You've got me know! I had a quick glimpse at the diagram and then posted.
From memory, the only O-ring is the 20mm (ish) one that sits around the base of the oil pump housing. Then there is the seal on the pump shaft, and the thrust washer between the engine casing and the pump shaft.
I can't remember seeing the small O-ring, even on the latest casings/pump.
Can you post any pictures?
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Andy.
NSR-WORLD.COM
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