I picked up a Rochester Quadrajet carb # 7028212 DH for a good price. I found out that it is for a powerglide car. Decoded, the "8" means 1968 and the "1" means Chevy. However, I see now it's for an automatic trans car. The numbers should have been 7028213 DY for my car which has a 4 spd manual trans.

What is the difference between the automatic Q-jet carb and a four speed Q-jet carb?

The Q-jets are great carburators and would love to rebuild it for a spare. Can I make it work? Can I change the throttle arm or is internal changes I have to make during the re-build?

RayG

Ray, For goodness sakes alive, don't ever put that carb on your 4 speed engine! Ship it out here and I will try to get some use out of it, it is a little too light for a boat anchor but it will make me a good paper weight. I will be pleased to pay for part of the shipping and handleing. By the way I have a shipping box for that carb. I had to buy one for my 1968 Impala 327 with A TH400 .

Just kidding! I do have a nice shipping container, since a couple of years ago I had to replace my original QJet, corrosion had eatten plumb thru the bottom fo the bowl and the threads of the needle seat were completely gone. I ordered one rebuilt by Holly for around $130. I would think that a good parts manual will have the correct numbers. The one that I have is a dud, it is on a CD and almost impossible to pull up the right page.

Shirly you jest Macky Wacky...Try and find a workable Q-jet manufactured in 68 with a Chevy digit in the number. I don't have a boat but it's 10 lbs. with all the gunk on it. (It could make a good anchor seeing that it's on the original manifold just to keep it out of sight of those garage junkies).

But I'm serious on rebuilding it as a spare. I talked to one of the throw back mechanics at work today and he says it was a great find for 40 skins. He also says the difference is in the throttle. Change the lever or rig it to work and I'd be home free. May be?

Not sure until I hear from a couple of the brainiacs here.

Anybody here want to keep this original Chevy 68 Q-jet from becoming Mack's anchor? Let me know about Q-jet #7028212DH vs 7028213DY.

Yeah, I think that the choke, the throttle pull of and throttle linkage is what is different, of course many more Impalas were sold with automatics Pb & PS than the 4 speed jobs. All the casting numbers matched on the replacement QJet that our local home grown parts house guru ordered for me as a rebuilt original carb from Holly. We also have a excellent Qjet mechanic here that was going to rebuild the original carb and do new welch plugs etc. but my core was junk, it had had a JB Weld rebuild sometime in the past. I kept it for parts because I was only going to get $20 core charge. I figured the internals and the choke oven were worth over $20
I bolted on the newly "Remanufactored Qjet", set the air and idle and it ran like new!, that is my test...does it run well?
I would not buy a used Qjet off a car, it may be junk.

Well Mack, your test of "does it run well" is going to wait until I rebuild it.

I cleaned it up a bit yesterday making sure I didn't let the gunk cleaner stand too long on any internal rubber or plastic parts. All the levers and linkages are free and only the rod between the manifold choke spring and carb is missing. I don't think this has ever been rebuilt. It was so caked with gunk that I believe this carb was looking for some attention for a very long time.

The trottle pull off even has good suction.

Can't call it quits just yet. Besides the swap meets will be starting soon. I may find what I need.

Good luck with your rebuild.

Ray,
Would you be using it on a small block or big block.It's a small block carb 327/250 type.At $40 that was a great deal.Definitely worth a quality rebuild kit along with a new float.
There were only two sizes in terms of cfm's of Q-Jets.There is a difference between auto and manual applications.Biggest is the primary metering rod circuit.That could easily be made to perform nicely on a man trans car with a simple rebuild/jet change.
I see the late 60's Q-Jet cores go for $80-$100 all the time.
There should be several good source books at your local Library on Q-Jets.
Or try a pro Q-Jet re-builder like Jim McGowen at the QuadShop Good luck,Jim

Sorry wrong addy on Jim McGowen.His email is quadshopjuno

Big thank's Jimpala70.

Actually I got the original manifold with it for a total of $70. It's for a 68 350. The Q-jet is a 4MV, and the manifold dates out to August 67.

I've been cleaning both the last few days and the carb is looking real nice, but at about half throttle it has just under a 1/16" play side to side in the primary thottle. Secondary has no play. All the setting screws turn easy and the springs are all strong.

I have re-build instructions books and manuals so with a good kit I'm thinking that I'd like to try the rebuild myself. From what I've read so far the side to side play in the primary causes leaking, and the fix is to ream the trottle shaft and install new bushings. I would need that type of kit. Thanks for the McGowen lead, I'll keep it in mind. What kit's would you recommend? I've seen Jet kits and Dr.Carburator sells one. Prices are in the $30 range, with extra $'s for the brass float. I'm sure there is more kits out there.

Thanks, RayG

Ray.....

Have you looked at these guys ?

http://www.daytonaparts.com/index.html

Having fun yet????

Hi Ken!

Yeah, I'm having fun now. I've started to spend some time in the garage since it warmed up a bit.

I picked up that carb and manifold as a spare/possible replacement for "you know what" that's sitting on top of my engine now. It was a good find and if I ever want to slow things down a little I may make the swap.

Thanks for the lead. Some great vintage stuff there for sure.

RayG

....hmmmmm Didn't realize that the 350 came out in 1968, was it on a Corvette?
I have been about ready to replace our original 327 in our 68 Impala Sport Sedan, that needs a overhaul (uses a Qt. of oil every 500 miles) with a 2 barrel carbed 350 or 305 crate engine with a manual fuel pump, for touring, but was afraid it would be a hot rod mod.

The first 350 was in a 1967 Camaro. In 1068 it was available in the Camaro, Chevy II, and wasn't available in the Corvette till 1969.

Thank you Gene for setting old Macky straight. I was going to try, but was at a loss for words.

So the 350 was not available in the full sized Chevrolet for 1968, is that correct? Or was it?

No- you had to wait until 1969