[SCOTTB421]

I have two Q-jet carb questions. The car is a ’67 GTO that I have had for a couple weeks. I cleaned off the carb and it is stamped ‘manufactured by Carter for GMC’ but it has a correct Rochester part number of 7027263 instead of a Carter number. That seemed a little weird to me. The service manual does not say anything about a Carter Q-jet that I could see. Is this typical?

The second question is more important. The threads in the carb for the fuel line connection are all screwed up. When I put a wrench on the connection it actually moved back and forth at the carb. The previous owner installed a thin metal ‘shim’ to try to get the threads to bite. The threads are so gone the nipple will just spin. Is there a repair for these threads or am I looking for a new carb?

[SCOTTB421]

I have two Q-jet carb questions. The car is a ’67 GTO that I have had for a couple weeks. I cleaned off the carb and it is stamped ‘manufactured by Carter for GMC’ but it has a correct Rochester part number of 7027263 instead of a Carter number. That seemed a little weird to me. The service manual does not say anything about a Carter Q-jet that I could see. Is this typical?

The second question is more important. The threads in the carb for the fuel line connection are all screwed up. When I put a wrench on the connection it actually moved back and forth at the carb. The previous owner installed a thin metal ‘shim’ to try to get the threads to bite. The threads are so gone the nipple will just spin. Is there a repair for these threads or am I looking for a new carb?

[Cliff R]

Stripped threads are common to the early carbs. We install heli-coils here and consider this the best repair in lieu of using larger self tapping fittings, epoxy, etc....Cliff

[carbking]

Carter made millions of carburetors (Q-Jets) for GM under license. These carburetors carry the same part number as the Rochester, and are legitimate "original" carburetors, if the plant code and date code are correct for the application. However, the 1967 "original" would have a round tag. The "stamped" 1967 carbs (other than a few very late production California only - 703xxxx) are "service replacement" not original.

Concur with Cliff on the helicoil as being the best repair (better than original), although tapping with an oversize tap and inserting an oversize fitting is less expensive than the heli-coil and as good as original.

The self-tapping fittings and epoxy are both better left to the "fly-by-night" used car lots.

Jon.

[Half-Inch Stud]

MY MOST PREFERRED repair is to epoxy the inlet using JB-Weld weted to a typical 3/8 flare seat in fine condition.

Never had such a repair unseat or leak. HIS

[SCOTTB421]

I am very new to this so any help is useful. I have never installed a heli-coil. Is it difficult or require special tools? I am a general contractor so the majority of my tools are geared for that. I have been buying what I need as I go. If I epoxy the fitting in for now can a heli-coil be installed later. I am planning on having the carb re-built this winter, but want to drive the car for now.
Thanks for the help.

[Greg Reid]

Whatever you do, avoid driving it until you get it fixed. That leaky fitting is how I lost my first GTO back in 1984. Engine compartment fire.
I haven't done that particular repair but I'll be the heli-coil repair is no more time consuming than the JB Weld repair. Most Heli-Coils can be bought in a kit with the tap included.
It's basically a device that simply requires the original damaged threads to be drilled out and tapped to a larger size.
The Heli-Coil is a coil made of steel. The outer wall of this coil fits the new, enlarged thread that you just tapped and the inner wall is cut in the original thread so you're right back to original equipment.

[carbking]

This is one instance where the heli-coil is best left to the professional. If the heli-coil is not installed perfectly, the fitting WILL leak. Also, while most heli-coil kits are readily available at your local autoparts store, this one is special, special order, and most autoparts store personnel will laugh at you. It is also quite expensive (about 10 times the normal heli-coil kit). Cost is ridiculous if you only use it once.

I believe Cliff offers this service ala carte. We offer it only in our own restorations. Maybe Cliff will chime in here.

And H.I.S., while I have the utmost respect for you, I must suggest here that you have been fortunate with this issue. J.B. Weld will get soft in the presence of gasoline, and eventually fail. As we stand behind what we sell, we always test materials before we use them. We tested J.B. Weld by mixing it as prescribed, epoxying two small items together, and throwing this into a babyfood jar with gasoline. It took about 3 months for the J.B. Weld to soften to where you could cut it with your fingernail. Needless to say, we do not use this product around gasoline. I would highly suggest that you take a second look. Better to be safe than sorry.

Jon.

[BVR421]

ScottB, could you take another stab at describing what you have found to be a problem?
guys take another look at his inital post. The description of the "screwed up" inlet sounds exactly like a stock original setup. It is not clear where the problem is or if there is a problem. The thin metal shim between the filter housing and the body is stock, the fact that the housing wants to rotate when the fuel line is disconnected is known by all who have ever disconnected a fuel line from a qjet.
There may indeed be serious issues with the fuel line or inlet but from the description its hard to tell. How many times have you heard the expression "screwed up" used when someone is unfamiliar with a particular component?

[SCOTTB421]

The threads in the carb are flattened out. The fitting pulled straignt out of the carb with out un-threading. I'll look at it when I get home and try to take some pictures that I will post tomorrow.

[SCOTTB421]

Attached is a picture of the metal shim I was trying to explain. When I use it with the fitting it will only snug tight then the threads slip. I assumed that the shim was added by a shade tree mechanic or something.

[Holeshot71]

Check this out...


http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW

[Cliff R]

We offer heli-coil installation as a separate service. Give us a call for specifics, 740-397-2921. We also install bronze bushings for the throttle shaft, most well used carbs also need this repair....Cliff

[Half-Inch Stud]

DO NOT use that sleeve repair. Oh the corrosion explosion that follows.
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Carbking,

my JB Weld "Repair" is actually my "do it on all my Q-Jets" standard repair method.

The JB-Weld gets plasticy on the constant gas contact but the thin barrier film along the length provides an integrated creap path that "takes forever" for the gas to migrate.

With this in mind, such fuel inlet fittings have been JB-Welded with far more than 10years duty on them. Hot engines cold winter& winter fuels, hot summer & summer fuels.

Worst-case would be a seep, yet no seeping or wetness has been noticed.
-----------------------------------------------
Overall, I trust there is a better epoxy than the JB-Weld. So, I suggest the Repair Method is fine for the hobbiest and professional.

Paul Spotts looked and cautioned me too, saying that I ought to "buy this white epoxy" from some NJ company that is specifically designed for constant gasoline contact. I agreed with that.

To support your & Pauls' notion: I have noticed that Antifreeze attacks other epoxys to the tune of turning it to gum. JB-Weld repair of 2 different radiator gashes have held on daily drivers...so that shade-tree qualification testing keeps me content with the antifreeze immersion, FWIW.

Could you recommend a better epoxy?

Thanks for your respects.
Respectfully,
HIS

[carbking]

H.I.S. - my comments were not meant as an attack on J.B.Weld per se; rather the use of ANY expoxy around the fuel inlet fitting. I use J.B. Weld in areas which have no gasoline.

For the fuel inlet, several good repairs exist. They are, (in order of ease, and least expensive first):

(A) tap the body deeper (more threads) and install a nut with longer threads.
(B) tap the body with a slightly oversize tap with the same thread (these exist commercially - fabrication of a special tap not required); and use an oversize nut (also available).
(C) insert a heli-coil (if you do not wish to do this yourself, Cliff Ruggles offers this service a la carte).

If you are using a not-standard fuel line:

(A) install the heli-coil (see "C" above)
(B) acquire a die with the thread of the original nut (most, BUT NOT ALL PONTIACS will be 7/8 x 20). Depending on your needs, this may have to be fabricated. If so, I can order ANY die for you.
(C) make a "blank" nut
(D) acquire a tap with the thread of your non-standard fuel line
(E) thread the "blank" to accept your fuel line.

More expensive than J.B. Weld - certainly!; BUT MUCH SAFER!

Jon.