Lately whenever my car sits for over about 2 hours it gets hard to start. After I prime it with about a dozen pushes of the gas and start it it runs for a few seconds before slowly losing revs until it leans out and dies unless I really open the throttle, usually if I let it die and then crank again it starts normal. At first I thought it was vapor lock because I have always had problems with the qjet hot soaking, but after installing a clear fuel filter I now know that all the fuel is draining back down the lines into the tank. My question is: are our fuel senders supposed to have check valves in them? I dropped my tank and blew through it the wrong way and got no resistance so I didn't think it was supposed to. I've heard the check valves in the GM mechanical pumps are known to be wonky. Carb pump and all rubber fuel lines have been replaced and choke is properly adjusted (just barely cracked at 50-55deg). I am thinking of adding an electric fuel pump but I feel like having to prime itself every time might wear it out prematurely and this is my daily driver so can't have that. Should I try just adding a check valve near the tank? I feel like just adding another pump isn't really resolving the problem if it will still just drain back into the tank.
Hard start / fuel drain back
- Thread starter Bludacious
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I've had the same issue before and thought it was heat soak. Ended up finding my rubber lines from the sender to the metal frame line were rotted and sucking air, but wouldn't leak fuel. Replace those and see how it goes. Plus it'll only cost you a few bucks for couple of feet of some quality hose. Standard 3/8" fuel hose they sell now is junk. I only use fuel injection hose even on a low pressure mechanical pump system.
As I said, all rubber lines have been replaced with quality flexible FI hose about 2 weeks ago. People who ride with me say they still smell gas (I've gone nose blind to the fumes) so I'm going to go rubber the whole length and see if it gets any better. Since it is a rust belt car the metal lines that go over the muffler are already pretty crusty so there's a decent chance the ones that run under the body aren't in great shape either.
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