Holley carb wont hold adjustment

[timberice]

I been trying to adjust a holley 650 carb for about a week. It adjust to the point were it seem to work good them the next morning its hard to start again. I had a friend take a look at it. He had it running good that day but then the next day it was back to the same thing. The carb is on a 305 and was on the car when i got it. I try to adjust the choke but thats not much help. I never had this many problems adjusting a eldelbrock carb. Any tips or help? Im almost ready to pull this carb and get a edelbrock unit.

 

[GhettoRacingKid]

Is your timing stable?

what are you adjusting?

did you check for vacuum leaks?

 

[pontiacgp]

what's the model number of the carb?

 

[gbondo57]

Not much has been stated about the engine setup at this point. But, if the 305 is fairly stock, that carb is big for it. We bought a 305 Elco with a decent cam, stock exhaust, torker II, and a 750 edelbrock. It was hard starting. We went to a 600 eddy and it started alot easier. Carbs need a proper vacuum signal. If the carb is too big, hard starting is a common symptom. If it surges when cold, then clears up, there is a vacuum leak that seals off when warm. Often an "old" intake gasket. :|

 

[online170]

. But, if the 305 is fairly stock, that carb is big for it.:|

No its not.

I sold a holley 650, 4150 series double pumper, to a freind with a 305 trans am, and tuned it for him. Bone stock engine just rebuilt. Runs great, starts good, no choke.

 

[DRIVEN]

Still not sure what you are trying to adjust. Choke? Idle mixture?

 

[Clone TIE Pilot]

Vacuum leaks will make a carb not hold adjustment. Also aftermarket carbs are known not to hold adjustments as well as factory Qjets.

 

[timberice]

Carb is a Holley 8150-5 with a electric choke. The engine is a stock 305. It has a aftermarket edelbroke intake. I tried to adjust the choke and car dosnt seem to respond well to it. My buddy thinks the electric choke is the problem. I crank the car is the point where the battery is loosing power then the car will start.

 

[DRIVEN]

If it's properly adjusted all you should need to do is pump the pedal once to set the choke and hit the key. They are usually very close from the factory. Check with Holley's tech support. Are you sure you don't have a vacuum leak or something? How does it run once it's warmed up? In my experience carbs don't go "out of adjustment" -- they just aren't tuned properly to begin with.

 

[gbondo57]

To disable this choke, loosen the 3 clamp screws on the black round housing, turn it clockwise, till the throttle sets all the way down. disconnect any wire. That should give you a no-choke setup.