Main bearings bevel

[flyinlow]

Assembling a 440 /505  .The FSM states that the #1 main upper shell is beveled for timing chain oiling. The Cleveite bearings do not seam to have this. The bearings I removed from the 1978 motor home block did not have it either. Engine had a duel roller chain( for better Winnebago performance I guess). Do I need to bevel it?

I ordered the tall thrust bearings. Is beveling that bearing shell improve thrust surface oiling?

[Challenger340]

I know of no factory modification to the #1 Main Bearing to provide T/Chain Oiling.... Bearing throw off/leakage from the main/Cam are sufficient imo.

However, regarding Main Thrust lubrication...
Clevitte "V" designation main bearings, which are patterned after the old/defunct Vandervell Bearings.... employ a small 'chamfer' at the parting line to channel a very small amount pressurized Oil over on to the Thrust area to provide critical lubrication.

I believe the Clevitte Part number is MS1795V
or,
you may wish to file a very small 45* Oil feed into the Bearing Parting line yourself as seen here:

[John_Kunkel]

In some years and on some engines the factory parts book does show a different part number for the #1 main bearing than for #2, #4 and #5.

[flyinlow]

Thanks for the information.

Put a small bevel on the thrust bearing.