Won't turn over when hot
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2nd Gear
Joined: Feb 2016
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Won't turn over when hot
My 1968 stingray, 327, will turn over just fine when cold, but not hot. I can't barely turn it off anywhere I go do to it not wanting to turn back over. Living in the south, it gets very hot and this is obviously a problem. I have already wrapped my starter in a 'versashield' heat wrap and still having the same problem. I also have hooker headers, but I'm not wrapping them. Any advice?
Last edited by Healyjm; Feb 28, 2016 at 04:51 PM.
Drifting
Joined: Jul 2011
Posts: 1,697
Likes: 139
From: Syracuse NY
My 1968 stingray, 327, will turn over just fine when cold, but not hot. I can't barely turn it off anywhere I go do to it not wanting to turn back over. Living in the south, it gets very hot and this is obviously a problem. I have already wrapped my starter in a 'versashield' heat wrap and still having the same problem. I also have hooker headers, but I'm not wrapping them. Any advice?
Burning Brakes
Joined: Aug 2003
Posts: 1,060
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From: Ocean Springs, MS
St. Jude Donor '07
Advanced
Joined: Dec 2012
Posts: 53
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From: North East Ohio
I am not sure if this is your problem, is this an old starter motor or new? If it is an old starter, I had the same problem years ago (40 years) and it was a bronze 99 cent bushing at the far end of the starter motor that was worn. I too tried everything but this was the problem, back then I couldn't afford a new starter so tried this cheap fix. That was in the day when we fixed things due to cost vs buying rebuilt or new. Hope this helps.
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Here in Texas it gets warm also. I had this exact problem and here are all the things I did to resolve it. If I were you I would start with the easiest/cheapest and see what works.
1. Check for motor to frame ground wire at driver side motor mount. I would replace it with a new, 4 ga or larger wire.
2. I added an additional 4 ga braided ground wire directly on the starter then over to a clean spot on the frame.
3. When I replaced the starter I went with a pmgr unit. Ask for a 2000 Caddy Escalade starter. Smaller. lighter, more power.
4. New and larger gauge copper cables from the battery to the starter, both pos and neg. The originals on my car were copper clad aluminum and were corroded too.
5. New larger gauge ground from bat to frame.
6. 1000 Cranking amp battery.
Try replacing and adding grounds to the starter first and check your ground at the battery to frame and see if that helps first.
Hope this helps.
John
1. Check for motor to frame ground wire at driver side motor mount. I would replace it with a new, 4 ga or larger wire.
2. I added an additional 4 ga braided ground wire directly on the starter then over to a clean spot on the frame.
3. When I replaced the starter I went with a pmgr unit. Ask for a 2000 Caddy Escalade starter. Smaller. lighter, more power.
4. New and larger gauge copper cables from the battery to the starter, both pos and neg. The originals on my car were copper clad aluminum and were corroded too.
5. New larger gauge ground from bat to frame.
6. 1000 Cranking amp battery.
Try replacing and adding grounds to the starter first and check your ground at the battery to frame and see if that helps first.
Hope this helps.
John
Advanced
Joined: Apr 2013
Posts: 70
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From: Adelaide South Australia
Another path is to check the carburetor temperature after a drive and then a heat soak. Heat has always been a bugbear for the Quadrajet, and made worse by the confined engine bay and fiberglass hood in C3.
If the carburetor is hot to touch after a full warm up, drive and 20 minute heat soak, then you might get a phenolic spacer to keep the Quad cooler.
This worked for me on my 78, which also ran perfectly but would struggle with a hot start.
I think the big battery and starter solutions work primarily by running the engine harder on a hot start, and just forcing it to ignite. It works, but might be unnecessary if you have a heat problem at the carb.
War means you can hold your hand on the carb for as long as you like.
Hot means you must remove it after a few seconds or get a burn. Not exact science, but you know what I mean.
Quads do not manage heat well. They are a very efficient and complex carburetor, but don't hold a lot of fuel, which is part of the problem. Lots of metal, and little liquid fuel means they can get hot and hold heat for a long time.
If the carburetor is hot to touch after a full warm up, drive and 20 minute heat soak, then you might get a phenolic spacer to keep the Quad cooler.
This worked for me on my 78, which also ran perfectly but would struggle with a hot start.
I think the big battery and starter solutions work primarily by running the engine harder on a hot start, and just forcing it to ignite. It works, but might be unnecessary if you have a heat problem at the carb.
War means you can hold your hand on the carb for as long as you like.
Hot means you must remove it after a few seconds or get a burn. Not exact science, but you know what I mean.
Quads do not manage heat well. They are a very efficient and complex carburetor, but don't hold a lot of fuel, which is part of the problem. Lots of metal, and little liquid fuel means they can get hot and hold heat for a long time.
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Drifting
Joined: Aug 2009
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From: new iberia la
If its not your ground cable,or the missing heat shield on the Solenoid, its your starter . You don t need a mini Hi-Torq .. for decades, our engines started just fine when hot with a regular old GM starter. Buy one if you like, not because you must have it
Safety Car
Joined: Sep 2007
Posts: 4,458
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From: Indy Indiana
if it starts fine when cold then your starter is fine.. it is just when it gets hot.. heat causes the starter to require lots of extra amps to crank your car over.. that is why.
replacing the starter with newer or a high torque will work to a great degree.. but you must also have the biggest and the best amp battery you can find.
get you a 1000 amp battery. it will solve a multitude of issues.
A battery loses 10% of its power a year. a 500 amp battery that is 5 years old will not crank over a hot engine. even though it may crank over a cold engine. make sure your battery is also fully charged. if you don't drive your car enough then your battery will slowly get weaker and weaker. it just might need a deep charge.
replacing the starter with newer or a high torque will work to a great degree.. but you must also have the biggest and the best amp battery you can find.
get you a 1000 amp battery. it will solve a multitude of issues.
A battery loses 10% of its power a year. a 500 amp battery that is 5 years old will not crank over a hot engine. even though it may crank over a cold engine. make sure your battery is also fully charged. if you don't drive your car enough then your battery will slowly get weaker and weaker. it just might need a deep charge.
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Last edited by Peterbuilt; Feb 29, 2016 at 09:49 PM.
Drifting
Joined: Sep 2014
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From: Long beach NY
St. Jude Donor '15-'16, '18
Used to have same problem a lifetime ago, kept 2x4 in car to give it some love taps, as stated previously starter was bad.
But i would not have any starter engagement at all, i dont know if you get any crank or a weak one.
Good luck
But i would not have any starter engagement at all, i dont know if you get any crank or a weak one.
Good luck
Last edited by Calo69; Mar 1, 2016 at 01:16 AM. Reason: Add
Drifting
Joined: Apr 2002
Posts: 1,720
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From: Manhattan Beach Ca
Just went through this last week. Same thing. Was battery for me.
Check battery with multimeter and see what voltage it reads. If less than roughly 12.2 its probably battery. Also make sure altenator is ok by taking negative off battery while engine is running and see if engine stays running, or use multimeter while running and should be 14.0 something. Just a quick check.
If all checks out then its starter for sure.
Check battery with multimeter and see what voltage it reads. If less than roughly 12.2 its probably battery. Also make sure altenator is ok by taking negative off battery while engine is running and see if engine stays running, or use multimeter while running and should be 14.0 something. Just a quick check.
If all checks out then its starter for sure.
Last edited by Surfer69; Mar 1, 2016 at 10:59 AM.
Safety Car
Joined: Jan 2009
Posts: 4,000
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From: New York
My 1968 stingray, 327, will turn over just fine when cold, but not hot. I can't barely turn it off anywhere I go do to it not wanting to turn back over. Living in the south, it gets very hot and this is obviously a problem. I have already wrapped my starter in a 'versashield' heat wrap and still having the same problem. I also have hooker headers, but I'm not wrapping them. Any advice?
Check the usual suspects such as grounds And the starter itself.
Also check initial timing that will cause a motor to crank impossibly hard when warm if it is advanced to far .
Instructor
Joined: Sep 2015
Posts: 249
Likes: 32
From: Cypress TX
Starter solenoid on old GM starters are also a big weak spot. The mini permanent magnet gear reduction starters spin the motor faster and pull less current. Notice, GM still use them. Mopar has always been gear reduction.
Melting Slicks
Joined: May 2002
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From: Sulphur LA
St. Jude Donor '05-'06,'11,'13-'14,'16,'18,'19,'24, '25
Do a little troubleshooting,
Check the voltage at the starter with a volt meter with engine hot and someone cranking it over, ground lead on starter body near mounting bolt and positive lead on main cable lug form battery. If the voltage is less than 10 you have a problem. Move the ground lead to a known good ground and check the voltage while cranking again, if voltage is higher then you have a starter grounding issue. If voltage is still low you need to check the battery and cable connections going to the starter.
If the voltage is over 10 when hot and is not turning over check the positive lug on the end of the solenoid feeding the starter motor while cranking. If the voltage is below 10 you have a solenoid issue. If the voltage is above 10 you more than likely have a starter issue.
Neal
Check the voltage at the starter with a volt meter with engine hot and someone cranking it over, ground lead on starter body near mounting bolt and positive lead on main cable lug form battery. If the voltage is less than 10 you have a problem. Move the ground lead to a known good ground and check the voltage while cranking again, if voltage is higher then you have a starter grounding issue. If voltage is still low you need to check the battery and cable connections going to the starter.
If the voltage is over 10 when hot and is not turning over check the positive lug on the end of the solenoid feeding the starter motor while cranking. If the voltage is below 10 you have a solenoid issue. If the voltage is above 10 you more than likely have a starter issue.
Neal