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Vapor lock?

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Moose33

Moose33

Jedi Hopeful
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is there such a thing as vapor lock when it comes to fuel pumps? I've got a facet aftermarket pump and after about 20 minutes at idle it stopped pumping fuel.

I removed it from the car, blew out the lines, and bench tested the unit and it turned on but wouldn't push anything out. I put some compressed air through it (the unit) and blew out the fuel then tested it again and all was okay.

any thoughts before I put it back on the car? I know the tank is clean, I just recently got it back and the lines have been cleaned/replaced as well.

fuel and paint are the last two things keeping me off the road. thanks to all in advance!
 
Don't think so. Gas has to boil to cause vapor lock check this https://www.aolsvc.worldbook.aol.com/wb/Article?id=ar581040&sc=-1 and it can't boil down in the fuel pump.
I would guess it is an issue with the pump itself. Possibly a loose internal connection or something caused it to stick.
I tried an aftermarket pump once and it quit after a week so I put the original back in. I still have it in there after 24 years I have owned the car with the ocasional maintance of points condensor etc. I replace the diaphram once after it got too stiff to work well.
I took the aftermarket pump apart (which meant going into a case that was pressed together and not meant to be repaired) and found a loose connection at the ground wire inside. It worked ok then but I tossed it rather than depend on it out somewhere. Also when it was first working ok it would not stop while in the car even after the pressure came up.
Bob
 
True, it won't necessarily boil in the fuel pump, especially if it's electric. I'm having a similar problem right now with my mechanical pump where it basically gets a big air pocket in the line leading up to the pump, so I'm working on cleaning the crud out of the fuel tank, replacing the rusty fuel lines, and making sure I don't have any air leaks in the rubber hose fittings. I'm also going to look and make sure the pump is doing its job like being able to suck the fuel up from the gas tank. Granted, my mechanical pump still gets a mite warm being bolted to the engine block, but this wasn't a problem until recently. If the electric pump was running but not pumping, it may have been that the flap valves had something caught in them.

-Dave
 
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