Won't start when hot! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

chevy72pu · 05-20-2012, 01:46 PM

Ok, so the rebuilt 350 runs like a top, no overheating, no leaks. All is well till I shut it off after more than 7-8 miles of driving. It will not restart until it sits for 30 mins or so. The battery turns her over fine when she is cold, but can't manage to do so when the engine is hot. Swapped the battery out of Lil' Red and the same thing happened. We put double hump heads on the 350, so I'm wondering, do I need a new stronger battery or a high torque starter? BTW it will crank with a jump start even when it is hot. I had Advance Auto Parts check it and the print out showed a 25 amp drop on the battery and the alternator is fine at idle.

DT1 · 05-20-2012, 02:31 PM

Same thing happened with mine a while back. It would crank very sluggishly. I thought the timing was just too far advanced but It was just a tired starter. I changed it out and it cranks like crazy now.

Gene · 05-20-2012, 02:37 PM

Make sure all your connections are good, I had same problem but my hot wire from battery was hanging on by only a few strands. It looked ok but when I took starter loose the wire just broke in half.

**LockDoc** · 05-20-2012, 02:56 PM

-
I would say it is one of two things.

Gas is boiling in the carb float bowl or the starter and solenoid are suffering from heat soak. When the starter and solenoid get hot it degrades performance.

I had the starter problem so I decided to get one of the mini starters so it would have more air space around the starter. I had no more hard starting problems after that.

Usually with the gas boiling in the float bowl problem it will show up after setting and idling for a period of time and the temp rises. When you accelerate after setting at idle for a while the engine will run fine for a minute or so then start running really crappy and will not accelerate. It acts like it is starving for fuel, which it is. You can usually cure this problem by installing a 3/4 or 1" phenolic spacer under the carb.

Just a couple of things to think about.

LockDoc

**70cst** · 05-21-2012, 10:36 PM

Quote:

Originally Posted by LockDoc

-
I would say it is one of two things.

Gas is boiling in the carb float bowl or the starter and solenoid are suffering from heat soak. When the starter and solenoid get hot it degrades performance.

I had the starter problem so I decided to get one of the mini starters so it would have more air space around the starter. I had no more hard starting problems after that.

Usually with the gas boiling in the float bowl problem it will show up after setting and idling for a period of time and the temp rises. When you accelerate after setting at idle for a while the engine will run fine for a minute or so then start running really crappy and will not accelerate. It acts like it is starving for fuel, which it is. You can usually cure this problem by installing a 3/4 or 1" phenolic spacer under the carb.

Just a couple of things to think about.

LockDoc

I had the exact symptoms and it was the starter with Heat Soak problems.

**Boog** · 05-21-2012, 10:43 PM

If the engine spins over fine cold but grunts when fully warmed up it's most generally the starter heat soak problem. If the engine spins over normally when cold or fully warmed up but won't start up it's generally a fuel issue.

502ms · 05-21-2012, 10:46 PM

Quote:

Originally Posted by Boog

If the engine spins over fine cold, but grunts when fully warmed up it's most generally the starter heat soak problem.

Agreed
Posted via Mobile Device

oldgoalie · 05-20-2012, 05:08 PM

I had a 69 c20 that did that. It was a bad battery cable. It was the pos cable. It looked good but it was coroded inside the sheathing about 10" from where it bolts to the starter. I think maybe, the heat from the exhaust. Replaced it, no more problem.

cdowns · 05-20-2012, 05:17 PM

in the edelbrock carb installation instructions they warn of this problem and suggest using a phenolic carb spacer

Gene · 05-20-2012, 05:46 PM

Quote:

Originally Posted by cdowns

in the edelbrock carb installation instructions they warn of this problem and suggest using a phenolic carb spacer

I installed one under my edelbrock Carb and it did help some, but the problem is still there.
Posted via Mobile Device

lil hoodlum · 05-20-2012, 06:03 PM

Quote:

Originally Posted by Gene

I installed one under my edelbrock Carb and it did help some, but the problem is still there.
Posted via Mobile Device

I did the same for mine as well. I also apperently had mine air/fuel ratio too lean. I guess that makes it run a little hotter.

Keith

Andy4639 · 05-20-2012, 10:25 PM

Well mine is fuel injected so I know it wasn't the boiling. After swapping to the Orileays super mini starter mine has never had trouble again.

Here is the thread on the starter. Over a year now and it's never gave me a bit of trouble even after driving hours.

http://67-72chevytrucks.com/vboard/s....php?p=4151565

50bomb · 05-21-2012, 08:58 AM

My grandpa's 64 chevy truck does the same thing almost everytime he comes over here to my house. It happen again yesterday so it is on our driveway right now. How about the Distributor? do you think it could be the ignition rotor in there?maybe not tight enough or the lil chrome arm is not far/closed enough? No sure which one. He has a sbc350/th350. Grandpa made me laugh when he was walkin away from his truck. He said some choice words in spanish. I feel his pain. Put so much money in them and they want more attention haha.

scrappy ron · 05-21-2012, 09:49 AM

Quote:

Originally Posted by 50bomb

My grandpa's 64 chevy truck does the same thing almost everytime he comes over here to my house. It happen again yesterday so it is on our driveway right now. How about the Distributor? do you think it could be the ignition rotor in there?maybe not tight enough or the lil chrome arm is not far/closed enough? No sure which one. He has a sbc350/th350. Grandpa made me laugh when he was walkin away from his truck. He said some choice words in spanish. I feel his pain. Put so much money in them and they want more attention haha.

i bet you any thing its the coil i would check it. its a vary comin proble

bbadfred · 05-21-2012, 10:22 AM

No matter what you do find get a mini starter anyway! You will never regret it!!

gcburdic · 05-21-2012, 10:24 AM

check this thread for a mini starter that weighs just 7lbs and is $60...http://67-72chevytrucks.com/vboard/s...d.php?t=521843.....This will be the route I go next time I need tho change out the starter.....better than laying on my back trying to get that 20lb starter in place

Let us know what works for ya!!!

coop34 · 05-21-2012, 01:44 PM

Quote:

Originally Posted by gcburdic

check this thread for a mini starter that weighs just 7lbs and is $60...http://67-72chevytrucks.com/vboard/s...d.php?t=521843.....This will be the route I go next time I need tho change out the starter.....better than laying on my back trying to get that 20lb starter in place

Let us know what works for ya!!!

I had the same problem, and switched to this mini starter. Has started up every time since. $60 to my door.

jchav62 · 05-21-2012, 10:24 AM

The timing may just be a little too advanced. When I first saw your pic and saw the Edelbrock carb, I was going to blame it (heat soak) but after reading your post, I realized that's not your case.

Also, like the other's said, check your positive cable from the start... and make sure the terminals are clean and tight.

Good luck... JC62

bowtiecharlie · 05-21-2012, 07:52 PM

I had a 72 short bed that would not "crank over when hot"! You could jump the starter with a screwdriver and it would start, but not with the key!! After weeks of new parts ,battery,starter,ns switch, ground wires to the frame and fire wall ,I found that the wire that runs from the Positive batt terminal to the fender (black junction block) was shot!! I cut and soldered a new wire terminal on it and it was good as new!! You should also have one from the Negitive cable to the fender direct,with no junction block!!

fastwillie 696969 · 05-21-2012, 08:43 PM

good thing its not a blower engine

chevy72pu · 05-21-2012, 10:27 PM

The timing thing could be it. We advanced it to the limit and then backed it down a hair. I didn't mention this earlier, but it does "diesel" for a few seconds when you shut it off. I usually just ease out on the clutch to stop it. I'm not gonna change too many things at once so I can tell what corrects the problem.

71swb4x4 · 05-21-2012, 10:40 PM

Quote:

Originally Posted by chevy72pu

The timing thing could be it. We advanced it to the limit and then backed it down a hair. I didn't mention this earlier, but it does "diesel" for a few seconds when you shut it off. I usually just ease out on the clutch to stop it. I'm not gonna change too many things at once so I can tell what corrects the problem.

Before I even read this post I was going to suggest timing as a couple of others have. I had a 72 that did exactly what you describe, and it was the timing, I had advanced it too far. It would also diesel sometimes when shutting it down.

doubleb's69 · 05-21-2012, 10:31 PM

Nice looking engine bay. Is your lower radiator hose resting against your fuel line. If so that would really aid in the transfer of heat to your fuel and like LockDoc said it would boil while idleing. My truck would run fine once started as well but it would eventually just shut off with the factory cast iron intake and then I would have to let it sit and cool down to get it going again. I put a new aluminum intake on and put on a set of cross over block off intake gaskets on and it seems to be ok now.

67ChevyRedneck · 05-21-2012, 10:58 PM

You need a solenoid heat shield. (the one below is just a generic search, but the GM one looks just like it... it may be the correct one...)

http://shop.advanceautoparts.com/web...___#fragment-2

CountofMonteCarlo84 · 08-03-2017, 10:43 AM

I have had similar symptoms with a fuel pump going bad.

05-20-2012, 01:46 PM	#1
chevy72pu Registered User Join Date: Jan 2009 Location: Sandersville, GA Posts: 298	Won't start when hot! Ok, so the rebuilt 350 runs like a top, no overheating, no leaks. All is well till I shut it off after more than 7-8 miles of driving. It will not restart until it sits for 30 mins or so. The battery turns her over fine when she is cold, but can't manage to do so when the engine is hot. Swapped the battery out of Lil' Red and the same thing happened. We put double hump heads on the 350, so I'm wondering, do I need a new stronger battery or a high torque starter? BTW it will crank with a jump start even when it is hot. I had Advance Auto Parts check it and the print out showed a 25 amp drop on the battery and the alternator is fine at idle. Attached Images __________________ How 'Bout them Dawgs! '10 Traverse LTZ 03 Silverado Z71 ext cab 99 Yamaha Grizzly 600 72 C10 350/350 sportside bed. 68 C30 flatbed. 350 4-speed. "I've got a good memory, it's just short!"

05-20-2012, 02:31 PM	#2
DT1 Registered User Join Date: Oct 2009 Location: Gardnerville Nv No Mo Cali!! Posts: 869	Re: Won't start when hot! Same thing happened with mine a while back. It would crank very sluggishly. I thought the timing was just too far advanced but It was just a tired starter. I changed it out and it cranks like crazy now.

05-20-2012, 02:37 PM	#3
Gene Registered User Join Date: Aug 2002 Location: Muskogee, Oklahoma Posts: 2,914	Re: Won't start when hot! Make sure all your connections are good, I had same problem but my hot wire from battery was hanging on by only a few strands. It looked ok but when I took starter loose the wire just broke in half. __________________ 1971 SWB 4X4 Build BOARD MEMBER #5448 BOOMER SOONER!!!!

05-20-2012, 02:56 PM	#4
LockDoc The Older Generation Join Date: Aug 2006 Location: Montezuma, Iowa Posts: 25,771	Re: Won't start when hot! - I would say it is one of two things. Gas is boiling in the carb float bowl or the starter and solenoid are suffering from heat soak. When the starter and solenoid get hot it degrades performance. I had the starter problem so I decided to get one of the mini starters so it would have more air space around the starter. I had no more hard starting problems after that. Usually with the gas boiling in the float bowl problem it will show up after setting and idling for a period of time and the temp rises. When you accelerate after setting at idle for a while the engine will run fine for a minute or so then start running really crappy and will not accelerate. It acts like it is starving for fuel, which it is. You can usually cure this problem by installing a 3/4 or 1" phenolic spacer under the carb. Just a couple of things to think about. LockDoc __________________ Leon Locksmith, Specializing In Antique Trucks, Automobiles, & Motorcycles (My Dually Pickup Project Thread) http://67-72chevytrucks.com/vboard/s...d.php?t=829820 -

05-21-2012, 10:43 PM	#6
Boog laying low Join Date: Mar 2001 Location: Searcy, Ark. USA Posts: 13,514	Re: Won't start when hot! If the engine spins over fine cold but grunts when fully warmed up it's most generally the starter heat soak problem. If the engine spins over normally when cold or fully warmed up but won't start up it's generally a fuel issue. __________________ Boog 69 Chevy stepside, 358/T350, 4.11 posi, 4.5/4 drop, rallys, poboy driver primer is finer 91 Chevy sportside, Tahoe, Yukon & GMC Crewcab All GM..'nuff said. I stand for the flag and kneel at the cross

05-20-2012, 05:08 PM	#8
oldgoalie Registered User Join Date: Feb 2012 Location: Wenatchee, Washington Posts: 92	Re: Won't start when hot! I had a 69 c20 that did that. It was a bad battery cable. It was the pos cable. It looked good but it was coroded inside the sheathing about 10" from where it bolts to the starter. I think maybe, the heat from the exhaust. Replaced it, no more problem.

05-20-2012, 05:17 PM	#9
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: Won't start when hot! in the edelbrock carb installation instructions they warn of this problem and suggest using a phenolic carb spacer __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

05-20-2012, 10:25 PM	#12
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,945	Re: Won't start when hot! Well mine is fuel injected so I know it wasn't the boiling. After swapping to the Orileays super mini starter mine has never had trouble again. Here is the thread on the starter. Over a year now and it's never gave me a bit of trouble even after driving hours. http://67-72chevytrucks.com/vboard/s....php?p=4151565 __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

05-21-2012, 08:58 AM	#13
50bomb Registered User Join Date: Jul 2010 Location: Hemet,Ca Posts: 1,502	Re: Won't start when hot! My grandpa's 64 chevy truck does the same thing almost everytime he comes over here to my house. It happen again yesterday so it is on our driveway right now. How about the Distributor? do you think it could be the ignition rotor in there?maybe not tight enough or the lil chrome arm is not far/closed enough? No sure which one. He has a sbc350/th350. Grandpa made me laugh when he was walkin away from his truck. He said some choice words in spanish. I feel his pain. Put so much money in them and they want more attention haha. __________________ Stovebolt-It is painted

05-21-2012, 10:22 AM	#15
bbadfred bbadfred Join Date: Mar 2008 Location: rantoul Il Posts: 461	Re: Won't start when hot! No matter what you do find get a mini starter anyway! You will never regret it!!

05-21-2012, 10:24 AM	#16
gcburdic Restoration Virgin! Join Date: Jan 2008 Location: Huntersville, NC Posts: 8,298	Re: Won't start when hot! check this thread for a mini starter that weighs just 7lbs and is $60...http://67-72chevytrucks.com/vboard/s...d.php?t=521843.....This will be the route I go next time I need tho change out the starter.....better than laying on my back trying to get that 20lb starter in place Let us know what works for ya!!! __________________ Geoff with a G 1968 Chevy C10 SWB The Mistress 1972 Custom Deluxe C20 Suburban A Suburban Named Isabella 1966 Ford Mustang Mama's High School Graduation Present

05-21-2012, 10:24 AM	#18
jchav62 1962 C-10 Join Date: Apr 2005 Location: Las Vegas, New Mexico Posts: 4,978	Re: Won't start when hot! The timing may just be a little too advanced. When I first saw your pic and saw the Edelbrock carb, I was going to blame it (heat soak) but after reading your post, I realized that's not your case. Also, like the other's said, check your positive cable from the start... and make sure the terminals are clean and tight. Good luck... JC62 __________________ Joseph Chavez "See the USA in a Chevrolet!!" ......................_____ .........________//__{\_____ ,,,,,,,/__(O)___//___/__(O)_/ 1962 C10 Shortbed Fleetside 327/th350 GV overdrive 1974 C10 Longbed Fleetside 350/th350 "The Trash Truck" 1999 Chevy 2500 OBS, Longbed 5.7/4L80E 4x4 2015 GMC Sierra SLE 1500 4x4

05-21-2012, 07:52 PM	#19
bowtiecharlie Registered User Join Date: Jan 2012 Location: quinton,nj Posts: 28	Re: Won't start when hot! I had a 72 short bed that would not "crank over when hot"! You could jump the starter with a screwdriver and it would start, but not with the key!! After weeks of new parts ,battery,starter,ns switch, ground wires to the frame and fire wall ,I found that the wire that runs from the Positive batt terminal to the fender (black junction block) was shot!! I cut and soldered a new wire terminal on it and it was good as new!! You should also have one from the Negitive cable to the fender direct,with no junction block!! __________________

05-21-2012, 08:43 PM	#20
fastwillie 696969 ~Rest In Peace~ Join Date: May 2005 Location: CALIFORNIA NOR CAL Posts: 9,707	Re: Won't start when hot! good thing its not a blower engine __________________ is it fast ? it has a lighting bolt donut? B___H please, I can remove 90% of your so called "beauty" with a kleenex

05-21-2012, 10:27 PM	#21
chevy72pu Registered User Join Date: Jan 2009 Location: Sandersville, GA Posts: 298	Re: Won't start when hot! The timing thing could be it. We advanced it to the limit and then backed it down a hair. I didn't mention this earlier, but it does "diesel" for a few seconds when you shut it off. I usually just ease out on the clutch to stop it. I'm not gonna change too many things at once so I can tell what corrects the problem. __________________ How 'Bout them Dawgs! '10 Traverse LTZ 03 Silverado Z71 ext cab 99 Yamaha Grizzly 600 72 C10 350/350 sportside bed. 68 C30 flatbed. 350 4-speed. "I've got a good memory, it's just short!"



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05-21-2012, 10:31 PM	#23
doubleb's69 Registered User Join Date: Aug 2010 Location: Des Moines, IA Posts: 1,241	Re: Won't start when hot! Nice looking engine bay. Is your lower radiator hose resting against your fuel line. If so that would really aid in the transfer of heat to your fuel and like LockDoc said it would boil while idleing. My truck would run fine once started as well but it would eventually just shut off with the factory cast iron intake and then I would have to let it sit and cool down to get it going again. I put a new aluminum intake on and put on a set of cross over block off intake gaskets on and it seems to be ok now. __________________ Bud

05-21-2012, 10:58 PM	#24
67ChevyRedneck Hittin E-Z Street on Mud Tires Join Date: Nov 2004 Location: Greenville, SC Posts: 23,090	Re: Won't start when hot! You need a solenoid heat shield. (the one below is just a generic search, but the GM one looks just like it... it may be the correct one...) http://shop.advanceautoparts.com/web...___#fragment-2 __________________ Jesse James 1967 C10 SWB Stepside: 350/700R4/3.73 1965 Ford Mustang: 289/T5-5spd/3.25 Trac-Loc 1968 Pontiac Firebird: Project Fire Chicken! 2015 Silverado Double Cab 5.3L Z71 2001 Jeep Wrangler Sport 4.0L 5spd 2020 Chevrolet Equinox Premium 2.0L Turbo 2011 Mustang V6 ~ Wife's ride American Born, Country by the Grace of God 1967 CST Shop Truck Rebuild! My 1967 C-10 Build Thread My Vintage Air A/C Install Project "On a Dime" Trying my hand at Home Renovation! 1965 Mustang Modifications!

08-03-2017, 10:43 AM	#25
CountofMonteCarlo84 Registered User Join Date: Jun 2015 Location: Longwood, FL Posts: 165	Re: Won't start when hot! I have had similar symptoms with a fuel pump going bad.

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