D7 3T Crankshaft Grind

My after market catalogs only show 0.020 and 0.030" undersizes.
Check with Mike Mahler on here, he may be able to fix you up.

A review of the Cat numerical parts record "NPR" shows the 2f bearing were replace long ago by a newer design as follows:
original replacement florin tractor parts stock, Sacramento CA
Set 2f0491 6f1942 14
front 2f0484 6f1935 51
center2f0488 6f1937 14
inter 2f0486 6f1936 4
rear 2f0490 9f1938 1

If you search machinery trader they are othere sources.I believe the orignian 2f bearings were probably babbit, the 6f are aluminum. The aluminum bearings require more clearance, but that is built into the bearing. I would not suggest using a mixture of babbit and aluminum bearings.
Also if you would have a newer parts book it showns only the later 6f bearings.

Thanks for the info brian18a and Andrew. I have checked the 6F numbers with Tilly's here in Australia and they are all in stock including the rear seal. They do not do the kit but do the individual bearings. The other problem I have is the big end bearings listed as 7B1792 and 7B1793 in 0.050'' suiting a different connecting rod assembly in the parts book. Seems strange to have to buy a complete connecting rod to go 0.050'' undersize. Anyone know if 0.050'' undersize bearing shells are available to suit the original connecting rods on this engine.

what is the forging number of your rods, will tell what bearing would fit.

Forge number on the rod is 7B6225.

That forging no. gives rod assembly 7b6226 std, or 7b1930 0.050 us
The original 0.050 bearing consisted of two parts 7b1792 and 7b1793, probably babbit
The two parts were replaced by one of 6f1951, which was replaced by 4h5509, and that was replaced by 2m6501. The 4h5509 and 2m6501 are aluminum.

I suspect the reason for the rod change is a different bearing shell thickness.