fouled plugs

[44070dart]

440... 750 holley...plugs j12yc are black in very short time and car pops back when given gas if idled too long....dont know jet size... no black smoke from exhaust at anytime..drive car in 1st or 2nd gear for 5 min. clears out popping and car runs ok...if jets need to be changed how to....or where else do I look

[MoparMarcIdaho]

but I would sooner think power valve.both a located in the metering block,the part right behind the front float bowl.

[mtrv8n]

could also be

1) float stuck or set too high

2) leaking internal gasket

3) accelerator pump leaking


I've had the last two happen on my Holley's. Mostly because of NYS fuel additives like MBTE and methanol. I now run an Edelbrock because it won't leak where it counts from those fuels.

[MoparMarcIdaho]

Cost/Wallet.Performer=better mileage(usually)less hands on,playin around.Holley=design flaws(old style power valves rupture at first backfire),no metering rods,like to leak,not too good on gas,but when they work right,will pull better through the traps and win more races.My thoughts,get an AFB or AVS for the street and run the holley on race day for best power output.

[Tarrbabe]

Try new gaskets and power valve. Reset float level and you should be okay.

[mtrv8n]

Basically, get a rebuild kit or send it to FBO for a rebuild.

I have a correction, my Edelbrock IS leaking..and I think it's the accelerator pump that's doing it.

it could also be damaged from heat...but, I'm springing for a new carb at this point.