81 – Model 638 Cam Case Breather

The following change in cam case breathers is recommended
on all model 638 motors to reduce breather losses to a
minimum.

1. Remove oil pump and cam case cover.
2. Tap out center hole between crankcase and cam case
   with 1/4″ pipe tap. Plug hole with VF2285 plug.
   Stake plug in. (See Fig. 2).
3. Drill out and tap 7/16″ – 24 the breather hole in
   cam case cover. (See Fig. 2).
4. Screw in and lock tight with nut, breather inlet
   nipple.
5. After tapping cam case cover, be sure there are no
   burrs on the outside face which would prevent proper
   operation of the breather disc.
6. Replace cam case cover and oil pump.
7. Change breather tube to 41497.
   

Parts required are as follows:
1 – 40718 Breather inlet nipple.
1 – 24B17 Lock nut.
1 – VF2285 Plug
1 – 41497 Breather tube.
The necessary parts to make this installation on all Indian
Sport Scouts that have been shipped to date, will be mailed
you without charge.