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Plug gasket

The early primary plugs on K-model and Sportsters with aluminum primary did not use gaskets. With the introduction of the steel primary in 1958, Harley called out a carryover gasket used for the carryover steel plug. With the introduction of the wet clutch primary, Harley changed the oil-fill and clutch-adjustment plugs and used o-rings. They changed the plugs for the 1977 case redesign, but did not change the o-ring until 1978.


Sportster_Engine_Primary_Primary-cover_60567-36_Gasket-plug_1958-1969 Sportster_Engine_Primary_Primary-cover_60567-36_Gasket-plug_1958-1969 Sportster_Engine_Primary_Primary-cover_60567-36_Gasket-plug_1958-1969 CAD
You use this cork gasket under the steel primary plug used on kick-start XLCH models. Problems: While this cork does not leak a drop, oil can weep past the two screw heads used to mount the plug.


Sportster_Engine_Primary_Primary-cover_11106_Gasket-plug_1971-1978 Sportster_Engine_Primary_Primary-cover_11106_Gasket-plug_1971-1978 Sportster_Engine_Primary_Primary-cover_11106_Gasket-plug_1971-1978
This o-ring is used on mid-range bikes, but oddly, runs to 1977, when the plugs themselves changed. Perhaps due to complaints of leaks, Harley changed the o-ring for 1978 models to the below item. Please advise with dimensions. Problems: Perhaps leaking when used with the 1977 primary cover.


Sportster_Engine_Primary_Primary-cover_11139_Gasket-plug_1979-1984 Sportster_Engine_Primary_Primary-cover_11139_Gasket-plug_1979-1984 Sportster_Engine_Primary_Primary-cover_11139_Gasket-plug_1979-1984
This o-ring is used on late-range bikes, but oddly, starts at 1978, a year after the plugs themselves changed.