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Slysc
05-03-2003, 11:34 AM
I just got my block back from the machine shop where it got bored&honed with torque plates,
aligned honed,
o-ringed.

I've got standard size Clevite main bearings and I put the top halfs in the block. Well oiled and assembly lubed. Then I laid my crank in the journals and it seemed real tight. If I spin it it turns with resistance. So I lifted it back out and looked at my bearings and the ends of the bearings are shiney like they are wearing.

Also, the bottom half of the end bearing that goes in the main cap has a anti-rotation notch that doesn't line up with the notch in the main cap. (??!!)

Are there different main bearings for different year blocks?

What kind of bearing to crank clearances should I be expecting for a newly refurbished lower end?

Vernon
05-03-2003, 11:58 AM
Dan, first the part about the notches not lineing up isn't right. If you don't have the top and bottom shell switched then there is a problem and you need to get the right bearing or you got the wrong one or two bottoms etc.

As for turning the crank, if I understand you correctly you haven't installed the caps yet, which makes sence because of the other problem. And now the exposed shell ends are rubbing, I think this is normal because you shouldn't be turning the crank without the caps on. The caps with the other half of the bearings will slightly crush the bearing shells together and the ends will push just a bit out away from the journals at the parting lines. One half of a never installed shell will still rub on the ends. Don't turn it anymore until you torque the caps down and have verifyed clearances with plasti-gauge or micrometers. Also it was line honed when new or more recently by your machinest with the caps installed and torqued. Slight clearances only line up well when this is done. Without the caps torqued down you shouldn't turn the crank or worry about the resistances. Only after it's assembled as will be ran should you try spinning the crank and it should turn freely.

Vernon