Oil pump leak

[Scooter]

Hi guys,

I've just got the bike running after several years of storage and rebuild/restoration.

I have had it running at idle to bleed the oil pump and heat cycle the engine.  I have noticed though that there is a small leak of 2T oil from the underside of the pump, which runs down the side of the cases (see pic).  Has anyone experienced this?  As far as I can tell it's not coming from the hoses, and there's only the one gasket behind the pump, with no other o-rings etc. Is this the most likely source of the problem, or are there other things to look at?

[Arrow]

Hi, the oil is coming from around the end of the plunger shaft. Early failure of the front seal is very common on this generation (with 1kt main casting) of pump.

[Scooter]

Thanks Arrow,

Is that the gasket where the pump mounts to the sidecover casting, or another internal seal within the pump?

[Arrow]

The seal in the top casting. The top casting is the one held on with the four screws.

[Rasher]

Just fitted new one with engine rebuild.

AFAIK pump is sold as a unit and spares not available.

[Arrow]

Just fitted new one with engine rebuild.

AFAIK pump is sold as a unit and spares not available.

A small amount of internal pump spares are available. That particular parts fiche is only available/visible to main dealers.