Q-jet, Stripped threads
Thread Starter
Melting Slicks
Joined: Jul 2000
Posts: 2,107
Likes: 14
From: Lancaster PA
Q-jet, Stripped threads
Last week I was returning home in the 68 when the Q-jet flooded badly and I had to get a ride on the rollback. I assumed it was needle and seat problem, which it turned out to be a small piece of dirt stuck in there. While trying to change the filter, the threads stripped on the big nut that holds the filter in. I got a repair fitting from Dorman but it is the same size as the original. I need a slightly oversized fitting that will self tap into the carb body. Does anyone know where to get this fitting? Thanks, Craig :chevy
Melting Slicks
Joined: Oct 2000
Posts: 2,142
Likes: 195
From: Englewood FL
Re: Q-jet, Stripped threads (CF6873)
Have read previous posts from Lars and others to not use an oversize
fitting. You should remove the carb. and send it to a shop that has
the proper tools to install a heli-coil. Then use the original size
fitting. It the threads on your fuel filter nut are worn, new fittings
are still available from GM.
fitting. You should remove the carb. and send it to a shop that has
the proper tools to install a heli-coil. Then use the original size
fitting. It the threads on your fuel filter nut are worn, new fittings
are still available from GM.
Drifting
Joined: Mar 2001
Posts: 1,514
Likes: 1
Re: Q-jet, Stripped threads (mark79,80)
Have read previous posts from Lars and others to not use an oversize
fitting. You should remove the carb. and send it to a shop that has
the proper tools to install a heli-coil. Then use the original size
fitting. It the threads on your fuel filter nut are worn, new fittings
are still available from GM.
fitting. You should remove the carb. and send it to a shop that has
the proper tools to install a heli-coil. Then use the original size
fitting. It the threads on your fuel filter nut are worn, new fittings
are still available from GM.
Scott
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Re: Q-jet, Stripped threads (Scott78)
I agree with the above advice.... but if you're bent on using the over-sized fitting, it is available at NAPA and other stores in the "HELP" line.
Be aware that it comes in different thread sizes, both where it screws into the carb, and, where the fuel line screws into it. You have to know what size(s) your own fitting is before you go shopping.
Be aware that it comes in different thread sizes, both where it screws into the carb, and, where the fuel line screws into it. You have to know what size(s) your own fitting is before you go shopping.
Pro
Joined: Aug 2000
Posts: 530
Likes: 11
From: Lewes, Delaware
Re: Q-jet, Stripped threads (CF6873)
A place in Bristol,Pa. called Bowen Automotive,(215-943-6639) quoted me to rebuild my Q-jet, Tap and put a helicoil in it was 165.00 done. Heard he does good work but never used him.... :cheers:
Team Owner
Joined: Aug 2000
Posts: 21,453
Likes: 461
From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
Cruise-In VI Veteran
St. Jude Donor '08-'09-'10-'11-'12
Re: Q-jet, Stripped threads (Rich80)
I have used that "NAPA" oversize self tapping fitting with success, but I did'nt use it as a permanent fix. Also, you have to use an external filter when using this "self-tapping" fitting, as the instructions tell you it was not made to be taken in and out. Once you install it WITH NO LEAKS do not remove it. Should have the carb repaired properly and as always, carry a fire extinguisher.
Safety Car
Joined: May 2001
Posts: 3,758
Likes: 3
From: Surrey
Re: Q-jet, Stripped threads (CF6873)
I've got exactly the same problem in that a previous mechanic has damaged the thread & put it all back together with PTFE tape in there. This clogged the filter. I've removed the filter & fitted an external one. After many leaks I've now got it fuel tight, but don't expect it to last (now carrying a fire extinguisher!). As the thread is a large fine one (anybody know the size & tpi - I should have measured it when it was all apart but don't want to take it apart again) nobody I know has helicoils that size. It would have to be a special order so would cost lots of $$.
My plan was to stick with an external filter, cut a thread in the reduced diameter part of the filter housing & make up a large slug/plug to screw into the new thread with a sealing compound on the thread. Obviously the plug would have a hole through it & a thread for fitting the fuel line on. Is there any reason why I shouldn't do this (apart from being called Bubba!)?
:cheers:
My plan was to stick with an external filter, cut a thread in the reduced diameter part of the filter housing & make up a large slug/plug to screw into the new thread with a sealing compound on the thread. Obviously the plug would have a hole through it & a thread for fitting the fuel line on. Is there any reason why I shouldn't do this (apart from being called Bubba!)?
:cheers:
Tech Contributor
Joined: Aug 1999
Posts: 14,376
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
Re: Q-jet, Stripped threads (CF6873)
Guys -
I have bought all the tools and parts needed to do the inlet thread repair the right way. I can machine out the inlet, re-tap it in a fixture I built, and install new, stock-sized stainless steel threads into the carb. The repair comes out better than stock, and it allows you to use a stock inlet fitting with a stock filter. Due to the cost of the tooling, I have to charge $50 for the repair if you send me just the float bowl and you do the rest of the carb rebuild yourself. If you send me the entire carb, I have to do a rebuild on it after the machining to assure removal of all the metal, so I have to charge a nominal fee for the complete setup. Contact me if you need more info.
V8FastCars@msn.com
I have bought all the tools and parts needed to do the inlet thread repair the right way. I can machine out the inlet, re-tap it in a fixture I built, and install new, stock-sized stainless steel threads into the carb. The repair comes out better than stock, and it allows you to use a stock inlet fitting with a stock filter. Due to the cost of the tooling, I have to charge $50 for the repair if you send me just the float bowl and you do the rest of the carb rebuild yourself. If you send me the entire carb, I have to do a rebuild on it after the machining to assure removal of all the metal, so I have to charge a nominal fee for the complete setup. Contact me if you need more info.
V8FastCars@msn.com
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Racer
Joined: Apr 1999
Posts: 299
Likes: 0
From: manalapan, nj
Re: Q-jet, Stripped threads (lars)
Lars just did this repair for me and a carb rebuild. Quick turnaround time, I had mine back in 1 week fromm date I shipped. I would highly recommend him to all. Any questions you can email me.
