This is the part that sticks in the top of the crankcase and/or flywheel cover that the breather pipe fits to
Fits straight in with no modification
Original part # 498-15371-00 superceded by 583-15371-00
These
parts were then superceded by 3YJ-15371-00 but this part has proved too
big to fit in the crankcase hole, it needs trimming with a knife to
fit. So we had these high quality replicas made of the originals in
plastic.
To fit tap into the crankcase with a very small hammer and protect the top with some kitchen roll to save marking them