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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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| | | | Joined: Oct 2017 Posts: 32 'Bolter | | 'Bolter Joined: Oct 2017 Posts: 32 | Hello I have a GMC 302 engine Number 302187583. Could some one help me dating the engine, also what is the factory standing crank big end bearing and mains bearing size., and where can i get new shells.
Many Thanks Howard | | | | | Joined: May 2015 Posts: 11,004 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,004 | Here's some info that could help you date your engine. Link
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 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. | | | | | Joined: Feb 2004 Posts: 29,751 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,751 | Have you tried flowers, candy, and soft music?  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!
| | | | | Joined: May 2015 Posts: 11,004 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,004 | Have you tried flowers, candy, and soft music? Jerry 
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 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. | | | | | Joined: Feb 2004 Posts: 29,751 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,751 | According to my Federal-Mogul specification book, the 248, 270, and 302 engines all share the same connecting rod and main bearing sizes.
Rod bearings: Federal-Mogul part number 1905 CP Standard shaft diameter is 2.3110" - 2.3120"
Main bearings 1954-55: 697 M 1956-63 engines: 4030 M
Main bearings have four different diameters, like 216 and 235 Chevy engines.
#1: 2.6835 - 2.6845
#2: 2.7145 - 2.7155
#3: 2.7455 - 2.7465
#4: 2.7765 - 2.7775
Earlier manufacture date 228, 248. 256, and 270 engines have the same shaft sizes, but they use different part number bearings for some reason.
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!
| | | | | Joined: Dec 2017 Posts: 1,652 'Bolter | | 'Bolter Joined: Dec 2017 Posts: 1,652 |
Mike
| | | | | Joined: Feb 2004 Posts: 29,751 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,751 | Orchids and Barry White albums always worked well for me!
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!
| | | | | Joined: May 2006 Posts: 934 'Bolter | | 'Bolter Joined: May 2006 Posts: 934 | Good to know. All along I thought a bouquet of pushrods, an oil bath, and gift wrapped main seals would have caught your fancy.
Last edited by tom moore; 06/13/2021 10:15 AM.
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