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Old 09-17-2012, 08:58 PM
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Originally Posted by fasteddy_1947 View Post
Got nifty cheapo Q-jet from seller on e-bay. Was happy as that pig in slop when it came. like everything else I ever got, first thing had to do was take it apart. Being older than dirt, my second thought was to find something out about this animal, before start messing with it. Am right at home and happy with Rochester 2 bbl and have been running one on my '51 coupe (327) for 20 years (time to do something else). So, everything I read says get the Cliff Ruggles book first. So I did. Wow, this thing aint nothin like I thought it going to be. Not even close to the 2 bbl. But got it, so gotta do something with it. Wasn't worried bout specific configuration, as it eventually (maybe) going on 350 in 39 coupe. So on initial and subsequent inspections here's what apparent problems with this are. 1) It has been backfiring through the primaries. Heavy soot/carbon build-up in air passages (primary side). 2) Missing stuff: choke pull-off, choke to secondary lockout linkage (and I don't know what other linkages). 3) The throttle valve shaft was turned 180 deg w/linkage to secondary throttles turned 180 the other way. Primary throttles wouldn't close, but didn't figure out why until got it down and saw that if take linkage/levers off and turn throttle shaft 180 deg. the throttles work as they should. Once got it down and started cleaning, found that accelerator pump check valve well in fuel bowl was leaded over (?). Under the lead is the ball. the cap screw is gone. Have basically identified the original application for the carb. and am pretty confident that will be able to get stuff for it, someplace. But don't know if it is going to be worth the effort. Am wondering if anyone has any good tips, or if I should just toss it or make ashtray or something out of it. Have second (junk/parts) Q-jet coming this week. Will go from there (maybe). Right off, am I missing something obvious, and what else do I need to be looking for on this?
I feel ya' on trying to buy a decent core of eBay. The thread "Worth buying a used carburetor and rebuilding or just buy new?" tells some of what I went through not too long ago trying to buy a decent core.

The only 2 bbl carb that resembles the Q-jet is the DualJet. It's basically the primary side of a Q-jet and was used in the late '70s and early '80s. You prolly have a Rochester 2G on the engine now; it bears no resemblance to the Q-jet.

You can still get quite a few different Q-jet carburetor linkages. There are other parts suppliers, too.

After you get the core that's coming, see what you need and go from there. If possible- and if needed- taking some clear photos will help see what's up.

It sounds like the throttle shaft(s) were removed. Often the throttle blade screws are broken off because the peened over ends weren't ground off first so hopefully yours aren't broken. The secondary throttle shaft can be a bear to reassemble, so unless there's a real need leave it as-is.

You'll want to check for excessive wear of the primary throttle shaft. If it's excessive they can be bushed but this is expensive. There are other trouble spots to watch out for as well.
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