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DISCUSSION => Engine + Driveline => Topic started by: NitroRustlerDriver on November 29, 2011, 02:05:53 AM

Title: Thrust Bearing Ate My Crank
Post by: NitroRustlerDriver on November 29, 2011, 02:05:53 AM

Ugh, bad news. I went and checked play in the crank of my M42. Endplay is 0.070" and one side of the crank where the thrust bearing is is toast.

(http://img221.imageshack.us/img221/1949/p1010462b.jpg)

BIG gap.
(http://img443.imageshack.us/img443/2379/p1010463q.jpg)

This side looks great.
(http://img18.imageshack.us/img18/9296/p1010464w.jpg)

(http://img15.imageshack.us/img15/1157/p1010465e.jpg)

What are my options? Obviously I could find a used crank in good shape, but could the worn spot be welded and re-ground?

Title: Thrust Bearing Ate My Crank
Post by: DesktopDave on November 29, 2011, 07:15:28 AM

Sorry to hear the bad news...I'm sure it could be repaired, but likely it'd be more than finding a good used one.  I've heard a lot of doomsday advice about that bearing, but this is the first time I've seen one damage a crank.  There's a thread around here somewhere...IIRC an M50's full-radius bearing shells fit right in.

Title: Thrust Bearing Ate My Crank
Post by: colin86325 on November 29, 2011, 11:19:52 AM

I had to look at 3 different used cranks beofre I found one with acceptable wear.  You can have it welded up, ground, and then renitrided but I am not sure what that would cost.

Title: Thrust Bearing Ate My Crank
Post by: NitroRustlerDriver on November 29, 2011, 01:37:06 PM

Quote from: DesktopDave;108439

There's a thread around here somewhere...IIRC an M50's full-radius bearing shells fit right in.

New bearing sets have been updated and come with a full 360 bearing now.

Title: Thrust Bearing Ate My Crank
Post by: wazzu70 on November 29, 2011, 05:21:37 PM

You are correct that the new bearing sets have a full thrust bearing.

Bummer about the crank! I got lucky and mine was in decent condition. Guess you have to go stroker now :)

Do you still have your MG?

Title: Thrust Bearing Ate My Crank
Post by: NitroRustlerDriver on December 01, 2011, 01:56:20 AM

The MG is what the engine is going into. :D

http://www.r3vlimited.com/board/showthread.php?t=198933

And I found a used crank over on R3v. Hopefully it turns out to be good.