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It's been awhile since I've been on here ... still have my '80 Sunbird and my '76 Astre ... my question is about the Astre ... what carb does the '76 140 inch have? Holley 5200? I think that's what it is. Anyway, it will not hold it's prime ... if I crank it long enough to get some fuel to pump up then it will start ... but the battery usually gives out before that ever happens ... I've been priming it myself to start it. Once started,it will start all day ... until it sits overnight ... then it loses its prime again. Soooooo ... why is it losing its prime? Should I rebuild the carb? Get a remanufactured one? Also ... what is the best choke to use on these carbs? Mine just has the water activated choke with no electric function at all ... don't like that choke setup very much. Lots of questions I know ... sorry ... any info is greatly appreciated!!! Thanks!!!

I am not familiar with the Holley 5200 but I know Quadrajets have a similar problem because there are some plugs on the bottom of the float bowls that leak. They will slowly drain the fuel from the bowls into the intake and are dry on startup. The usual fix is to either replug them and or epoxy them so they don't leak. You may have a issue with the floats as well but I would think a tear down would be best to see what's going on in there. Here is a pic of a 5200 for ID purposes.

You may have a fuel pump problem. The fuel pump may be allowing fuel to seep past it when not in use so the fuel line will have nothing in it when you go to start the engine. You have to crank the engine to get the oil pressure switch to engage, which enables the fuel pump.

A quick test would be to bypass the oil pressure switch and listen to see how long it takes for fuel pressure to build. Initially the fuel pump will run fast when pushing fuel, but when it reaches pressure, it sounds like it is bogging down.

My 76 Vega fuel pump has a little bit of seepage, but it doesn't go too far overnight and usually gets pressure after a second or two.

Ken

Does that carb use in in-carb filter like the Varijet and Q jets? Could be as simple as someone left out the one way check valve (plunger) that fits inside the filter.

Does that carb use in in-carb filter like the Varijet and Q jets? Could be as simple as someone left out the one way check valve (plunger) that fits inside the filter.

Carb for 76 Astre:

Filter with valve :

Doug in P.R.