7026240

[drhach]

Hi everyone, new guy here. I just purchased what is numbered as a 1966 QJ for a Buick. However, I'm confused. It doesn't have the disk. There's no provision for it and the carb number is stamped in to a pad like it would be on the later carbs. It doesn't look like a re-stamp. I would have thought that if it were a later carb, it would be a service replacement (7041304). But that isn't how it's stamped. Could it be that this was produced after 1968 and factory stamped with this earlier number?

I guess my first concern is ordering replacement parts. Also, what should I look for to indicate vintage (if it matters)?

Dan

[Kenth]

A service replacement should have 7026240 stamped were the later units are stamped.
Also the date should be stamped at the same pad, four digits, last one the year it was made and the first three is the day that year.
Also, no plant code (two letters) on the service unit.

[drhach]

So, a service replacement would have the same number as the original? I thought service replacements got '7041304' stamped on them. Also, the only other stamping I can find is BMA some distance after the 7026240. It is pretty filthy though. Maybe there's something that I missed. I'll clean the pad a little better and see if I can find anything else.

[Kenth]

Here is a picture of an original 7026240. On the tag is stamped 7026240 B D6 (Date) and MA.

[drhach]

Here's mine. The only other thing is below where the disk would have been are a couple of stamped dots. But there is nothing indicating date. Like I said, I thought that if this was a service replacement, it would have the service replacement carb number. I guess it doesn't matter. I'll try to measure the float fulcrum when I open it. That may give me a better sense of what I'm dealing with.

[Kenth]

Looks like someone made a "frankencarb"?
Those stamping does not belong on a 1966 7026240 Buick Quadrajet, should have a disc like in my pic.
Need to see all parts of carb and measure the calibration to know for sure.

[drhach]

So someone had a blank casting and stamped their own number? I don't see any evidence of overs tamping or grinding.

[Kenth]

Area were the ring holding the tag sat looks tampered with, so i guess yes, they stamped their own number on a virgin surface.

[drhach]

Well, my hope is that it actually is a later casting that will have the better float fulcrum and not have the weighted secondaries. I was more interested in the manifold than the carb. I considered it a happy accident that I got a carb and manifold for the price of the manifold. The commentary that I've read from Cliff is that the 66 carb isn't preferred. The manifold is a 1966 only option for Buicks. If I actually have a later carb, I'll consider that a bonus.

[Cliff Ruggles]

I try to avoid the 1965-66 units and for good reason.  They have many defects and the factory knew it.  Right to start with the fuel inlet plunger valve and bypass system is a hopeless MESS.  Even with the upgraded parts they still leak easily at the bypass if you push in the plug with the "O" ring on them. 

The weighted secondary deal is HOPELESS!

I still restore a few here and there, but end up rejecting quite a few of those early units for casting problems and even if they are in decent shape they will ALWAYS leak at the bottom plugs and often at other plugs driven into them so seal off drilled passages, etc.......Cliff

[drhach]

Thanks Cliff. I've decided to cut bait on this unit. It never was meant to be a "purist" application. My 62 never came with a QJ.

I found a guy near me with a unit from 1978. I get the better damping, better float, APT, etc.

Regards,
Dan

[Cliff Ruggles]

Good move all the way around IMHO.

I like and use the later carbs if/when being a purist isn't part of the equation. They are just better carbs all the way around right down to converting them to E-choke so they will work on any intake/application.......Cliff