carb problems

[Tom K.]

i had my holley 2818 rebuilt last year for a total restoration. after installation it ran fine during testing and tuning. now though it floods after about 30 seconds. replaced the needle valve and power valve along with new gaskets and o-rings. any help with what i should be looking for will be appreciated.

[Bill I.]

Re: carb problems

Tom, that's just about how long it would take for both fuel bowls to overfill.
Have you checked both float levels? Bill

[Joe C.]

Re: carb problems

i had my holley 2818 rebuilt last year for a total restoration. after installation it ran fine during testing and tuning. now though it floods after about 30 seconds. replaced the needle valve and power valve along with new gaskets and o-rings. any help with what i should be looking for will be appreciated.

Have a fire extinguisher handy, start the engine COLD, have rags stuffed below the sight plugs to absorb any spilled fuel and remove the bowl plugs, one at a time and adjust the floats........first the primary and then the secondary. You should adjust the floats until you have only a slight dribble of fuel out the sight plugs with a running engine. If you cannot stop the flow of fuel THEN:

Remove both float bowls and balance tube. Check both needle valves for debris or damage. It is possible, however improbable that the rebuilder used neoprene rubber needle valves. If they look swollen/distorted then replace both needle/seat assemblies with viton units, which will stand up to ethanol laced fuel. Check that either or both brass floats are not punctured/cracked and filling with fuel. If the problem is not here, THEN:

Check your fuel pressure. In the unlikely event that it is higher than (about) 8-9 psig, the needle/seats will not seal against such high pressure. Nominal fuel pressure should be (about) 4-7 psig.

[Tom K.]

Re: carb problems

thanks guys, i'll give those a try tomorrow