Bearing Tolerances
#1
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Joined: Sep 2001
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From: Las Vegas, NV
Can you mix standard size bearings and .001 undersize bearings to obtain desired clearances??? Is there a location top/bottom where it is better to place the standard or undesize bearing?
Thanks..
Thanks..
#2
Yes. I was told to put the standards on the top of the rod (piston side) (if you are talking rods. If mains, I guess standards on the bottom (cap side). If you are too tight on the rods and need some 1x bearings, I have a set.
#4
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Joined: Jun 2004
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From: Omaha, Nebraska. Boat on the Mighty Mo! Longest river in the USA!
Do I understand this correctly, you want use different size on the same journal?
Why don't you get it machined
to the tolerance you are trying to get to?
Why don't you get it machined
to the tolerance you are trying to get to?
#5
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Joined: Oct 2005
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From: Waldorf, Md
TM,
Here is a qoute from Clevite's web site:
"If clearance adjustments need to be made, use either an extra clearance part for more clearance or an undersize part for less clearance. It is permissible to mix sizes if less than .001" adjustment in clearance is desired. When mixing sizes for a select fitting: a) never mix parts having more than .0005" difference in wall size; b) and always install the thickest wall shell in the upper position if installing a rod bearing or the lower position if installing a main bearing. "
Big Jim, Once a crankshaft has been reground, it is VERY difficult to take just a thousanth off it.
Hope this helps,
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
Here is a qoute from Clevite's web site:
"If clearance adjustments need to be made, use either an extra clearance part for more clearance or an undersize part for less clearance. It is permissible to mix sizes if less than .001" adjustment in clearance is desired. When mixing sizes for a select fitting: a) never mix parts having more than .0005" difference in wall size; b) and always install the thickest wall shell in the upper position if installing a rod bearing or the lower position if installing a main bearing. "
Big Jim, Once a crankshaft has been reground, it is VERY difficult to take just a thousanth off it.
Hope this helps,
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
#6
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From: Las Vegas, NV
Thanks Bill...very helpful...I'll have to check out there website.
I'm just trying to get my mains from .003 to .025 or maybe to .002...I'm not sure which would be best yet.
I haven't checked my rods yet, but I may need to do the same there as well...
I'm just trying to get my mains from .003 to .025 or maybe to .002...I'm not sure which would be best yet.
I haven't checked my rods yet, but I may need to do the same there as well...
#7
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From: sint maarten
how are you making these measurements ? if you are using plastigage you haven't got anything like the resolution you want and if you are using a dial bore gage and a mic, you want to make sure that you get the stretch " as installed" or the crush will be wrong and so will your math. time spent here doing it right is money saved later fixing it.




