QJET Rebuild part #1 [Archive] - Chevelle Tech

: QJET Rebuild part #1


Gene Chas
Jun 20th, 99, 11:29 AM
Just put the top back on my junkyard Q, and I thought I'd share a few tips. There are folks out there more experiecned with the Q than I, but I rebuilt a bunch of these when I was a kid and had good luck.

Don't forget the two screws in the primary airhorn. Start with these when you retorque.

The choke rod is a PITA and I find it easier to disconnect it where it links to the choke lever in the main body. Upon reassembly, I'll fish the choke rod back onto the choke lever from through the top and then reconnect to the air horn.

I always polished the piston rod with fine emery cloth just to make it work more smoothly in the bore. Rinse with real hot water and blow dry with a air can. Also, you can put the emery cloith around a pencil and clean up the piston bore too. Dont start sanding away at this thing. You remove too much metal and the sucker may not seal.

Found the best way to rehang your primary metering rods is to get the loop of the retaining spring near the hole in the hanger and then loop the top of the metering rod into the hanger and the spring.

Always check the ends of your metering rods for deformities. The qjet I just finished was reman by Holley ( odd? ), but one of the secondary metering rods was bent. I could've done that when I disassembled but I don't think so.

Although my instructions said not to, I always disconnect the secondary metering rods from the carb. Trying to line up the four rods, plus the two metering rods upon reassembly is too hard. They're pretty easy to "feeL' back into their ports.

Even if you don't remove the carb base, check all the bolts for tightness. You'd be surprised how many loose bolts you'll run into.

I can't tell you how many times I reassembled the power piston only to remember that the float/needle assembly goes on first. Put the float in first and set it, then reinstall the power piston.

With those plastic rings that hold the power piston in, if I know I'll never open up that carb again ( for tuning or whatever )I'll put a dimple into the metal just surrounding the ring to hold it in. ( Be gentle )

Well I haven't done this in twenty years, but it felt like yesterday so I thought I'd share a few pointers.

Oh, some new tech for you guys that don't have air:, those air cans you get at the computer stores. Mint for blowing out holes and such.

Good luck with your Qjet. I'm might just rebuild another one with the "monster" primary bores ( 800 cfm) for my bigger big block.

Gene Chas
Gold #62


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[This message has been edited by Gene Chas (edited 06-20-99).]

[This message has been edited by Gene Chas (edited 09-15-2000).]

Wally
Jun 20th, 99, 12:00 PM
Tri-Man

Your shifter is going out UPS Monday, happy mixing. I took the handle off so it would fit in a smaller box

Wally
Gold #67

Quadzilla
Jun 20th, 99, 6:59 PM
The Quadra-Jet can make anything hum... I threw one on my 307 straight from the junk yard... started right up, took her out into the street and burned up the tire for about 20 feet... all this with a 307/GP and 2.56 peg leg.. had it rebuilt and it runs like a dream!

Can't wait to get it on the 350 that was susposed to go in in December then May and now July http://www.chevelles.com/forum/frown.gif

------------------
Francis Taracido
Sniper0666@aol.com
Proud Patron of Quadzilla

Gene Chas
Jun 20th, 99, 8:02 PM
Wally, the old shifter has "locked up" my Muncie again. I don't know a thing about these, I've always been an automatic guy. I "unlocked it last time, this time the tranny seems pretty locked. I tore the old unit off the minute I saw how bad it was. It is junk. I would have never run such junk.And now I have a Muncie problem. Will I ever get the tripower on? Will the '67 ever get on the road after a 20 year hiatus? Stay tuned.

tom3
Jun 20th, 99, 8:21 PM
Gene; Chances are good that the shifter lock up might be a problem in the side plate. Might check for a firm "detent" when you shift the levers back and forth. tom

[This message has been edited by tom3 (edited 06-20-99).]

nightowl
Jun 21st, 99, 3:30 PM
Gene, I've got a 69SS396 325hp with i believe to have a rochester quadra-jet.
well it says q-jet on it, but made by carter, so i'm puzzled. it sets on a q-jet intake manifold don't know if its cast iron or aluminum. heres my? i need to get it rebuilt and come to find out the only shop listed in our ph book say because of a law suit that you can't replace the bushings in the throttle linkage, so there for the carbs not able to be rebuilt, true or not? now I've been told that i can put a 750 holly on it with a adapter and be good to go, with a little more hp to boot. do you know what it should cost for a new quadrajet, and what size is a quad 600, 650, 750 ???

Gene Chas
Jun 22nd, 99, 7:02 AM
Nightowl, are you sure you need to replace the bushings? BTW, they're not replaceable on a Q, so I don't know what your rebuild shop is saying, maybe that they don't want to hassle with it... I have a Holley 750 with loose bushings, I know because gas was leaking out one of them, ( motor wasn't running ). Unless you have big slop like an old whore, I wouldn't worry about it. Sure the 750 Holley will work with an adapter.

According to Wally, the Q flows about 750, although there are bigger ones out there. I saw a few at the junkyard where I bought mine. I think I might just buy one ( $50 ) and run it to see. I think I might be able to squeeze 800-825cfm out of one, which would be primo for my 427.

A new Q? I donno but figure any new carb is $300+. If you have a functional 750 Holley why not take the risk of rebuilding your own Q. My rebuild kit cost $11.50 minus the 2.50 Forest City frequent buyer card is 9 bucks. What's the risk? If you really want to do it right buy the book ( Doug Roe I think ) on Q's , then you'll have 30 bucks invested in it.

Len
Jun 25th, 99, 4:50 AM
Holly offers a rebuild service & they rebuild just about anything!

http://www.holley.com/HiOctn/Sales/CustShop/CustShop.html

Also, most of the shops that offer custom rebuild services for Q-jets, can bore out the trottle plate install and ream bushings to size.

I've also seem these bushing kits which include the correct size reamer for sale as well. I believe they advise using a drill press (prefered) for any drilling.

Gene Chas
Jun 28th, 99, 1:35 PM
Sure Len, you have to keep those bores as square as possible. Wouldn't consider it with a hand held.