Service manual

8
A. Wrap masking tape around .203" (
13
⁄16") drill bit .375"
(
3
⁄8") from drill point to use as depth guide. CAREFULLY
enlarge hole in Picture 18. Using tape as guide, drill
hole .375" (
3
⁄8") deep. See Pictures 18 and 19.
NOTE - Drill bit size is very close to hole size and may tend to
distort hole if drill is not steadied.
CAUTION - Distorting hole may cause poor thread fit after
hole is tapped.
B. Using
1
⁄4 -20 tap, CAREFULLY tap hole deep enough
for
1
⁄4 -20 allen head set screw supplied in kit to bottom
out with screw head .125" to .150" below gear cover
gasket surface. See Pictures 20 and 21. Remove
tap periodically and install set screw to check depth.
NOTE - Do not tap hole so deep that screw blocks tappet screen
oil feed passage, inadvertently restricting oil supply to lifters
and cylinder heads.
CAUTION - Restricting oil supply to cylinder heads may
cause extensive engine damage.
C. Remove oil plug and lifter screen filter assembly. Blow
air in top end supply hole directly below top right pump
mounting bolt hole to remove chips and ensure that
passage is not blocked. See Picture 22.
WARNING - Compressed air and particles dislodged by
compressed air are potentially harmful. Wear protective
goggles when using compressed air and always direct air
stream away from yourself and others nearby.
D. Remove
1
⁄4"-20 set screw, apply drop of Loctite to
threads and install to depth of .125" to .150" below
gear cover gasket surface.
E. Install S&S Oil Pump Drill Jig, part #53-0013, on gear
cover gasket surface as in Picture 23.
F. Using a .125" (
1
⁄8") drill bit drill angle hole from passage
just plugged until it breaks through pump gasket
surface. See Pictures 23 and 24. While drilling hole,
withdraw drill frequently to clear chips.
G. Remove drill jig and blow compressed air into passage
to remove chips. Note previous cautions regarding
compressed air.
6. Crankcase Modification - 1965-1969 with kits using
#31-6073 body, or 1970-1972 with kits using #31-6003
body - Drill Primary Chain Oil Supply Hole.
NOTE - Objective of this modification is to update early engines
to meter oil to primary chain automatically through breather
gear rather than manually through metering screw device in
pump body. This update requires use of 1973-later style
breather gear such as S&S #33-4239. This gear is not included
in kits #31-6260 or #31-6270
Picture 22 Picture 24Picture 23
Picture 21Picture 20