Motor Stalling, Carb ???

[Nubbs]

When I drop the throttle after running full throttle my motor stalls. What's the cause of this and what can I do to fix it? Would a dashpot work? It kind of sucks to be going full throttle and then have the motor die and lose steering while at a good speed.
Thanks
Nubbs

[Blown 472]

floats too high and flooding?? you can try turning the idle screws out a turn or two more as this might help curb the lean conditon when you slam the throttle shut.

[Hotcrusader76]

What type of carburetor is it?
If it's a Holley what type of accelerator pumps do you have?
Do you think it's a lean or rich bog/stall?

[Nubbs]

It's an 800 cfm 4 bbl dbl pump w/ mechanical secondaries. I haven't changed the accelerator pumps, so I assume they're stock. I don't know if it's lean or rich.
Thanks

[Blown 472]

So you are saying it dies when you close the throttle?? or open it?

[Nubbs]

It stalls when I close the throttle. When I'm going fast at full throttle and high rpm, the motor dies when I completely let off the throttle.

[Blown 472]

Like I said, try turning the idle screws out one turn if it gets better give it some more.
I used to have that problem on my 413 in my car.
Do you have the plastic vents for the float bowls?? if so try taking those out too and see what it does.
[ August 20, 2003, 10:55 AM: Message edited by: Blown 472 ]

[Moneypitt]

When you restart the motor does it blow black smoke out the headers? If so you were rich when it died. You MAY be over flowing the secondary vent tube into the secondaries due to slowing the boat rapidly. If you want to check this, put a piece of fuel hose in an arc from the rear vent to the front vent and cut a half moon slot at the highest point. This should prevent flooding due to slopping fuel out of the vents. Are you idling on the idle circuit, or are the butterflys slightly open? The dashpot idea would work, but shouldn't be necessary if everything else is right......Moneypitt