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May 4th, 2018, 09:58 PM

68ac442

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New member carb question

I’m going to collect a barnfind 68 442 tomorrow. It is partially disassembled. I need to know the correct carb/casting number for a 1968 olds 442 with 455 and automatic as there are abou 6 carbs in the barn thanks for any help
jr

May 5th, 2018, 03:39 AM

bccan

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Location: West Hartford, CT

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JR- Someone will probably come through w/ some carb #’s but since you are on a time line be advised that a 68 442 should have a 400 in it. Only full size cars & Hurst Olds would have 455.

May 5th, 2018, 03:47 AM

tru-blue 442

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Location: Marble Falls TX

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Welcome. 7028251 is for an auto. 7028253 is for a manual. Note that it should have a 400 c.i. engine in it if it's a 442. Unless it's a Hurst Olds, then it got a 455.

Look for #'s on the timing shelf, above the water pump, below the thermostat housing.
A 400 would be 396026G a 455 would be 396021F. If he has a 7040257 carb in
his stash, I would be interested. If you can record the carb #'s when you go, we can
tell your their applications. Good luck and take your camera!

May 5th, 2018, 03:56 AM

rob1960

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7028251 is the common big block carb for '68. It was used on everything except Toros. Stick shift 442s used a "253" carb but there seems to be some controversy on that & '68 W30s used a "254" carb. Like bccan said a '68 442 would have only had a "G" block 400 in it.

May 5th, 2018, 05:43 AM

joe_padavano

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Location: Northern VA

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Quote:

Originally Posted by rob1960

There's no controversy. The factory published tech bulletins that clearly spelled out the carb number use. Yes, I realize that the first chart has a typo - the 1968 '251 carb usage should be "400-455", not "400-425". The second document clearly spells out that the '254 carb was used on 1968 W-30 motors from engine unit number 8342491 and up.

May 5th, 2018, 06:08 AM

68ac442

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Thanks for the info! I have been rebuilding chevys for over 20 years, but this will be my 1st olds. Had assumed the engine on the stand was the original, which is the 396021f, the owner is the daughter, her dad bought it in 1980, and it was partly dissassembled years ago and is stashed around the barn. Dad is no longer around so I am trying to collect all the original parts which I believe are there from what I can see so far. I told her I would do my best to only take the parts that belong to the car. Now I have to figure out which motor is correct. I believe there were 2 other olds engines. On Thursday I didnt know where the vim stamp was on the block, so I should be able to figure it out.

May 5th, 2018, 06:12 AM

joe_padavano

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Quote:

Originally Posted by 68ac442

The block will have a VIN derivative stamp. I can pretty much guarantee it does not match the VIN of the car. The G-block 400 motors that came stock in these cars were not the best design (long stroke, tiny bore). When they got blown up, they were frequently replaced with a 455.

May 5th, 2018, 07:15 AM

68ac442

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Thanks, I’m am confident the original motor is there, based on the interior this is a low mile car, it may be one of the bare blocks, but this guy even kept original spark plug wires

May 5th, 2018, 07:07 PM

68ac442

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Well most of the beast made it home today, i ponied up some extra money and brought home parts I was unsure of. I am going to be needing some help with parts id as I unload and catalog it. I did find the vin stamped g block, but as described must have spun bearings or something, it’s mostly a short block, couple of the rods and pistons were out, so I got the 455 I originally thought was the original motor too, it looks to have had some level of fresh rebuild and he had an electric motor rigged to the engine stand to prime oil through it. I’ll have to disassemble it to see what all has been done. thanks again for the help!