2005 EC200 Continual RH Crank Seal Failure

[NHtrailrider]

I have a 2005 EC200 that has eaten two RH crank seals in less than 1 hour of run time. The bike is burning trans oil.

I replaced the inner o-ring on the crank both times. The first replacement I used the all-balls kit and the second I used an OEM seal. The seal spacer did have a small groove in it that I sanded down smooth.

The bike has a fresh replated top end and new piston. It starts easy and idles well. It smokes excessively when on the gas in the mid-top range of the throttle. Both PV and crankcase vent hoses are open and unclogged.

I am now thinking it could be the center case gasket? Would a leaking center case gasket allow trans oil into the combustion chamber? Am I missing something or does anyone have any ideas?

 

[SS109]

If it's destroying right hand crank seals then that would lead me to believe the crank bearing on that side is failing.

 

[Jacob 'Berg]

+1. If it is going through crank seals in an hour do not wait to split the cases and replace the bearings. ie. I would not continue to run the bike, or you will be replacing more than bearings.

Crank may need new conrod and big end bearing if it has not been done, given the bikes age. Cheap insurance while you have the cases apart.

 

[(F5)]

Repack muffler to get rid of continuous smoke. They get so caked up.

 

[Hellcat]

On my 2001 xc200 the oring in it was a thinner one than the 250/300 of that era and newer . If you sanded the crank bushing groove away you need to buy a new bushing . But you can’t cause they are discontinued. Sometimes you can turn it around and have crank seal wide in another area . I have hunted the globe for new crank bushings and find a pile of them from old Gasgas factory but they got damp and are no good . A 200 rieju uses one that is all same size except for the width . It’s too long .