Vette stalls out when hot... ideas?
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,832
Likes: 0
From: Florida
Vette stalls out when hot... ideas?
The car starts fine and runs great, but say I shut it off and run into a store, come out and start it up.. it will start, but then it will idle down to nothing and stall out. After that it's really hard to get started again. Let it cool off and it will restart and run fine till it warms up again. If I'm at a light, I have to keep reving it so it won't die. Does anyone have any ideas of where I should trouble shoot first? BTW, it has a new fuel pump and once it's under way, has no trouble excelerating.
Le Mans Master
Joined: Nov 2001
Posts: 8,638
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From: LONG ISLAND
2025 C3 ('68-'73) of the Year Finalist - Unmodified
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Burning Brakes
Joined: Oct 2009
Posts: 1,065
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Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,832
Likes: 0
From: Florida
Burning Brakes
Joined: Jan 2007
Posts: 1,164
Likes: 1
From: Port Clinton Ohio
St. Jude Donor '08-'09-'10-'11-'12-'13
To me vapor lock is a bit of an urban legend. I've heard about it a million times but never seen it happen. The idea is that a fuel line is too close to something hot like exhaust. The cure is to re-route the line away from the heat.
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Racer
Joined: Jul 2010
Posts: 430
Likes: 31
From: Ontario
I've had actual vapor locks occur. It has to be pretty hot under the hood for it to happen though. i.e. I had a little Ford Ranger that I had dropped a built 302 in. The fuel line ran across the top of the engine and I was running an electric fan. The fan wasn't coming on soon enough and when it got too warm under there the fuel in the line would vaporize and the engine would die, typically in heavy traffic on a busy street. I rerouted the fuel line and modified the fan setting and presto.
Instructor
Joined: Apr 2004
Posts: 201
Likes: 1
From: Taunton Ma
HEI or points? I had a similar issue that after the car was hot and i came to a light it would slowly rev down until it stalled. Had to keep reving the motor. Replaced the HEI module and that took care of it. On mine if you put your hand on the top of the distributer it was pretty hot. I think that it was a result from who ever installed the distributer used the original resistive wire as power.
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,832
Likes: 0
From: Florida
I've had actual vapor locks occur. It has to be pretty hot under the hood for it to happen though. i.e. I had a little Ford Ranger that I had dropped a built 302 in. The fuel line ran across the top of the engine and I was running an electric fan. The fan wasn't coming on soon enough and when it got too warm under there the fuel in the line would vaporize and the engine would die, typically in heavy traffic on a busy street. I rerouted the fuel line and modified the fan setting and presto.
do you think 200 is to high? The Hei has given me problems in the past.. I replaced it a couple of years ago.. at that time the car just wouldn't start.
Last edited by Scudd; Sep 17, 2010 at 10:33 AM.
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
Mine is doing the same thing. What we learned is that the fuel is boiling in the carb after you shut it off, and the fuel is dumping into the carb and flooding. This is due to the fact that the heat is transfering from the intake into the carb in my case. I have no hood clearance so i cant insulate it at all. I am going to pull the intake and replace the gaskets with a propane engine style gasket. This has the metal heat riser block off in it. As well i am going to try to re-route the fuel line from the front of the engine to the side so it spends less time on top of the intake manifold.
Melting Slicks
Joined: May 2006
Posts: 2,590
Likes: 403
From: Nashville TN
St. Jude Donor '09
Previous owner had removed the return line on mine and I had problem with engine just quitting and not restarting until it cooled. I replaced the gas cap with a vented cap from AutoZone for $5-10 bucks and have never had another issue.
Racer
Joined: Jul 2010
Posts: 430
Likes: 31
From: Ontario
I just had the same carb boiling problem in another little Ranger pickup. That one has a 347 in it with an Edelbrock carb. I didn't put a heat insulator between the intake and carb and it wouldn't start hot. I carved an insulator out of the 3/4" plastic they use in hockey arenas for the boards and the problem went away. You can even use insulators made from wood if you're good with a scroll saw and you want to test the theory.
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
This is why i wish i would of stayed with the stock style QJ and intake. Less hassle and BS after wards with all this Edelbrock crap. It would of fit under the hood better,and wouldnt have this heating issue.
Instructor
Joined: Nov 2007
Posts: 108
Likes: 1
From: Easton CT
I had a problem with my 62, where on hot days if I left it for about 10 minutes, it would restart, but then stall in a minute or two and then would not start for another half hour or so. I suspected vapor lock in the fuel pump, and proved it by pouring cold water on the fuel pump right after it stalled. It then started right up. A new fuel pump fixed it permanently. It sounds like your problem is vapor lock in the carb. You can prove it by getting it into the stalled mode ouside your garage, and then running water from a hose over the carb bowl area and seeing if that allows it to start and run.
Drifting
Joined: May 2006
Posts: 1,480
Likes: 2
From: Circleville Ohio
Vader Vette
The car starts fine and runs great, but say I shut it off and run into a store, come out and start it up.. it will start, but then it will idle down to nothing and stall out. After that it's really hard to get started again. Let it cool off and it will restart and run fine till it warms up again. If I'm at a light, I have to keep reving it so it won't die. Does anyone have any ideas of where I should trouble shoot first? BTW, it has a new fuel pump and once it's under way, has no trouble excelerating.
Burning Brakes
Joined: Dec 2007
Posts: 889
Likes: 0
What have you done to it very recently? Or did it all of a sudden, all by its lonesome, start doing this? Contaminated gas? Clogged filter? Bad gasket in the carb? What kind of carb are you running? When was it last touched? Timing issue?
Thread Starter
Safety Car
Joined: Dec 2001
Posts: 4,832
Likes: 0
From: Florida
Ok.. I tried the cloths pin thing... loaded it up.. Still stalls out after it gets warmed up. The fuel filter is relativley new- less than 1k miles on it. Whats the gasket thing? BTW..it has a Edlebrock 650cfm carb.
