northiam

Help I have a 750 DP HP on performer manifold spitting fuel out the booster jets when the engine is hot and turned off. I have installed a 1/2" heat spacer, insulated the fuel line, lowered the float levels 3mm lower than the IO, which has delayed the problem but after a few hours running it happens again!!! The fuel pump pressure can get up to 7 psig. max. Any ideas

pracy

do you have a fuel regulator? shouldn't need one for 7psi but i am not totally sure about that...

davis

The most common problem for this condition is a stuck or floating needle. Check to ensure that you don't have some material entering the carburetor float bowls from the tank. Ensure that you have a fuel filter and that no debris is traversing the filter to stick up the needle or its seat.

It is possible that the springs and/or seats (probably rubber tip on the needle) are in need of replacement. Another possiblity is a leaking float. Check to see if your floats are air tight. Pull them out and rattle them to see if they have fluid inside of them. If the fuel is coming from both primary and secondaries, then check them both otherwise, just check the side that is bleeding fuel.

:davis:

STROKEXD

Had this problem recurring over many years. It only got fixed for good with a regulator, heat insulator and heavy duty needle and seats (Holley P/N 6-521 Needle and Seat Assembly w/Titanium Needle - .150)

7psi would be too much for standard needle and seats.

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northiam

I have seemed to resolved the prob by installing a fuel cut off solenoid valve just before the carbie. I switch off the fuel 20 seconds before turning it off! Acts as a thief deterrent too! This allows the fuel level to drop in the primary bowl and relieve pressure off the needle seats. Ive removed the phenolic spacer as it fits the shaker better. I ve also dropped the fuel levels 6mm under the IO. Do yous thing the lower levels will be OK?

STROKEXD

As long as your mixtures are not too lean (lowering float will lean it slightly) and it doesn't run out of fuel at WOT it makes no other difference.

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TruBlu351

I was suprised by a new stock mechanical pump giving me 9psi @ idle. Worked OK though.........until the electric one get fitted.

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XE Falcon
393 Tremec TKO 9"