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| | | | Joined: Jun 2018 Posts: 52 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2018 Posts: 52 | According to the engine ID my 228 came new with .010 main and .010 rod bearings. I want to slap a new set in and wonder if anyone can decipher the bearings I pulled out? Google Web draws a blank. The numbers are as follows :
Mains
GMMA 6056 297D0
6057 296X0
6423 256D0
6059 216V0
Rods
GMMA 6055 T0
6055 T0
6055 U0
6055 U0
6055 S0
6055 U0 | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 |
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Feb 2004 Posts: 29,828 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,828 | Use a micrometer. A dial caliper (or even a digital) is only good for a SWAG. You need to make measurements of the journals you can reach for wear and taper down to a tolerance of .0005" or so. Unless the crankshaft is out of the block, it's difficult to get that accuracy on the main bearings. Drop me a PM and I can give you the exact measurements you're looking for.
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: Jun 2018 Posts: 52 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2018 Posts: 52 | Engine is in the truck and I don't plan on pulling the crank. I checked the clearances and they are acceptable but definitely on the loose side. The head is out being redone and I want to do quickie rings and bearings while it's off. I don't know much about the truck. Supposedly it was sitting since the '80s. | | | | | Joined: Feb 2004 Posts: 29,828 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,828 | Like the Sun test equipment slogan used to say- - - -"We Test- - - -Not Guess!"
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: Jul 2003 Posts: 132 'Bolter | | 'Bolter Joined: Jul 2003 Posts: 132 | I agree with the need to measure. Also, every undersize bearing shell I've seen was so stamped. Std size are not so marked. I have also never encountered a GMC with factory undersizes. Maybe a rebuilder??? | | |
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