I love my ThermoQuads, but one of them has a problem

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Bill Crowell

Bill Crowell

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One of my TQs keeps leaking and dumping fuel into the engine. I'm not a real TQ repair hotshot myself, so I had a known good carb mechanic glue it back together, and it was running pretty well, but apparently it has failed again so maybe he missed something? (FWIW he's got the TQ's on my other LA and my RB engines running perfectly.) Any tips on what to look for when we take it apart this time, or about how to permanently repair it? Thanks a lot, guys.
 
Typically you epoxy the "wells" on the bottom of the bowl. Where they were glued originally.
 
That's what the mechanic did the last time. I need to disassemble it and see where it has failed. I'll try to post a picture of it when I do.

Any particular kind of epoxy, or just the generic kind?
 
What model number?

I have bowls but they vary year to year. So I just can’t send one to you. A picture looking down into the bowl would help as well if there is a vent in the primaries or not.
 
I use JB Weld. You also have to use it on Quadra-Jets in the same place and for the same reason. Also make sure you are using brass floats. My TQ's are still good to go after almost 50 years. The best carb ever made for the street. You have to do quite a bit more to get a Quadra-Jet to get to the same place.
 
check the primary well seals . if they crack or get hard gas will drip into the intake .
 
Good tips and advice from everyone that knows TQs.
I love them too; great street carbs, if a lil time-consuming to ballpark the MJs. Super-nice carb if you have the tuning kit for it.
 
Here's where I'm at on my TQ. It's a 6461S (has the large 1-3/8" primary bores) that I'm using on a fairly hot 360. The primary well extensions had fallen off again. They were glued on with JB Weld plastic epoxy last August, and I think they began to fail pretty soon afterward. JB weld just doesn't work (I think the ethanol must attack it?), so don't waste your time!

Thanks, Rusty, for recommending Seal All. I'll try to find some (unfortunately I don't think Home Despot sells it, though). Some other TQ hotshots are recommending Miller Stephenson's MS 907 epoxy, saying it is really the bee's knees and the "only" thing to use (can provide links if anybody wants them). I sent Miller Stephenson an inquiry begging them to sell me some because I couldn't find a distributor, but they have yet to respond. I think maybe they don't sell to individuals and/or have a large minimum order, but I'm not sure.

Would anybody know of any plastic epoxy that will stand up to ethanol, and that you can either buy at, or order through, Home Despot?

So I had better learn to work on TQs! (I've already learned that when your idle goes to hell, you start smelling gas and the idle adjustment screws don't do anything, it is probably because the TQ is dumping way too much fuel into the engine, and maybe you'd better check into it!)

I ordered a pair of brass floats and "O" rings from Walker Products. I'm pretty sure that Walker is shipping the latest, up-to-date version of the "O" rings. I have the carb disassembled and my big-assed old van is sitting in my shop, taking up room, while I wait for parts. Walker still sells all the TQ parts (they're out of stock on the fuel well extensions, though), but they've stopped selling complete kits themselves and have RustyRatRod's employer sell them instead. That's convenient for me because I always go to O'Reilly's anyway. (Did I mention that I play the O'Reilly's theme song over and over because then I can't hear those irritating voices?)

It sure would be nice if I could learn to assemble a good TQ! Having a mechanic do it is getting to be ridiculous ($). It doesn't really look that complicated (famous last words); I am watching all the rockysroadshow rebuild videos on youtube; and I'll be happy if the damned thing just works decently and doesn't leak.
 
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Ether version of this book has everything you wanted to know and maybe something you didn’t wanna know about the Carter line of 4bbl. carbs including a step by step rebuild of each of the four 4bbl. carbs Carter made. Take your time and realize that the carb may very well have to be tweaked on the engine.

Same author for both books. The one on the left is the updated version.

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