to the same spot that the battery ground bolts into the engine block. Hopefully this will help I also got some insulation for around the starter but have not gotten a chance to install it.
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Old 06-10-2019, 12:03 AM   #40
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Re: Hot starter motor

I added another heavy duty ground strap on the driver side that goes from the block to the frame and a standard size one from the frame to the cab. I hope that will help me not get shocked when I push on the horn button. It seems to be starting better when hot sense I beefed up the electrical system. I still am planning on wrapping the starter motor in heat shielding just in case the problem is caused by heat soak.
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Old 06-10-2019, 12:53 AM   #41
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Re: Hot starter motor

Assuming heat soak (one of the less likely issues) for no particular reason is a mistake. Basically, it means you have a problem and decided the cause w/o a reason. The same goes for any issue.

For the starter (slow crank), the ground should go from the battery to the block. The + cable obviously goes from the battery to the solenoid. Good battery cables are needed (good and new may not be the same thing).
You can use one lead of a jumper cable to test the ground or + side.
You really need to know what the battery voltage is at rest, under load and when the alt is charging it. That means you need a decent voltmeter (DVM). A charged battery is 12.6V, Charging 13.5V or a bit more. You might also measure end to end from each battery cable terminal on the same cable.
As people stated long ago, initial timing too advanced, will cause a slow crank.

I read the whole thread and don't think I saw any voltage measurements. You can swap parts for years (as you have) and not solve the problem. Maybe it's time to troubleshoot the issue... Sorry if that's pushy but it's still a fact.

Last edited by franken; 06-10-2019 at 01:04 AM.
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Old 06-10-2019, 01:59 AM   #42
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Re: Hot starter motor

I didn't read the entire thread but have to ask this. I know your engine is grounded to the frame in more than one place but what have you done with the ground cable coming from the batt?

Do you have a new ground cable from the neg post to the engine? I ask because my 74 had a similar issue. The cables looked perfect and passed voltage perfectly fine - but the neg cable could not pass enough current to spin the engine every time. The neg cable looked and felt perfect but was bad.

I highly suggest getting a volt meter, even a $5 one at harbor freight, and do as franken and others have said and check your voltages. Also check the resistance in the cables. Just because they look good doesn't mean they are.
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Old 06-10-2019, 11:51 AM   #43
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Re: Hot starter motor

It has a new 1 gauge battery negative cable (good brand not just new, can't remember the name right now) that connects to the block and a large ground strap that goes from the same hole in the block to the frame. I will check my voltages if I am still having issues. I don't know if this means anything but when the engine is running my voltmeter gauge shows 14 volts. When I crank it used to go down to zero. I have not checked what it does while cranking and the ground straps are installed.
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Old 06-10-2019, 12:17 PM   #44
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Re: Hot starter motor

The cables are American Autowire Battery Cables.
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Old 06-11-2019, 12:26 AM   #45
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Re: Hot starter motor

Quote:
Originally Posted by franken View Post
Assuming heat soak (one of the less likely issues) for no particular reason is a mistake. Basically, it means you have a problem and decided the cause w/o a reason. The same goes for any issue.

For the starter (slow crank), the ground should go from the battery to the block. The + cable obviously goes from the battery to the solenoid. Good battery cables are needed (good and new may not be the same thing).
You can use one lead of a jumper cable to test the ground or + side.
You really need to know what the battery voltage is at rest, under load and when the alt is charging it. That means you need a decent voltmeter (DVM). A charged battery is 12.6V, Charging 13.5V or a bit more. You might also measure end to end from each battery cable terminal on the same cable.
As people stated long ago, initial timing too advanced, will cause a slow crank.

I read the whole thread and don't think I saw any voltage measurements. You can swap parts for years (as you have) and not solve the problem. Maybe it's time to troubleshoot the issue... Sorry if that's pushy but it's still a fact.
Thanks for your advice. What do you mean by using one lead of a jumper cable to test the ground or + side. How do I do that? Also how do I test it under load?
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