The idler gear mounts on a double row, tapered roller bearing which, in turn, is supported on a stationary hub. A
hollow pin serves a two-fold purpose; first, as a locating dowel it prevents the idler gear hub from rotating and, second,
the hollow pin conducts oil under pressure from an oil gallery in the cylinder block through a passage in the gear hub to
the roller bearing inner races.
The inner races of the idler gear bearing are pressed onto the gear hub and, therefore, do not rotate since the hub is
doweled to the end plate and bolted to the cylinder block and also bolted to the flywheel housing. A spacer separates the
two bearing inner races.
The bearing outer race has a light press fit in the idler gear and is held against a flanged lip inside the idler gear on
one side and by a retainer secured tightly with six bolts on the other side.
A right-hand helix gear with "L" timing marks is provided for left hand rotation engines, and a left-hand helix gear with
"R" timing marks is provided for right-hand rotation engines, see paragraph 3-27.
An idler gear hole spacer (dummy hub) is used on the side opposite the idler gear. NO gasket is used between the
idler gear hub or dummy hub and the flywheel housing. The flywheel housing bears against the inner races of the idler
gear bearing and also against the dummy hub. Three self-locking bolts and steel washers are used to attach the flywheel
housing at the idler gear and dummy hub locations. The washers seat in 7/8" spot faces at the flywheel housing
attaching bolt holes, thus preventing oil leakage at these locations.