Vapor Lock or not????
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Joined: Dec 2003
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From: Blythewood S.C.
St. Jude Donor '14
Vapor Lock or not????
Ok guys, I have a '78, L82, 4sp stock with 66k miles on it. When the engine gets to normal running temperature and after cutting it off for a few minutes like when getting gas, the engine will just barely crank over and of course will not start.(acts just like a dead battery) It does this a lot of the time. If I let it sit for a while to let it cool down some, most of the time the engine will crank over fast and starts and runs fine. I'm thinking maybe the dreaded VAPOR LOCK is causing it, but what is puzzling me is why will vapor lock cause the engine to just barely crank over???? Also, at times when it does this, I have used jumper cables to boost the battery and it cranks over fast and runs fine until next time. The dash voltage meter reads close to 14 volts all the time when driving as if the battery is being charged ok. I did install a new fuel pump a few months ago and that made no difference. I have not insulated the fuel lines and really do not want to install an electric fuel pump. Can anyone explain to me how vapor lock will cause the engine to just barely crank over????Does this sound like vapor lock to ya'll 
and what remedies have some of you used to fix the vapor lock problem??? Thanks
and what remedies have some of you used to fix the vapor lock problem??? Thanks
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Joined: May 2006
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vapor lock does not cause your symptoms you have an electrical issue. Check all battery connections both at the battery, the ground on the frame and the starter. What is your initial timing set for? How old is the battery? Do you have a heat shield on the starter solenoid?
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Joined: Mar 2014
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I would be willing to bet it's the starter.
Starter gets hot it drags. Kinda common on Chevys.
Like said vapor lock will not effect the way it cranks, it just won't start.
Have the battery tested, if it passes, you can do a voltage drop test on the battery cables, but it's almost for sure a starter.
Starter gets hot it drags. Kinda common on Chevys.
Like said vapor lock will not effect the way it cranks, it just won't start.
Have the battery tested, if it passes, you can do a voltage drop test on the battery cables, but it's almost for sure a starter.
