major carb problem please help

HemiChallenger · 05-02-2005, 07:47 PM

I can't figure out what the f$!k is wrong with the carb on my truck. Once I adjusted the valves the thing had a bad bad stumble, the accelrator pumps were way to heavy and sprayed fuel as soon as you tapped or bumped the throttle. So I tightened up the springs, and still to no avail when the accellrators kicked in bad bad bad stumble. So I adjusted the floats, same problem only worse now with the floats adjusted properly. The thing has backfired about 50 times now and wont even fucking run, I adjsuted the floats all the way down and still to much fuel and it just dies out weather I have the fuel pump turned on or off (I have a manual switch). WTF is wrong I almsot killed the truck and myself I was so pissed off, any input would be appreciated. Oh and this is a NEW holley 750 double pumper, thing ran fine when I bought it not now.

Strtracer · 05-02-2005, 08:04 PM

If you are getting fuel spillage with the floats all the way down, you either have to much fuel pressure, or something stuck in the needle seat(very common on holleys). Pull the needle seat assembly out and check.

HemiChallenger · 05-02-2005, 08:08 PM

Not sure what that would be, pull the bowls off and in the metering block somewhere?

HemiChallenger · 05-02-2005, 08:36 PM

Well read holley's site and it awnsered my questions on all the adjustments of the carb. My float needles may be stuck because I dont get any movement out of my primary bowl, and the secondary I can see move just fine. When I pulled the screws to set the float levels yesterday I had fuel visible today I did not. I guess I'm going to have to replace all my plugs and start over huh?

Holley says fuel should spray when the throttle barley moves and a stumble is a lean condition, but there's no damn way! thing smokes like a fucking bitch! thick black shit like a diesel. WTF gives I guess start over and play fuck around with my carb, I remember why I hate Holley's now.

HemiChallenger · 05-02-2005, 08:39 PM

One more question, should fuel squirt out all over when you loosen the float level adjusters while the vehicle is running and the fuel pump is on?

**BigWheelinBubba** · 05-02-2005, 08:50 PM

Sounds like needle/seat or power valves blown out.

Strtracer · 05-02-2005, 08:59 PM

Yes fuel will spray if the pump is on. Youre running an electeic pump, do you have a regulator, and what is it set at. Max fuel pressure for a carb needle and seat is 6.5-7 psi, anymore than that and youll over fill the bowls and fuel will spill into the engine. Fuel level should be set pump on, motor off, and the fuel should be right at the bottom of the inspection hole, so it just trickles out when the car is runnning.

HemiChallenger · 05-02-2005, 09:16 PM

Ok, thanks for the info the pressure is set at 6 psi.