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Triumph TR6 - Crankshaft Bearings

Hello Guys,
While waiting for my new oil pump I pulled out the connecting rod bearings and they look ok top and bottom halfs, the main bearings are worn showing some copper on the bottom halfs.I'm replacing them all but not sure how to measure what I need..standard or ???.
I have no visible thrust washer movement but I will replace them also while in there..I've learned from my friend Bill to watch out for thrust washers !!
I removed them and they look ok but again do I just order the standard size ???
Thanks
Charlie
Charlie Ballard

Hi,
Buy at your local autostore plastigauge and proceed as written in Haynes manual. If your bearing are score with marks, may be the crank need polishing.
JGC
Jean G. Catford

Charlie--I would consider replacing the OEM steel rear thrust washer (TW) with a bronze alloy version. See http://users.arczip.com/zntech/tr6.html
for specifics. I just put a rear one in this month.

As far as what size to use, mic the better of the 2 TW's, reinstall them (with the good one on the front side) and measure your endfloat. Subtract 0.006" (or 0.005" if you want to allow for a minor amount of initial bedding-in) and the mic'd thickness from the endfloat measurement. The result is the thickness of the new rear TW.

Rick O.
Rick Orthen

Charlie - If you want to replace the bearings for the con-rod big ends or the crank main bearings, take a micrometer and measure the diameters. Compare your measurements to the stock original dimensions listed in the owner's manual or the parts lists. Your crank diameters that you measure are either stock or 0.010" increments smaller. From that, you can order the replacement bearings. You might want to talk to Dave at Roadster Factory after 12 noon about this if you feel you need to. Mention my name and say hello to Dave from me.

Don Elliott, 1958 TR3A
Don Elliott

Charlie
The bearing size is normally stamped on the back of the shell, if there is nothing on it usually means they are standard.
It sounds as though the big end bearings have been replaced in the past and not the mains by the wear pattern you describe.
The comment about the bearing size also applies to the thrusts
Ron
R. Algie

Hi Guys,
Ron....The only thing stamped on them is a 4 digit part # but there is no .10 or such indicating thickness. I'm told if that's the case then they are standard size and I should install new standard size providing the crank measurements are within spec..I'll check that hopefully the next day or so.
Rick O...I'm going to order the alloy washer and I understand I can use the old good one on the front side ( towards the fan ) and the new alloy on the transmission side (this being the load bearing TW?) and of course calculating the new thickness per your note above.
Thanks
Charlie
Charlie Ballard

Charlie--Yup, the alloy TW goes to the flywheel side. I re-read my instructions and they are confusing. Here's what I should have written:

Alloy (rear) TW thickness = (Existing Endfloat - 0.005) + Used (front) TW thickness.

The one I ordered was 0.098" thick and it could have passed a jewelry! Remember too that the oil grooves face away from each other on the install.

Rick O.
Rick Orthen

Charlie
You have mail
Rick C
Rick Crawford

This thread was discussed between 25/03/2004 and 29/03/2004

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