Inliners International Forums General Discussion Engines Vapor Locking

I have a 66 Chev p/u with a new 250. The motor idles and runs good, but after 50 or so miles of continuous driving I have a vapor
lock problem. Any ideas?

Get a vented gas cap?

50 miles on the freeway,or street driving?

MBHD

It was freeway driving. We took the cap off and it made no difference. We're running headers with no heat source to the intake, but it's mid 70's to 80, here in Texas.

If you are sure it's vapor lock, you might try a heat shield between the exhaust and the fuel line.

Insulating wrap on the line between the fuel pump and the carb could help, as well as an insulator under the carb might help too.

More detail as to what exactly it's doing would help us if the advice so far isn't helpful.

Just a stab in the dark, fuel pump going bad,plugged fuel filter, float adjustment off.

How to tell w/little info to go off of.


MBHD

Just a thought: Steady driving under certain conditions can cause the carb to ice up. Long shot.

Ron

When the engine stalls, coast to a safe spot and take the air cleaner off. Is there ice in the venturi? If it's humid might be more of a possability. Feel the outside of the carb, it might be colder than you think. With the engine still off check for fuel by opening the throttle & (safety first!) check for accererator pump spray. Get a vacuum gauge, you can test the pumps ability to pull fuel from the tank & for restriction from the pump back in two simple steps.