Crankshaft thrust washers
Posted: Tue Apr 21, 2009 6:16 pm
I have here an unused crankshaft for a 1098 engine that came in an original BMC spares cardboard box, still coated in hard brown anti-rust gunk. I've measured the bearing journal diameters and compared them to the figures in the manual, and ascertained that they have been reground to -20 thou.
As best as I can measure it without a suitable internal micrometer, the distance between the central thrust faces is 1.257". The manual doesn't quote a standard figure for that dimension and I don't have an un-reground crankshaft to hand for comparison. I'm guessing it is likely to be 1.25" because the bearing diameters are all common fractions.
If I'm right, that would mean the thrust faces have each had about 3.5 thou removed. Does that sound right to you? ESM list +3 thou thrust washers but they are currently out of stock. Bull Motif only list standard ones.
While I'm here, does anyone happen to have a spare pair of -20 main bearing shells they'd be willing to sell me? The crankshaft came with four but obviously you need six for a full set.
Incidentally, the counterweights have machining marks very similar to those discussed in the "Balanced crank?" thread.
As best as I can measure it without a suitable internal micrometer, the distance between the central thrust faces is 1.257". The manual doesn't quote a standard figure for that dimension and I don't have an un-reground crankshaft to hand for comparison. I'm guessing it is likely to be 1.25" because the bearing diameters are all common fractions.
If I'm right, that would mean the thrust faces have each had about 3.5 thou removed. Does that sound right to you? ESM list +3 thou thrust washers but they are currently out of stock. Bull Motif only list standard ones.
While I'm here, does anyone happen to have a spare pair of -20 main bearing shells they'd be willing to sell me? The crankshaft came with four but obviously you need six for a full set.
Incidentally, the counterweights have machining marks very similar to those discussed in the "Balanced crank?" thread.
