Carb Leak at Fuel Filter

[tanman]

This is my plea for help before I just buy a new carburetor...

I've tried the following
- replaced the fuel filter
- white teflon tape
- yellow pipe tape
- red loctite
- silicone gasket sealer


Any ideas on another magic goo or a resource for purchasing a replacement would be helpful.

[85lebaront2]

When I was redoing some transmission cooler lines on a friends G30 van, I bought a bottle of Permatex hydraulic sealer. It starts as a white goo about the consistency of toothpaste and hardens fairly well. Before you go to that, check that the top of the carburetor doesn't have a hairline crack at the bottom of the threaded hole.

[Gary Lewis]

Yes, it isn't uncommon for the casting to crack if someone has really cranked on the fitting.  I think those are tapered pipe threads, and you can really generate a lot of force by overtightening.

[ArdWrknTrk]

They're straight threads if it is a filter housing, and not just the filter threading in.
4180's were notorious for that and an oversized, self tapping housing was available (from Dorman, I think)

If it's just a YF, 2100,-50, whatever... Where the filter itself screws in, then IDK.

[Gary Lewis]

Looks like a YF, but I don't know what the threads are where that filter screws in.  Still, I'm guessing NPT.

[ArdWrknTrk]

Yes, it's the filter itself, not a housing.

I think the 4V's were 7/8-24 or something equally odd.
It's been a few years...

[HBF84]

I tried this on my filler hose when I was making a patch a few weeks ago and so far so good.  It has an impressive gooey consistency that should work if the carburetor housing isn't cracked.

[myrl883]

It's been touched on, but you'll probably find that the carburetor is cracked from a past mechanic overtightening a fuel filter. It was really common on those carbs. I've never been a fan of tapered pipe threads in aluminum.

[Gary Lewis]

I've seen aluminum intake manifolds cracked because of someone overtightening tapered threads in the temp sender opening.  If you can crack an intake manifold, cracking a carb should be easy.  

[85lebaront2]

If it's like most of those gold colored carburetors it's not even aluminum, it is a zinc alloy called "pot metal" and it will crack, heat creep and strip if you look at the threads hard. The Rochester Quadrajets were famous for stripped inlets.

[ArdWrknTrk]

I've never been a fan of Zamak (zinc, aluminum, magnesium) pot metal for anything.
Holley has finally been producing their carbs in straight aluminum alloy.
Whick has a little more forgiveness...

If the boss is just stripped, and not cracked, you can probably install a thread insert.