Vapor LOC
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
Drifting
Joined: Jun 2005
Posts: 1,950
Likes: 498
From: Chino Hills CA
Make sure it's really vapor lock that's causing your problem. Vapor lock is the boiling of fuel in the fuel lines, preventing the fuel pump from doing it's job since it's trying to pump vapor. If you let your car sit for 20 minutes and it starts right up, you may have vapor lock. If it doesn't start, your problem is elsewhere. It's interesting to note that fuels used to be refined with boiling points lower in the winter and higher in the summer to reduce the chance of vapor lock. With the advent of fuel injection and higher fuel pressures, modern cars no longer have this issue.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,594
Likes: 7,042
From: New Or-leens Loo-z-anna
I could actually hear the fuel boiling in my Edelbrock after driving in summer traffic once the engine was stopped.....then, no starting for 15-20 minutes.
The heat insulating spacer stopped the boiling.
I checked the fuel line on the frame by the passenger exhaust manifold before it entered the fuel pump with my infrared gun.........200*F after I turned the engine off!
The heat insulating spacer stopped the boiling.
I checked the fuel line on the frame by the passenger exhaust manifold before it entered the fuel pump with my infrared gun.........200*F after I turned the engine off!
Melting Slicks
Joined: Oct 2003
Posts: 2,187
Likes: 830
From: Chapel Hill NC
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As already stated you need to determine if the problem is in the carb or fuel lines. Weak fuel pump could cause problems in the lines. When problem occurs is there suction when you remove gas cap? It is my belief that todays gas is formulated for fuel injection and does not do well in carbs. Electric fuel pump or return lines to gas tank may be needed.
