Anybody know the correct part number for a carb on 1972 442 W30 (F87X) with a automatic? I have multiple documents saying different numbers in books and on the web. I show 7042953 and 7042251. I'm leaning to 7042953.

Please reference your source for the number.

Thanks,
Mike

 

7042251 - W30 and 442 455 with automatic trans
7042953 - W30 455 with Standard trans

 

7042953 is the W30 carb for 72, auto or stick!

Cheers,

Sam

 

Supercarsunlimited publication "by the numbers" shows 442 AT including W30 as being 7042251 and the manual transmission 442 including W30 as 7042953 (must be typo, probably 7042253).

Well, looking at the other posts maybe the 2953 is correct.


John

 

Steve and 72xw30: Have a reference for the number you show?
2blu442: Thank You for the reference. 2953 is the right number.

Here are some of the references I have found:

1. "Oldsmobile Numbers Swap Meet Guide" shows four total numbers for 1972. It shows the 2251 as the 442 w/Auto and W-30. Shows the 2953 as all 442's w/Std Trans.

2. The Olds FAQ shows the 2251 on W-30 w/Auto and 2953 as W-30 w/Std.

3. Brothers Automotive site shows 2251 on 455 Cutlass models and 2953 on 442 and W-30's.

4. A Olds Carb list I found on the Net shows 2251's used on all 455's and 2953's used on all 442's and W-30's. http://www.teufert.net/carbs/olds.htm

You can see the confusion here. I am looking for opinions but more interested in backing those up with solid references. I have a 2251 but this is going on a 1 of 17 W-30.

Thanks in advance,
Mike

 

Pretty sure that 72xw30 Sam's W-30 was his father's car from new, so that's a good place to start.

Terry

 

Original cars are good references!

 

If you look inside your Oldsmobile Chassis Service Manual it will show that 7042953 came with engine codes of UL, UO, UN AND UD. UO, UL AND UN are (L77) engines. L77 is the W30 engine. UD is the 4 speed A body (Cutlass, Supreme or Wagon 4speed) code (L75) These 4 engine codes got the 7042953 carbs. Refer to page 6C-7 in Chassis Manual. 7042251 codes are UA, UB, US, UT engine codes

regards

 

Excellent! Thanks Mark, that was exactly the info and reference I was looking for. Looks like I need to take some pictures of my 2251 and put it up For Sale!

 

Source??? I don't understand where anyone would not *start* (and finish) with factory sources for information like this, as Mark has done. Especially when there is contradictory information out there.
And especially when this information is available to everyone free of charge at Wild About Cars. Wild About Cars is not a source, but has a library of *factory* sources.
This is exactly why the information is there, guys!

Wild About Cars. http://wildaboutcars.com. An information supersource, especially Oldsmobile. More Olds content than anywhere else on the internet and continuing to grow.
You'll find Chassis Service Manuals, Product Information Manuals (AKA Assembly Manuals), Inspector's Manuals, and other documents that will contain this and much much more.
Dealer Brochures, magazine ads and articles, and the Automotive History Preservation Society library growing daily.
Free to join, free to learn.

 

Mine was off the top of my head but this morning I checked the W-machine restoration guide and it said the same thing. Agreed the factory literature would be best. Original cars are great to go by as well but again some early 1970 W30 automatic cars had carbs with 4 speed numbers on them along with the 4 speed distributor.

 

I do have my dad's original car that's never been apart. It does have the 2953 carb.

Mike, if you need a 2953 lmk, I do have a few different date codes.

Cheers,

Sam

 

I recently spent $350+ for an absolutely beautiful complete restoration on a 2251 for my V Code Supreme, and it's never been fired. Looks like I'll be shopping for a 2953 as well....

Terry

 

Easy Kurt, not everyone knows about the wildasboutcars site. My info comes from my personal libray that I have collect for the last 25 years. I have many other manuals that are not even listed on their web site. Sometimes it is easier to ask a question due to time restraints between family life and work. Just my .02 cents worth. So if you folks want to ask a question, ask away. Almost made me feel like on ROP.
regards, ( I'm more into the racing part than car shows)

Free Engine build info
http://home.comcast.net/~wmachines/ENGINE/index.htm

 

I know, Mark. Its not so much about WAC as it is what information to use. If CO wants to be known as a knowledgeable source, then we need to prove we know better than to use secondary sources of information whenever possible. We have the resources, so we should use them. The last thing we should be doing is perpetuating bad information. That is no help to anyone.
(But I certainly will ease off if I'm creating those kinds of flashbacks for you!)

 

Kurt: Thanks for the reminder about WAC, there is a LOT of information there. I will make it a point to check it out again soon.

Sam: If you have a 2953 that you can't live without, let me know.

Mark: I'm checking out my hard copy Chassis Service Manual! Thanks again!

 

To add more to Mark's original info (and to confirm my research) and using the WAC website:

The Chassis Service Manual has a listing of carbs on page 6M-16 and 6M-38. 7042593 was used on engine codes UL, UN, UE and UD. Later editions of the manual I understand have the UO listed, I don't have one of those. I'd really like to see a copy. It would be great to get a photocopy of that page and put it up on WAC. It would tie up that question in the Service Manual.

On page 6C-7, all L-77 (W-30) engine codes are listed UL, UN and UO. This is also listed on page 0-3.

Taken from the Oldsmobile Inspection Guide on page 16; UO is the automatic (without A/C), UL is the M20 and UN is W37 (both std trans).

The Assembly Manual #411462 (Section 6-1) shows the Assy code UL, UN and UO that agrees with the Olds Inspection Guide.

Another one I found is in the Oldsmobile Performance Tips booklet. Page 15 shows 2593 as the carb number for the W-30.

Yet another is the NHRA Tech Specs which also calls out the 2593.

By the books, it seems the 2593 was the correct Q-jet for all W-30's (auto and std trans). The 2251 was used on 442's (non W-30). The 2251 has engine codes of UA and UB for a A body, neither of which are L-77.

Well, there you have it. Comments welcome.
Regards,
Mike

 

Sam, does your 2953 carb have a dashpot or electric solenoid for throttle control? The CSM says that it should have the solenoid.

My Oct 71 built W30 automatic has the dashpot. The wiring is all original and there is not wire there for a solenoid. I also don't have the original carb. Over 10 years ago my research, at that time, pointed toward th e 2251 as being the correct carb. But now this is in question.

With the ambiguity that exists between the application of these two carbs, I wonder if there was a mid production change or if both carbs were used during the 72 model year production run.

Warren

 

Warren,

My 72 W car was built Nov 4th of 1971. The car has the electric solenoid for throttle control.....NO dash pot.

Cheers,

Sam

 

the delco number 9 book also shows the 7042953 as being correct for all '72 442's.
there are 6 differences between a 953 and a 251.
in this numbering scheme, the 9 denotes a special application.


bill

 

Bill: Thanks for that info! I have received a copy of the page in the manual that shows definitive evidence that 7042953 was used exclusively on UL, UN, UE, UD and UO. I will be uploading that copy to WAC tonight, seemed like the best place for it...

 

I haven't been following this very carefully, so forgive me if I'm off base.

But which manual are you refering to? Chassis Service Manual? Always treat such information in the CSM as suspect. Sure, 9 times out of 10 it's correct. But sometimes it isn't. The CSMs were written and published in advance of actual production, and they did not go back and make corrections later if Engineering changed their mind during production -- or even before production started.

 

Just to add to what Brian said. Also consider the Chassis Service Manual Supplement. This is a thin manual that basically shows the differences from the previous year to current model year. I had the same problem tracking down the correct carb for my 71 W-30 4 speed. The supplement shows what I think are the correct carb numbers.

I scanned the following from the 72 supplement. I am not as familiar with the 72 engine codes so I will let those interested sort that out. Hope this information helps.

Don W

 

Don,

I now have the manual too that you shared that scanned image.

We have several areas in the CSM and the supplement that now agree.

Regards,
Mike

 

Mike
Off subject but does your 72 W30 have power or non power discs? I am trying to gather info on non power discs master cylinders on 71-72 W30s.

Don W

 

Don,

Here you go, mine is non power.

Regards,
Mike

 

Mike,
Thanks for taking the time to post the picture. Can you get the code on the half moon machined surface that I have circled in red. The code should be two letters stamped into the machined surface. ie RM. You will probably have to take a wire brush to the surface to clean rust off. Thanks again!!

Don W

 

I'd like to add a few remarks now that I've had a chance to study all the (factory) documentation.

Not quite, I think? I believe the 4 listed in the CSM are UL, UN, UE, and UD. Of note, these are all of the manual transmission 455s, two of which are L75 engines. But conspicuously absent is the UO auto L77. Not like it is listed elsewhere, it is not listed at all. So I think is safe to assume that it was an error in its omission and probably an original source for some of the confusion and misinformation. I have a "1972 Product Information" manual by Rochester Products that like the CSM is pre-production publication. Like the CSM, the UO is absent. (I can't find a factory source that has 7042251 for UO)
The source that Don listed fortunately adds the UO to the 7042953 carb.

Brian's point does have validity even in this case. There was an omission here with the early publications. Fairly simple in this case, but in other cases, the "facts" change during the year!

Helped tremendously! That is an early publication too, so it is interested that *it* had the UO included!

Bottom line is that none of the factory info had the carb for the UO engine misidentified. Just missing at times!

 

Mike, from the knowledge I have gained in 40 years of buying building and selling carburetors (and nobody knows everything) the correct carb for your 1972 W,-30 442 Olds is a 7042953. The D09 Delco carb breakdown book states that the 7042251 is 1972 Oldsmobile 455. It also states that the 7042953 is 1972 Oldsmobile 455, 442 I believe this to be factual because from 1969-1972 the 455 passenger (big car) carbs ended in 51. The Cutlass usually ended in 53 but not all W30s Now the reason I believe the 7042953 is correct comes from the fact that I have had numerous 7042251 Q-jets through the years indicating they were used on alot of cars from the factory and only (1) 7042953 in 40 years indicating they didn't put many on at the factory. How many 1972 W30 cars were built? Now did one of the 7042251 carbs find it's way on a W30 at the factory? Who knows? But the right carb number is 7042953. I sold one to a guy in Michigan in the 90s.

D09 book.