S&S Cycle Super Stock and Special Application Crankcases for 1936-99 Big Twin Engines User Manual
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5
Restricted oil flow may result in extensive engine damage not covered under warranty.
A- Gear cavity vent passage
Location: Hole A. See Pictures 3, 4, 5 & 6.
Hardware: 50-8115 hose fitting or 31-2018 oil line fitting. See Line Drawings on last page, items 35 and 39.
Function: Vents gear cavity. Equalizes pressure in gear case and oil tank. Is also connected to primary chain case in 1965 - 1984 models with
dry clutch and engine-supplied primary chain oiling.
CAUTION
Picture 3
Picture 4
Picture 5
Picture 6
C
A
E
A
B
C
E
F
G
A
B
C
E
F
G
D
H
B
A
C
D
E
F
G
Installation: 1936 - 1969
1- Install fitting 31-2018 in hole A.
2- Connect oil vent line from oil tank to fitting.
3- Install t-fitting (H-D® #63580-66A) if stock 1965-1969 primary chaincase oiling system with dry clutch is desired. See Picture 7.
Installation: 1970 - present
1- Install fitting 50-8115 in hole A.
2- Connect oil line vent from oil tank to fitting.
3- Install t-fitting (H-D® #63580-66A) if stock 1965-early 1984 dry clutch and engine-supplied primary chaincase oiling system are desired.
See Picture 7.
* All reference to Harley-Davidson® part
numbers is for identification purposes only. We
in no way are implying that any of S&S® Cycle’s
products are original equipment parts or that
they are equivalent to the corresponding Harley-
Davidson® part number shown.
Picture 7