twilightblue28A

Ebay is advertising a NOS quadrajet for a 455/365 442. I asked for the part number and was provided with PN 7040251 with a Julian date "1909" is the carb correct for a 1970 442/365 automatic or manual? Also, can someone explain decoding the Julian codes. BTY asking price Is $700.00.
As usual I will appreciate your help. Thanks, harry

MDchanic

1970:

F85 455 Eng. 4 BC S.T. w/O.A.I. 7041326
4400 AT OAI 7041340
4400 A.T. exc. O.A.I. 7041327
4400 455 4 BC S.T. exc. O.A.I. 7036931


- Eric

2blu442

Eric, my experience is different than the numbers you posted.

Harry, I believe that is correct for an automatic in a 442, but that same code was used on other applications in 1970. I've got a manual transmission in mine and the correct number for that is 7040253. The $700 price tag seems very high to me. The 7040251 is a fairly common carburetor. The manual transmission or the W car carbs are much more rare and might be in that price range. Others will speak up but I'd pass on it at that price. John

MDchanic

I'm not saying that no other carburetors would work, John, or that the numbers weren't superseded, but if Harry is looking for the exact right part number for a 1970 442, then these are the part numbers listed in the Parts Manual, and, in fact, 7040251 is not listed anywhere in the '72 or '75 Parts Manuals at all.

The notorious FAQ lists 7040251 as the correct carburetor for the '70 455 Cutlass, but not for any of the 442 variations, which are listed as:
7040253 — 442 MT
7040256 — W-30 MT
7040258 — W-30 AT
7040257 — W-33, 442 AT


- Eric

tdhill01

Harry, the correct carb should be 7040257 for the automatic 442 - not the w30 model. The date break-down for "1909": The first three digits represent the number of days (190th day) and the last digit is the year (1969). According to "1909" the carb was built the 190th day of 1969. I am not 100% sure but I do believe someone will chime in if I am wrong.

I also would not spend that type of money for a 7040251 carb.

joe_padavano

Eric,

Don't confuse part numbers with carb numbers. The CSM lists the carb numbers, which are the stamped numbers on the carb body. In this case, the FAQ is correct.

twilightblue28A

First, I want to apologize for duplicating my original post. I bought a new "smartphone" and I'm experiencing a learning curve. Sorry for any confusion this may have caused.
Second, the carburetor that is for sale on Ebay is described as NOS, for a 455/365 engine, and with a Julian code i909 which has since been defined. If it is a NOS does that justify the cost of $700.00 or still to expensive.
Third, In order to clarify conflicting part numbers for the same car I propose the following: Hypothetically, it is 1970. I just drove out of the Oldsmobile dealer with a new 1970 442/365 with automatic transmission and a W25 OAI hood. What quadrajet carburetor part number is installed on the car?
Finally,
thank you for providing the year for the Julian date given. Where do I go for Julian dates and their conversions? Is there a conversion chart on our site?


Thank you again for your assistance. Harry

joe_padavano

If it was a 442, it came with a 7040257 carb. If it was a Cutlass, Supreme, or full size, it came with 7040251. That's exactly what the CSM list says - there are no conflicting carb numbers. W25 or not didn't matter.

twilightblue28A

Joe,


Thank you for simplifying the information requested. Harry

Fun71

Quadrajetpower's web site lists a 7040251 for $325:

https://www.quadrajetpower.com/onlin...251/p/73747234

MDchanic

Thanks for that information Joe - I never knew that those very similar numbers were, in fact, completely different.

- Eric

zeeke

$700 seems a bit high. Be careful with carbs. You never know whats inside them. Do your research and compare pictures as well. I read through Cliff Ruggles book on Quadrajets. Lots of good info.

tru-blue 442

I have been hunting a 7040257 for a while. The are elusive...

joesw31

These carburetors were very expensive new from the dealers. I recall cost being in excess of $400.00 back in the 1980's. So, maybe the $700.00 is not totally out of line if the carb is NOS (Never used). Infact, a lot of things were very expensive new from the dealers. I recall the OAI hood pins being over $50.00 a piece at cost.