Triumph Repair: GT-6 main bearings, merritt island florida, glacier bearing

Question
Dear Howard,
  I am rebuilding my GT-6 Mk1  engine and have received the wrong main bearings twice. First from Victoria British, then from e-bay where i ordered some Glacier bearing that appeared to be of uniform width! The first set had two pair that were wider for the end journals. It's my understanding that the crankshaft was enlarged from KC 5000 on. The engine # is KD11800E, the bearing i am replacing are all uniform width. Can you help me find the proper bearings from someone? Thanks in advance for your help! Terry Andrews  Merritt Island, Florida

Answer
Hi Terry,

Many replacement bearings are not as wide as the original bearings. As long as the tab fits and they are the correct size and the oil holes are correct they can be used. Some bearing manufactures narrow the bearings a little because on under size bearings (.010", .020", .030" etc)when a crank grinder grinds the shaft down they often increase the side radius which leaves a more narrow flat surface for the bearing.

Be sure to mike the shaft for out of round and to confirm that the shaft grinder got the specs correct. Even the best make mistakes and if you stick new bearings in and don't check it you can end up with a locked up engine very quickly.

It is more important on a crank that was not turned as they can ware egg shape but look good.

Also be sure to Plasti-gauge every bearing.

If you use "White Lube" to lube bearings don't put too much on as you can destroy a crank and bearings as I seen a mechanic in one dealership do. Read my tech tip on engine rebuild on my web site.  http://mg-tri-jag.net/Preamble.htm

Howard