Fuel supply/vapour lock.

[ecurie_ecosse]

Hi everone, remind me about vapour locks in the fuel supply.
Things like what causes it,and where to start. /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif
Iknow,we've covered all this before.But I've forgotten. /bcforum/images/%%GRAEMLIN_URL%%/eek.gif


Stuart. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif

 

[sparkydave]

Hi Stuart, vapor lock means that the fuel pump is trying to pump vapor instead of liquid, or that the float bowl doesn't have liquid fuel in it. Just a few things that can cause it:

-Overheating inside the engine compartment
-Missing heat shield between exhaust and carburetor
-Metal fuel line rubbing against something hot
-Air leaks in fuel pump or fuel line

The last one happened to me, and was driving me up the wall even though I had put some insulation around the metal fuel lines and under the carburetor. Finally put a different fuel pump in, and voila, it worked again. If you get vapor lock, it might either stop abruptly, or just start losing power and finally dying in mid flight.

 

[Sarastro]

There's a fair amount in the archives about this. These cars are definitely prone to vapor locking, and, I suspect, modern fuels make the problem worse.

Here is what I ended up doing: https://www.nonlintec.com/sprite/fuel/