I have read this means the water pump in faulty.
Please can someone confirm this, and what needs replacing?

Thanks.

The seal on the water pump has braoken down.

Thanks Knacked.

Is that a side panel off job, done from the inside?
And what sort of seal is it?

Take the water pump cover off, take the impellor off (normal nut/bolt direction) and prise out the seal, push a new seal back in and reverse................

You might find a problem with the impellor rusted on and in taking the impellor off you break some of the teeth on the water pump drive shaft. In this case you need a new drive shaft and you will have to take the clutch cover off to replace it.

Thanks, I'll give it a careful go.

So how the hell do you get the impellor undone on the bike?

I have a spare side panel with impellor and oil pump gears, and with the impellor shaft clamped in a vice (protected jaws) I still can't get thing off.

you might find the impeller is on a left hand thread. used to be on the old CR's anyway
Jon

Its possible, but from the shape of the vanes on the impellor I would think it revolves clockwise. So surely it would un-do in the normal direction.

All the impellors I have taken off CRMs have been as a 'normal' bolt/nut so I would doubt you have something special.

As I have said previously they can rust on. If they do this the end of the shaft may shear off rather than come out of the impellor. To avoid this put some antiseize compound on the shaft where the impellor screws on.