holley troubles

[RedRocket]

Every Holley I've ever had , on every vehicle and other people I know have had the problem of flooding when you shut off a hot engine. I've had heat sheilds, my boat is an open engine that runs cool at 160, and apparantly the fuel boils out of the bowls and floods the engine while washing all the oil off the cylinders for start-up. I haven't tried an insulator under the carb yet. What's with this, hard starting's bad enough but it's also wearing out my engine. MY new Demon better not do it!list of every holley'd vehicle I've dealt with that does it:383 stroker jet boat, 327 'vette, small block 'cuda, 72 vette w/zz502 crate engine. Feed back PLEASE!

[riverbound]

My boat was doing that I had a 750 w/ vacum secondaries and changed it to a 700dp and the problem went away.

[78Eliminator]

Set those floats low. When the needle/seat valve wears, the level rises and sneaks up on you. I have noticed that with Holley, you practically have to bottom out the adjusters just to get them to a decent level, which often rusults in you having to disassemble the bowls, and bend the floats to gain more adjustablility. Anyway, check those float levels!
J

[bigkatboat]

Your power valves are open at idle, not enough vacuum to keep them closed. When you are cranking (hot), very low vacuum, it is flooding because the power valve (s) are open. You crack open the throttle (just a 'bit') and it fires up and blows black smoke, right?

[RedRocket]

I'll check my float levels. what exactly does the power valve do? I've tried all different starting techniques. the only thng that works sometimes, (1out of 10) is to not touch the gas and it firesonce real quick, if it doesn't start then it turns over for 5 seconds. there probably is black smoke cuz it is flooding.

[Maxey]

Hope this helps:
Remove the brass screw at the side of the bowl.
With the engine @ idle, adjust the float level so that fuel will "just spill over the lower edge of the opening.
Be cautious.
The power valve will be open @ cranking speed because of low vacuum, but the power valve feeds fuel into the main circuit, and that discharges at the nozzle in the venturi area. There is no vacuum there at idle speed. If fuel is spilling off of the nozzles in the venturi area, the fuel level is not being controlled by the float system.
Causes: Heavy float, neele and seat deffective, out of adjjustment/binding, dirt, etc. holding needle-valve open.

[Maxey]

Hope this helps:
Remove the brass screw at the side of the bowl.
With the engine @ idle, adjust the float level so that fuel will "just spill over the lower edge of the opening.
Be cautious.
The power valve will be open @ cranking speed because of low vacuum, but the power valve feeds fuel into the main circuit, and that discharges at the nozzle in the venturi area. There is no vacuum there at idle speed. If fuel is spilling off of the nozzles in the venturi area, the fuel level is not being controlled by the float system.
Causes: Heavy float, neele and seat deffective, out of adjjustment/binding, dirt, etc. holding needle-valve open.
One last thought, if you have an enclosed engine, and the temps are very high, the fuel might be boiling and entering the engine from the internal vents (inside the airhorn). Does your carburetor have "J-tube" vents? :cool: