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quatrini
12-11-2013, 11:48 AM
okay guys me engine build is coming along, having the cylinders bored 30 over next week and getting the deck resurfaced. once thats done, i am going to be re assembling the engine. however i was told that the rear main journal is .010 undersize from the rest. the main bearings i bought are "clevite 77" and are stock replacements. they are not in numerical order that i can tell. my only concern is how will i tell which one goes where? im going to plastigage them obviously, but im just trying to avoid damaging the new bearings and also not mix anything up because im putting a good amount of money into this motor, nothing serious, but expensive for my budget. i dont want to turn it over the first time to a severe knock.

820
12-11-2013, 01:20 PM
They should be marked on the back of the bearing

bowez
12-11-2013, 06:06 PM
Bearing should have PN on them 1 thrust, and 2 bearing with one PN and one different.

Though I'm curious what the opinion is on turning all the journals to the same size?

Mike8675309
12-12-2013, 11:02 AM
Bearing should have PN on them 1 thrust, and 2 bearing with one PN and one different.

Though I'm curious what the opinion is on turning all the journals to the same size?

Crank journals is nitrite hardened. Unless you already had to turn the crank and use oversize bearings I don't think you want to turn it just so all journals are even. Especially when proper bearings are readily available. King even has our proper main bearings with various oversizes. Stock size is #MB4052SI

quatrini
12-12-2013, 12:29 PM
Okay thanks guys. I haven't opened my package of bearings yet. Obviously the thrust bearing looks completely different then the others, but if I understand correctly the undersize journal will have pn engraved on the back of the bearing? I'm sure I can figure it out since there will be two others to compare markings to, but I am extremely cautious. I'll be posting a build thread in about two weeks I'd appreciate everyones advice and insight on the build.