The Stovebolt Site Forums The Shop Area Engine Shop Stripped carburetor screw

I’m in the process of of putting the stock intake manifold back on
Was putting the jet that was in the carburetor before but when I was putting the screws back in one would not snug down.
Should I try to re tap it or find a larger screw??
Thanks for ideas and tips

What make of carburetor and which screw? There may be another fix for it...

Manuel choke Rochester it’s one of the top screws of carburetor

I believe those screws are an oddball size- - - - -maybe a 12-something? Measure the diameter and pitch of the thread, and check to see if there's a Heli-Coil available for it. If so, you might consider modifying all the threads. If they're 10-32, I'm pretty sure Heli-Coil makes that size thread insert.
Jerry

Try a slightly longer screw. There may be enough threads deeper left on the bottom to grip.

If the threads don’t need to be sealed, try using a very thin piece of (al or cu) wire, possibly from a very fine stranded electrical cable, and insert it into the hole before inserting the screw (bolt).

Mikr

Looking into all options thanks.

I can't remember what size those screws are. Jon (carbking) probably knows. You could use J.B. Weld to hold a slightly smaller screw in the hole and then use a nut on it. Heli-Coil does make a 10-32 size. There is also a product known as Thread-Restorer (think Loctite makes it). I've had luck with that if the screw doesn't need to be too tight. What year and size of engine?

Engine is a 1957 passenger car 235 in my 52 Chevy truck

Rochester used at least 2 different threads depending on the year.

If the carburetor still has a tag, one could look up the original part number, go to the bin, pick up a screw, and measure the thread.

OR

One could take one's micrometer and pitch gauge, and measure the screw one has.

A micrometer and a thread pitch gauge are two tools no enthusiast of older vehicles should be without.

As far as what to do; my first reaction was: its a Rochester B, why bother?????

But to promote information, in the past we have on various carburetors worth saving:

(1) Used a heli-coil where there is sufficient "meat" in the area to rethread (MSC has the 10x32 Heli-coil kit for $72., how many threads are you going to repair). I can happily report I no longer have a single Rochester B to examine to determine if sufficient material to hold the Heli-coil They have ALL left the building!
(2) Rethreaded the hole to the next larger diameter with the same thread pitch, and made a new screw on the lathe, if we didn't have one. This I would consider ONLY if no Heli-coil were available. And the customer would be notified before hand, and given the opportunity to say no.
(3) A home enthusiast MIGHT get by temporarily with a longer screw of the same thread/pitch, but not a repair we could, or would, use in the shop.

And while it is certainly possible for an original screw to gall, and strip out the zinc alloy; there are number of vendors selling "dress-up screw kits" which use stainless screws. Stainless screws should NEVER be used on zinc alloy, unless one enjoys repairing stripped holes the next time the unit comes apart. Not throwing this at the OP, simply imparting information.

And just for the record, we have tested every epoxy sold by all local FLAPS, as well as tested the miraculous pot metal welding rods (I knew better than to try this myself, as I know, and respect, my welding limitations; we had a professional do the testing). We were not satisfied with any of the above for a professional repair, although an enthusiast MIGHT use one of the epoxies as a temporary repair. I don't consider the pot metal rods even suitable for temporary (at least on carburetors).

In this case, if the OP is really in love with the B, I would suggest just finding another exact replacement body. The B's simply are not that expensive. It took me 25 years to get rid of all of ours.

Jon.

With no more torque than a carb top bolt needs you could get by with an epoxy and a STUD. Never had any luck with glued bolts but studs are not removed so the set usually lasts. Have stud and carb body operating room clean before applying epoxy. I like Marine Tex for just about everything but JB Weld or Panel Bond also works. Do a test run on the nut on the stud before threading into carb; you want zero drag and then double nut stud to screw in. As with others, I've spent more time with a "how to" description than a Rottenchester is worth.