Oil Pump Issues

Post Reply
Anthony Duffield
Site Admin
Posts: 300
Joined: Sun Aug 11, 2013 8:13 am

Oil Pump Issues

Post by Anthony Duffield »

I suspect I have an issue with the oil pump on my Commander having found that that the gearbox oil level slowly increases. I have checked the pipes and connections as much as I can through the cover finding that all seems to be OK, perhaps its the pump shaft seal. Has anyone else had similar issues with their oil pump?

I have no records from the previous owner indicating that the pump has been renewed so would guess that it is original, the bike has covered 82000 miles.

I have searched the forum but can find no mention of problems with the oil pump.
Ian
moderator
Posts: 113
Joined: Fri Jul 20, 2007 5:45 pm

Re: Oil Pump Issues

Post by Ian »

I seem to recall that Frank Westworth had this problem. It was found to be a seal either between the rear chaincase or the primary case, I can't recall. It allowed oil into the gearbox.

It's a big job to do, and the seal is pennies! I'm pretty sure Mr Negus of this parish has written about this.

Hope this helps,

Ian.
Anthony Duffield
Site Admin
Posts: 300
Joined: Sun Aug 11, 2013 8:13 am

Re: Oil Pump Issues

Post by Anthony Duffield »

Ian,

Many thanks for the reply, I had another good look yesterday with the inspection cover off and engine running, moving the oil control lever to max by hand I could not see any oil leakage around the oil feed pipes, I did this until the engine began to really smoke so feel confident that the issue is not the pipes or connections.

There is an O Ring between the pump and plate it bolts to if the shaft seal is leaking it could get past the O Ring causing the gearbox oil level to rise, I need to measure how much oil is leaking into the gearbox and for how long. The pump is a Yamaha part ANL have one in stock so that will be the next step.

Some years ago I had gearbox oil leaking into the enclosed chain space, that was as a result of a worn lip seal that runs on the sprocket, not an easy job for sure.

Thanks again for your help, I will let you know what I find.

Tony
R Williams
moderator
Posts: 3
Joined: Wed Apr 07, 2021 8:39 pm

Re: Oil Pump Issues

Post by R Williams »

Hello, on my air cooled bike, I fitted a perspex cover on the gearbox instead of the aluminium one which makes for easy checking of the level . I glanced at it one day and the level was over halfway up the perspex and it turned out that the supply pipe to the pump was split !!.
User avatar
Interpol2471
moderator
Posts: 1349
Joined: Mon Oct 20, 2008 1:02 am

Re: Oil Pump Issues

Post by Interpol2471 »

Nice quiet gearbox lol
Various rubbish in various states of decay.....
Post Reply