S&S Cycle Oil Carry-Over - Manual (Page 2)

Subject: Oil carry-over associated with S&S ® crankcases
S&S has received reports of excessive oil carry-over associated
with a limited number of S&S Super Stock
® Alternator Crankcases
for big twins. This condition is recognized as excessive oil exiting
the crankcase breather vent after sustained high-RPM operation.
A small amount of oil-air mist exiting the breather vent is normal,
and should no be considered a problem. If there is doubt
concerning whether a problem exists, contact S&S.
Crankcases affected:
Affected crankcases were manufactured between December
1995 and June 1997, with serial numbers ranging from W1848 to
X6239. Not all Super Stock
® crankcases within this group are
affected, and this occurrence has not been associated with S&S
Generator-style or Special Application crankcases.
Before proceeding, it is important to understand that there are
many possible causes of excessive oil carry-over. These typically
include but are not limited to worn or damaged piston rings or
other engine components, restrictions in the oil return line, an
incorrectly machined gearcase cover, and the use of a gearcover
gasket from an incorrect year group.
What to look for:
If excessive carry-over is encountered in association with an S&S
crankcase from the above group and no other cause can be
identified, confirm that the crankcase serial number is between
W1848 and X6239. Suspect crankcases fall within this range, but
may also be identified by the absence of an S&S logo near the
serial number. S&S logo on unaffected cases is illustrated in
Picture #1.
What to do:
1. Remove the gear cover; refer to a S&S Service Manual as
necessary.
NOTE- Before removing the gear cover it is necessary to remove
valve spring tension from the cam by collapsing the pushrod
adjusters. If unfamiliar with this procedure, consult a professional
mechanic.
2. Inspect the oil return holes indicated in Pictures #2, #3
and #4.
3. Compare the oil return hole in the suspect crankcase to the
return holes in Pictures #2, #3 and #4.
If the oil return hole is the same as in Picture #2, the crankcase
may be modified to minimize carry-over; contact S&S Technical
Services at 608-627-8324 for additional information. The
modification may be performed without removing the engine
from the frame.
NOTE - Crankcases of the type shown in Picture #3 and Picture #4
do not require modification.
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Picture 1 Picture 2
Picture 4 Picture 3