S&S Cycle Big Twin-Style Oil Pump Installation - Manual (Page 2)

2
See Picture 3. Marks in photo have been
darkened. They normally appear as light punch
marks.
CAUTION - Failure to align gear marks may
result in bind and possible damage to oil pump
or other engine parts.
3. Reassemble pump dry, without lubrication.
(Pump will be lubricated in final step.) Rotate
gears as preliminary check for bind, and to
confirm that drive gear keys are properly
installed in pump.
NOTE - If bind occurs, determine whether problem
is with supply or return gears by removing idler gear
from either side and rotating pump. When binding
gear is removed, pump will rotate freely. Problem
can usually be corrected by rotating gear 180
°
.
4. Apply 20W50 engine oil to oil pump driveshaft
and driveshaft bushing in crankcase. Install oil
pump in crankcase in normal fashion, placing
pump drive gear #33-4230 over driveshaft as
shaft is passed through bushing and into
crankcase gear compartment.
NOTE - A dab of Hylomar or other thin gasket
sealer in corners may be used to hold gaskets in
place if care is taken to avoid critical areas such
as oil passages and interior of oil pump. Otherwise
gaskets should be installed dry.
CAUTION - Gasket sealant may interfere with
engine lubrication if allowed to contaminate oil
pump or passages machined in crankcase.
Damage related to improper use of gasket
sealant will not be covered under warranty.
5. Install driveshaft gear key and snap ring, taking
care not to stretch or otherwise damage snap ring.
NOTE - Insure that drive shaft key and snap ring
are installed properly. If snap ring is installed
incorrectly, “sprung,” or otherwise damaged, it may
become dislodged or allow gear key to come out.
CAUTION - Loss of oil pump drive gear snap
ring or key will result in disengagement of oil
pump causing loss of oil pressure and
extensive engine damage.
6. Loosely install 2 ea. 1 ⁄
4
-20 x 1 1 ⁄
2
” top oil pump bolts,
followed by pump cover and 4 ea. 1 ⁄
4
-20 x 2 3 ⁄
4
”
mounting bolts. Do not tighten at this time.
Note - 1 ⁄
4
-24 bolts are supplied for use on 1948-
1978 H-D crankcases. Check thread fit by carefully
installing bolts in crankcase before final assembly.
Thread engagement should be smooth and free
of resistance.
CAUTION - Use of incorrect mounting bolts will
cause crankcase damage not covered under
warranty.
7. While turning oil pump drive gear to check
pump for binding, gradually tighten 4 ea. 2 3 ⁄
4
”
bolts in X-pattern to final spec. of 8-10 ft-lbs. If
pump binds, loosen screws and shift pump
slightly while rotating gears; pump should
operate smoothly if correctly aligned on
crankcase. Retighten bolts while turning
driveshaft to confirm bind-free pump operation.
Carefully tighten two remaining bolts with thin
box-end wrench.
8. Prime pump by removing oil pump check valve
ball assembly and injecting clean motor oil into
pump supply fitting while turning oil pump drive
gear. (A large plastic squeeze bottle works well
for priming pump.) Replace check ball, spring,
and cap after oil fills check valve cavity. Refer
to illustration and parts list near end of S&S Oil
Pump Instructions as needed.
Picture 3