Holley Dissection Inspection...

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Backfoot100

Full Access Member
Joined
Aug 18, 2017
Posts
374
Reaction score
648
Location
Florida
First Name
Eddie
Truck Year
1986
Truck Model
C1500 Suburban
Engine Size
Carbed 350
Accelerator pump adjustment would be my first look.
The pump arm is attached to the throttle shaft. The slightest movement of the throttle should shoot some gas through the pump nozzles in the throat of the carb.

The arm of the pump should not have any slack in it. It needs to be just snug against the pump diaphragm. Its adjusted with a small nut on the pump arm. That usually takes care of it.
Also the proper timing does indeed make a difference.

Glad to hear you're making progress anyway. May even make you a Holley lover yet..LOL.
 

Doppleganger

Full Access Member
Joined
May 24, 2019
Posts
12,816
Reaction score
59,450
Location
OH-MI: Just like it sounds
First Name
Chris
Truck Year
1985
Truck Model
K20
Engine Size
5.7
Buddy came by with his Snap On timing light. He watched the mark and I turned the distributor. He says it was at almost 50 degrees advanced...which might explain my backfires. o_O Dialed it back to 10 and took it for a spin. Does a slight backfire still if you get on it hard about 1/4 the time. Otherwise, its smooth and has decent acceleration, so still better than it was. The accelerator pump looks to be set and working pretty good, however I suspect I may have a slight vac leak somewhere. My idle is still a tad high and if I spray carb cleaner on the sides of the back section, the idle will fluctuate. Might be in the intake or at the base plate too - dunno. This motor only has 100k on it but was so cobbled when the PO pulled the Q-Jet and vac lines all off its a mess how anything is hooked up.

Its not 100% but very usable now. I have 2 cars I need to finish and make go away - if I have time I'll continue to probe into this, otherwise I'm going to use it when I need to and plan for the TBI/4L80e sway next year.

But its getting there.
 

Latest posts

Forum statistics

Threads
44,416
Posts
957,113
Members
36,752
Latest member
78 squarebody
Top