Hi all - after 30+ years I have finally convinced dad to fully restore his 1957 GMC 630 tractor. It has 26,000 original miles on it and he bought it from the military in the early 1970's and used it around the ranch to shuttle trailers around and haul dozers and the like in the area.
The thing started up after bypassing the gas tank within 20 seconds after sitting for 37 years.... 37 years. It even had good coolant in it. We were all shocked. Anyway, now comes the challenge. Parts for the motor. I can't seem to find any for the big 503.
Anyone have any good insights on this? Right now the immediate need is for intake/exhaust manifold gaskets; there is a leak. He is 85 now and really doesn't want to make his own.
From the pics you can see the last time it was registered was in 1986.
1931 one ton stake bed 1942 Military bomb service truck (converted to fire truck - not pictured) 1946 Chev half ton PU (Not pictured) 1948 Chev 3100 half ton PU 1956 Chev Bel Air 1946 John Deere H
I don't have any parts, but I do have a GMC Master Parts Book that covers your truck. If I can help with information please let me know. Below shows the GM part numbers for your gasket. Perhaps an internet search using these part numbers would turnup something.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
Parts for the 503 are just about nonexistent. I was able to find an upper engine set for a 54 GMC 503 at an obsolete parts vendor in Canada several years ago. It was the last one they had in stock, and it got used during replacement of a leaky head gasket. Making those exhaust gaskets might be your only option. Ed Pruss, a long term member here, owns that truck. I'd suggest sending him a private message to see if he can advise you n parts sources. Other similar GMC engines were made on the same basic design, including a 426 cubic inch version, and a couple of other sizes.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I'm going to move this thread to the “Big Bolt” forum in hopes of reaching a bigger audience for this truck. There are plenty of BB experts on this forum that I’m sure can at least point the OP in the right direction.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum
Thanks for the help. I thought this one was going to be a struggle; I just did not know how much. Makes one think we should just pull the engine and put something more modern in... like a Cummins diesel. I hate to do that because this thing is a time capsule.
1931 one ton stake bed 1942 Military bomb service truck (converted to fire truck - not pictured) 1946 Chev half ton PU (Not pictured) 1948 Chev 3100 half ton PU 1956 Chev Bel Air 1946 John Deere H
With only 26K miles, that one is barely broken in. I'd strongly suggest keeping it, and doing whatever it takes to get it back into running shape. Unless the engine is seized up, it's highly unlikely it will need anything more than a good tuneup and maybe a carburetor rebuild to put it back into good condition. One of the really oddball features of those engines was the bolt-on cylinder assembly- - - - -worn out cylinders could be removed and replaced instead of boring the block and fitting new pistons, since the cylinders and crankcase were bolted together, not cast as a single piece. Like most other GMC engines, they were built to be reconditioned repeatedly. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Engine definitely not seized. Runs great and solid. This one is a little odd though; it has a triple carb setup. (didn't look too closely to see much about that yet - who made the manifold and carbs - as it runs solid). According to Dad it came that way from the military when he bought it.
The exhaust leak just wants to put you to sleep in the cab... which is a problem so we don't want to try and run it long without a new gasket. It also gets about 4 miles to the gallon with that setup so probably not going on any long distance highway runs.
1931 one ton stake bed 1942 Military bomb service truck (converted to fire truck - not pictured) 1946 Chev half ton PU (Not pictured) 1948 Chev 3100 half ton PU 1956 Chev Bel Air 1946 John Deere H
This one is a little odd though; it has a triple carb setup. (didn't look too closely to see much about that yet - who made the manifold and carbs - as it runs solid). According to Dad it came that way from the military when he bought it.
Not to dispute what your Dad said, but I doubt if it came directly from the Military to him with triple carburetors. From my experience with military stuff, they were dirt simple and as cheap as possible. I really doubt that the military would have coughed up the funds for a 3-carb setup.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Do yourself a BIG favor and put a solid piece of metal under two of those carbs. That way you can impress the people who don't know any better, increase the gas mileage exponentially, and pull loads as well as (or better than) you can with an over-carbureted engine. The proper carb was a fairly large single 2 barrel with a rectangular footprint. Ed Pruss lives close to the Denver area, and he's for a good running 54 GMC 630 with a 503. It started out life as a fire truck. I'm pretty sure he can give you the straight scoop on what works on that engine. It's the same one I drove from middle Tennessee to Kansas City a few years ago after Ed had problems on his way home from where he bought it in Cullman Alabama. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Civilian '57 GMC 503 had three carb options when they left the factory, a 2 barrel Zenith, a 2 barrel Holley and a 4 barrel Holley.
Last edited by Bill Hanlon; 12/14/20232:23 AM.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
4 MPG is a little heavy if you were bobtailing. If that was loaded it's par for the course.
I drove a Cornbinder 18-wheel truck-and-trailer loaded with hay back in the day. It had a 350 HP, 1090cu. in. Hall-Scott 6 with a 5X3 trans. It got about 3.5-4.0 for a 150 mile trip, pulling a 3,000 ft. pass. It had dual ignition, OHC, twin updraft carbs the size of coffee cans, two-piece exhaust manifold and very large fuel tanks.
The other truck, a Freightliner with a 220 Cummins and a 10-speed Fuller got about 5.5mpg. It was way slower. Being senior driver I got the I-H and got home a half hour earlier.
1951 3800 1-ton "Earning its keep from the get-go" In the DITY Gallery 1962 261 (w/cam, Fenton headers, 2 carbs, MSD ign.), SM420 & Brown-Lipe 6231A 3spd aux. trans, stock axles & brakes. Owned since 1971.
jaycoop, Is this the Olson's in Washington state vendor you are suggesting??? I checked for contact info for "Gasket City in Ontario, CAN" and found this Contact Us page. Is that the correct info??? The "Gasket City" web page info doesn't seem to have been updated in a long time.
I hope these links may be helpful???
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
Engine definitely not seized. Runs great and solid. This one is a little odd though; it has a triple carb setup. (didn't look too closely to see much about that yet - who made the manifold and carbs - as it runs solid). According to Dad it came that way from the military when he bought it.
The exhaust leak just wants to put you to sleep in the cab... which is a problem so we don't want to try and run it long without a new gasket. It also gets about 4 miles to the gallon with that setup so probably not going on any long distance highway runs.
I would love to see a picture of this setup, not that I would use it but I bet it looks different.
~ Craig 1958 Viking 4400 "The Book of Thor" Read the story in the DITY 1960 Chevrolet C10 "A Family Heirloom" Follow the story in the DITY Gallery '59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting)
Come Bleed or Blister, something has got to give!!! | Living life in the SLOW lane
jaycoop, Is this the Olson's in Washington state vendor you are suggesting??? I checked for contact info for "Gasket City in Ontario, CAN" and found this Contact Us page. Is that the correct info??? The "Gasket City" web page info doesn't seem to have been updated in a long time.
When I was working on the 503 that broke down on Ed Pruss in middle Tennessee a few years ago, I got the last head gasket set that Gasket City had in stock. They also had a single head gasket, which I didn't choose to buy. I ended up doing a temporary fix on a leaky head gasket with water glass (Sodium Silicate) to get the rig to Kansas City, where Ed picked it up and drove it on to Denver. I believe he used the gasket set when he did a more thorough fix after getting the truck home. That happened a year or two pre-Covid. Jerry
Last edited by Peggy M; 01/18/20246:24 PM.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Yes. Gdads51, thank you. Those are the correct sites and contact information. Al Lambert of Gasket City apparently does not keep up on his website, but he is still active. Saw him at Hershey this past fall. He has an amazing collection of early NOS gaskets for sale. The advantage of Olson's is that they can reproduce any gasket using modern materials - and they have patterns for most. Neither option is reasonably priced, but these gaskets do come up now and then at a bargain price, at Hershey and like swap meets.
