The main fuel connection to my carb will start leaking at random times. I don't want to torque down on it too much but when it leaks I give it another 1/8 turn. I don't think it will go anymore now. Twice I have had it start leaking, once pretty bad after I left a show. I could smell gas when at a stop light. Today it started leaking after a 15 minute drive, had not leaked for over year before that. Is there a better gasket to use where the fitting meets the carb?
Greg Gessler has several different gaskets. The 72 and up carburetors use the internal seal which is much better. I'm assuming you have a 68 Q-jet. https://quadrajetparts.com/quadrajet-misc-gaskets-seals-c-128_25_40.html
The correct repair is to have a heli-coil installed. Thick gaskets are a temporary fix for a permanent problem. Keep in mind that you are messing around on the PRESSURE side of the system. I cringe when folks cut the solid metal line and install an external filter, rubber hose and clamps, best way I know to burn your pride and joy right to the ground. So keep your insurance paid up, especially the life insurance so your wife's new boyfriend will have more money to buy premium steaks to cook on your old barbeque grill! It's pretty common to see issues with the pre-1972 units and NEVER use any of the aftermarket over size/self tapping fittings, or any expanding type fitting as they will ruin your carburetor often making a heli-coil repair impossible......FWIW.....
Thanks Cliff, I don't think the threads are stripped but I will look closely at them when I remove it. I don't have an external filter so no barbecue for my wifes pool boy... I assume Teflon pipe tape on the threads is also a no-no?
NEVER use Teflon tape anyplace in a fuel system, unless you want to find yourself sitting on the side of the road waiting for a roll-back!.....LOL To test the inlet thread screw the filter housing all the way in, back about 1/4 to 1/2 a turn and see if it wobbles. Or you can just put a 1" wrench on it and torque to it down pretty hard. If the threads are on their way out you'll find out pretty fast.......
Cool story about Teflon tape. About 15 years ago I did a carb for a long retired Pontiac Super Stock racer for an older race car he was bringing back to life. Pretty fast car, nostalgic SS if memory serves me correctly. So we're at the Pontiac Tri-Power Nat's for the cars big debut and it leaves really hard then noses over and stalls out. They mess with the car most of the day trying to salvage a decent run out of it with zero success. Then as expected a couple of guys from his pit crew wonder over to my site with the carb I did for him. I hear some mumbling under their breath about Quadra-junk and they should have used a Holley in the first place, blah, blah, blah, but am used to that deal and pay it no mind. So I get to "gut" the carb at the track and it's FULL of tiny strings of Teflon tape. I clean it all out, they make like 1 or 2 good passes then I get it back again, same thing, FULL of tape. So I wonder over to look at the car and someone on every single fitting in the fuel system used a roll of Teflon tape on the NPT threaded fittings....wonderful! At some point they even tried a big custom built Holley and it suffered the same fate and actually ran slower than the Q-jet on it's best pass when it did work correctly. So moral of the story is to let the NPT fittings do what they do best, seal on the tapered threads and at most use a tiny dab of pipe thread sealant on them, but never any tape........FWIW.......
Ive used a crushable copper washer on those before. I also measured and found that you can put an aluminum or copper washer at the end of the threads since it dosent bottom out. That worked too. After that I realised the 68 carb was ment for a 430 and was the smaller casting. So get a 75 or newer carb and get the benifit of more cfm and newer design longer filter better sealing deal with adjustable apt. Ive seen the ole teffelon tape job on plenty of transmission cooler fittings. On the case the flared ones. Thats always funny.
I spent years looking for a correct date coded 68 400 carb to replace the 43o carb that was on it, I have the receipt from the original owner turning the original carb in as a core back in 1979. I think the larger gaskets I ordered should solve my problem since the threads do not appear to be stripped.
