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Fuel supply/vapour lock.

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ecurie_ecosse

ecurie_ecosse

Luke Skywalker
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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
 
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.
 
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/
 
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