Hello James and Ole Truckers, Check gravity flow from fuel line by disconnecting it from the intake side of the fuel pump. Fuel should flow in a stream the size of the fuel line. If it doesn't, it could be one of the following is clogged: fuel line, fuel filter, fuel tank outlet, or fuel tank air vent.
If fuel does flow well, check flow from fuel pump when starter motor turns engine over and activates fuel pump. (This can be an explosion waiting to happen: get good advice on how to be as safe as possible.) If fuel pump pumps well, check carburetor. If all these function, you should see/smell fuel in carburetor with air cleaner removed when throttle is activated. (And, with strong spark, proper timing, and compression, she ought to fire up.) When you back flushed with air, was it with a bicycle tire pump? I think if you are losing vacuum in a fuel line, you will see fuel leaking out: is that the case? Hope this helps, Culver Adams 1952 Chevy 1/2 Ton PU Minneapolis, MN --- -----Original Message----- From: JZ <zorn...@sbcglobal.net> To: Old_ChevroletGMCTrucks moderator <old-chevy-truck@yahoogroups.com> Sent: Fri, Sep 6, 2013 12:02 pm Subject: [old-chevy-truck] No gas to carb My 235 had some problems with old gas which I believe I fixed by cleaning out the lines with forced air, dumping the old gas and flushing the tank twice and changing the fuel filter. I noticed that when back flushing the tank with air, gas came back up the pickup fuel line telling me the tank was tight. I am thinking I am leaking vacuum in the gas lines themselves. Should I replace them? That would be a pain. Could that be the cause because I have run out of other ideas. How would I test that? James Zorn zorn...@sbcglobal.net