Teh length/diameter ratio is 2/3 to 3/2, the smaller figure is more relative to modern designs and can help reduce oil whirl. The top clearance is 0.5mm, this is sufficiently large to allow for large quantites of oil flow to aid cooling. No oil ways are provided other than a small amount of metal washed away at the inlt oil ports.
Maximum oil temperature is 83'C
White metal thickness 0.25 to 0.5mm, the thicker this layer the greater the ability to cope with dirt absorbtion. Thicker white metal is required for gun metal backed bearings due to the possibility of copper pick up should the white metal run. The white metal adheres better to the steel and provides better rigidity.
Typical white metal 85% tin, 8.5% Antimony, 6% copper.
An antisiphon device prevents all the oil leaving bearing if there is a failure of oil supply
Dummy bearings must be introduced to allow removal of lower bearing for inspection