Carb question
 

i have a holley 750 4bbl double pumper on my stang. I recently noticed that only two of the 4 bbl were working. I was wondering if anyone knows why this owuld happen, and if ican take the carb apart and fix this, or is it just time to get a new one? Thanks for the help

Re: Carb question
 

Is it a vacuum secondaries? Either your vacuum line is unplugged or busted somewhere or the diaphram is busted. If its mechanical secondaries, you need to look at the linkage. How old is this carburetor?

Re: Carb question
 

are you looking at it in Idle or Wide open throttle. The secondaries only kick on at full throttle.

Re: Carb question
 

How do you know the other two aren't working??

Re: Carb question
 

I wondered the same thing.

Re: Carb question
 

If it's a double pumper then it can't be vacuum secondary.

Re: Carb question
 

i ntoiced it wasnt working when i was under the hood using the throttle to give it gas, and the two wouldnt open no matter how much gas i gave it or how long i gave it gas.

Re: Carb question
 

Are you sure it's a double pumper because it sounds as if you have vacuum secondaries in which case, you won't see them open because the engine isn't under load when it's out of gear.
The secondaries only open as the demand for fuel increases if, indeed, you do have vacuum secondaries.
If you have machanical secondaries and they aren't opening then I would say you have a linkage problem.
What is the model # of the carb. you're running? This will verify what kind of secondaries you actually have.

Re: Carb question
 

Sounds like you have a 3310 to me. Try what 82 GT suggested, and post the List #, found on the airhorn (choke tower). If it's 3310, then you've got a vacuum secondary 750, and it's operating normally.