4150 carb issues

[Ames]

I am having a problem with the accelerator pump on my Holley. the car had sat for a long time (30 years) and the accelerator housing had warped. We tried to level it which made the screws to long and I stripped one of the threads in fuel bowl so that it won't tighten completely and I have a small leak. It leaks when I press the gas not at idle. Two questions, can I get the fuel bowl and the accelerator housing new? and, has anyone had luck putting a new set of threads in the fuel bowl?

 

[Ford5of5]

Holley carbs are standardized. You can definitely get the specific parts from Summit Racing. You could also buy a used Holley and salvage the parts from it. You could re-tap the screw holes but in my opinion its really not worth the trouble. Aluminum is a soft metal and will require a new, sharp tap and you should use a good cutting oil. Only do half turns of the tap and then reverse to cut the chip. Aluminum is easier to screw up than steel. Pun intended!

If the accelerator pump housing has warped due to age then just replace the carb. The brass and aluminum break down over the decades. A new carb may do wonders to wake up the car.

 

[Ames]

Thanks 5, not what I wanted to hear but what I expected to hear. I'm going to have my machine guy look at it and get his thoughts. I appreciate your advice.

 

[Ford5of5]

Did you remove material to get the pump cover to sit flat? I don't know one way or the other but wouldn't that decrease the amount of travel of the pump, thus decreasing the shot of gas?

 

[Ames]

I did not think of that because we did remove a substantial amount of material considering what we were working with. The more I run it now the worse it leaks, now around both bowls and the accelerator. So, I took your advice along with several others and purchased a new Holley. I will update next week when it comes in.

 

[Ford5of5]

Is it possible that you or someone else tightened the screws too much? I warped a Q-jet once and my brother John is famous for cracking carb base plates by tightening them too much. Aluminum will not take the same kind of gorilla abuse that steel engine blocks can withstand.

 

[Ames]

I did, the screws ended up being too long after the we machined the housing, I bottomed one screw and then stripped it. I researched some options like, oversized screws, new threads, universal fuel bowls. But in the end, advice I got was that this would be a a bandaid for this carb and if the bowls are deteriorating then the body probably has too.

 

[Ford5of5]

Ya, I've learned the hard way that torque specs matter, even more so with aluminum. Without hyperbole, I've replaced the oil pan gasket 4 times on a Pontiac 400; for some odd reason the gaskets would squeeze their way out from under the flange. 15 lbs of torque means 15 lbs of torque! I knew it had to be something I was doing wrong.

 

[Machoneking]

I could of fixed it for you before you ran the screws in the bowl. Anyway, at this point you can replace just the bowl section with a parts carb. Unless your determined to buy a new carb.