problem vapor locking need help

[imported_v12lincoln]

Hi everyone. I am having a major problem with my car vapor locking. it seems to do it at temps as low as 80 degrees. the engine is running at 165 degrees and I have an electric fuel pump installed running through the stock fuel pump in case it vapor locks but it still continues. I am waiting for my new water pumps from Skip. radiator has been redone and made with a new 4 core with as many fins as possible also an electric fan. carb has a 3/4 inch phenolic spacer. my next addition will be either a fuel cool can or remove the stock pump and use the electric with a return line to keep the fuel circulating.

anyone have any other ideas or remidies. Im in california and this new gas that is suppose to clean the air seems to vapor lock real quick.

Thanks.

Jack

[jrbartlett]

The electric fuel pump should be mounted as close to the fuel tank as possible. Also, make sure there is no restriction in your gas tank. Sounds to me as if your problem isn't necessarily the engine operating temperature. You might look for a hot spot in the fuel system (caused by proximity to exhaust) and insulate it. The presumed higher volatility of modern fuel is also worsened if there is a restriction in a fuel line or the fuel pickup on the suction side of the fuel pump. Make sure the fuel lines haven't been replaced with smaller-diameter lines, or smaller fittings. There is another approach -- mix a little diesel fuel into the gasoline, thus reducing its volatility. Finally, I'm assuming that you've confirmed that what you are describing as vapor lock is in fact a fuel problem. An ignition condensor or resistor that is breaking down under load and heat can sometimes mimic vapor lock.

[imported_v12lincoln]

when I restored the car I made sure the tank was boiled and sealed all the fuel line is new with no restrictions including the pickup tube. exhaust runs on the other side of the car so thats no problem. gas tank and fuel lines are cool until it gets to the fuel pump which at 165 engine temp the fuel pump is to hot to touch. checked the condensers and baked a new set to 200 degrees and they were still within tolorance. I think I will try the deisel fuel. california fuel is the oxgyonated crap. thanks for the help.

[imported_v12lincoln]

fixed the vapor lock issue. got rid of the stock pump and am running on the electric with a 3psi regulator, drove it for 2 hours in the heat witout a problem even after shutting it off and letting it sit for 20 minutes.

[Guest imported_V12Bill]

My 48 Lincoln has given me fits with vapor lock for years.I fhaave an electric fuel pump mounted near the tank. On Sunday I stalled at an intersection 2 blocks from home ( I forgot it was stick shift) , had to be hand pushed out of the middle of the street, and then spent 1/2 hour trying to start it with a 12 volt jumper battery (direct to starter), pouring cool water on the fuel pump and gas line to carb, and cranking some more. Finally after choking the carb to the point of almost flooding the engine, it started and ran fine.

This is not a new problem, but it seems to be getting worse. Jack, I don't see how bypassing the fuel pump solved your problem with VL. There are 2 check valves in the pump that should allow gas to pass through a "dead" pump with an electric pump pushing gas to it. What am I missing here? Does a quart of diesel fuel per tank help ?

Bill

[imported_v12lincoln]

havent tried the diesel fuel, my problem was the stock pump even with the electric pushing through it would get so hot even with normal operating temps that you could hear the fuel perking in the fuel pump, you could also take the fuel line off at the carb and get nothing but vapor. my underhood temps are running around 200 and it seems to not be venting the under hood heat. so far there has been no vapor lock just running the electric pump, havent been stuck in rush hour traffic yet in temps over 100, that will come soon when I drive it to hot august nights.