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cruiserman · 04-19-2009, 07:05 PM

The float is set at 0.375". I checked the fuel squirt from the acc pump, and it's not good. The pump is new and looks good. Check ball is in place. If I ramp up the throttle it sounds OK. If I blip it, it will gasp for air. If I blip it with the intake covered, it does better. Maybe something stuck in the fuel passage from the pump?

A few notes:
* Vacuum from the port on the front driver's side of the carb only produces 8". Intake vacuum is 16.5" at the dual port near the distributor.
* timing is 10*BTDC base. with vac it's 15*, so I'm thinking it needs more vacuum. if i use the intake port, timing jumps way up. probably need to use that source and turn down the adjustable vac advance to 15* or so.
* 73/43b primary jets/rods. stock is 72/43b.

04-19-2009, 07:05 PM	#8
cruiserman Registered User Join Date: Dec 2006 Location: Idaho Posts: 210	Re: Qjet accelerator pump The float is set at 0.375". I checked the fuel squirt from the acc pump, and it's not good. The pump is new and looks good. Check ball is in place. If I ramp up the throttle it sounds OK. If I blip it, it will gasp for air. If I blip it with the intake covered, it does better. Maybe something stuck in the fuel passage from the pump? A few notes: * Vacuum from the port on the front driver's side of the carb only produces 8". Intake vacuum is 16.5" at the dual port near the distributor. * timing is 10BTDC base. with vac it's 15, so I'm thinking it needs more vacuum. if i use the intake port, timing jumps way up. probably need to use that source and turn down the adjustable vac advance to 15* or so. * 73/43b primary jets/rods. stock is 72/43b. __________________ 72 C2500 LWB 402 Sierra Grande 05 Odyssey 08 Tundra Last edited by cruiserman; 04-19-2009 at 07:10 PM.