Quadrajet Fuel Filter Housing Torque

[Greg L.]

I was wondering if anyone had a torque spec for the fuel filter housing on a quadrajet? The service manual basically says "tight" which can mean so many things. The threads in my spare 69 carb look pretty bad but I found a filter housing that has several more threads on it that I would like to try and use if it holds torque and I don't want to over torque it in the process of trying it.
Thanks.

[David M.]

Re: Quadrajet Fuel Filter Housing Torque

No torque spec to my knowledge. So not much. Just snug enough so a new gasket seals against the air horn without leaking. 5/10lb/ft at most.
Always use the new gasket. Early QJ use the black steel coated gasket. Later style use the white nylon.

Always tighten the filter housing first. Then hold that housing and snug up the fuel line. Make sure the housing doesn't move.
Same drill for the fuel line just tight enough so it doesn't leak maybe a few degrees tighter. You need to feel the compression fitting alignment for proper "seating" as you tighten. Its a feel not a spec. Wiggle it to find center while tighten with a (line) wrench.
Its easy to cock the line which then screws up the seat on the softer metal line. So inspect that and replace as needed.

Frankly if my threads were messed up on an original carb I would send it out for the heli-coil repair. Its preformed with the carb chucked into a fixture which allows for parallel machining. You only get one chance at the repair. Its not worth a leak/fire.
The "rethread" style fittings do not work well. Again a fire risk

Call on of these two vendors and see who has the longest waiting list:

https://quadrajetparts.com/service-fuel-inlet-thread-repair-heli-coil-installation-p-355.html

Cliff is The QJ Expert....

https://cliffshighperformance.com/

[Mark E.]

Re: Quadrajet Fuel Filter Housing Torque

I second David's advice. Also, do not use any type of thread sealer or tape and make sure the threads are CLEAN.

Cliff Ruggles at clifshighperformance.com is one of the best, if not the best, Q-Jet guys in the country.

[Greg L.]

Re: Quadrajet Fuel Filter Housing Torque

I had thought about sending the body out for the heli-coil but have been reluctant because I've heard the process isn't always successful and getting lost in shipping probably even riskier. This is why I was wondering if there was a torque spec of some sort so if I could achieve that torque I would consider the remaining threads that it has to be serviceable rather than risk loosing the body either to an off repair or shipping.

Thanks for those two sources, I'll consider them but first I wonder if anyone here in Canada still does the heli-coil repair?

[Mark E.]

Re: Quadrajet Fuel Filter Housing Torque

You might first install what you have using the advice above and see if there's a problem.

I've shipped three Q-Jets to have their fuel inlet threads repaired, all successfully. Three isn't a large sample size but you might call the resource of your choice and ask about the risk. I suspect it's close to zero with a qualified shop. Inlet threads are an Achilles heel of Q-Jets so it's a common repair.

IMO, the biggest risk with shipping is damage, not loss. Many folks under pack. Double box using lots of packaging material and you'll be ok. And be sure to remove the air cleaner stud. Insurance is a good idea too.