the carb on my car i noticed was leaking so when i went to tighten it the damn thing fell of. the previous owner had but jb weld or expoxy to hold it in :af: its stripped so i need to rethread it. it has the smaller inlet so i wanted to tap it for the larger one. there is enough metal there to do it. where can i get the tap for that or do they make a repair kit for it thankk
There is a thread on this very thing, but I couldn't seem to find it. You might have more luck searching than I did. Don't touch it until a few more people comment on this - there is a good fix out there. Sorry I can't be of more help.
When I had this problem several years ago there was a repair part available which had a slightly larger OD and self-cutting threads. I've also seen another version with a compression fitting. Try Napa. John :beer
I had the same problem on my Rochester 2GV. I tried using the self-tapping fuel-inlet gizmo - the picture shows a standard fuel-inlet fitting alongside the NAPA self-tapping version. The result? The tap was poorly made and did a very poor job of cutting threads, especially into the clean portion behind the original threads. It made such a mess I had to find a replacement airhorn for the carb. If you try the self-tapping route, check to make sure the cutting slots have sharp edges. Use a thin file to sharpen them and angle the slots in the cutting direction. I would even cut four more slots to get better cutting and cleaning action. Use a hacksaw to cut the slots and a file to sharpen them. It's best if the airhorn is removed so you can cut the threads on a bench and clean the shavings out when done. The other 'fix' offered by NAPA is a fitting with two o-rings. It also replaces the original fitting and expands inside to seal the o-rings. However, there's no place for the fuel filter, so you to buy an in-line filter and cut the fuel line somewhere to install it. Third choice is to find a carb shop that has the proper, really big, fine-thread tap and Heli-Coil plus the jig to hold things during the procedure. The good news is everything will fit and work as stock. The bad news is the cost - one shop quoted me $100 to repair such damage. On top of the carb-rebuild cost itself. Final choice is to find a donor carb and replace the broken piece(s).
Over the years, we have bought the remains of several shops that used the self-tapping fitting or worse; the fitting with the O-rings. We have contributed several hundred of both kinds (all new old stock) to the dumpster!!! Any carb coming into our shop with either type is automatically pitched! Unless this is a really rare high performance model, would suggest looking for a donor carb (as suggested by Kirk) and replacing the center section. The helicoil is a permanent fix, and actually better than the original because of the steel threads, but is costly. If this is a really rare high performance model, have the heli-coil professionally installed. The heli-coil kits are VERY expensive, and one still has to fabricate the holding fixture. Jon.
Jon, have you ever seen long-term problems with galvanic corrosion after installing heli-coil? Usually steel & aluminum don't get along well over time. I wouldn't be too concerned about the coil-to-carb body, moreso the fuel fitting to the coil for servicability. Devon
Devon - no, have not seen any problems of this type. Remember the Q-Jet body is zinc, not aluminum. Most (granted, not all) of the fuel fittings are zinc electroplated steel. So you have a steel fitting and steel threads. I suppose a drop of anti-seize could be used on the fitting threads; but we have not seen nor heard of any issues with this. Jon.
Thanks, you're right...the zinc would end up being sacrificial over the entire carb so I doubt there's ever be much of a problem. Forgot about the composition here! Devon
The Carb Number Is 70 8240emd What Year And Size Is This Thanks WHAT about brazing using brass would that hold
The missing number is probably a "2" making the carburetor number 7028240 which is a 1968 unit. The thread in this unit is 7/8 x 20. Jon.
