I think i have to replace the crank seal in my brothers yz85. It smokes alot of blue smoke and wont hold an idle. Should I replace the seal and the crank bearing?. And do I have to split the cases to replace the bearing?. Any help? Thanks
Crank seal replacement help?
Started by
kevomxracer
, Apr 16 2012 08:36 AM
9 replies to this topic
Posted 16 April 2012 - 08:47 AM
Are you losing trans, fluid? If you are, then yes, you need to replace the right hand crank seal. Not sure how a YZ85 is, so you would be best to consult the manual. It will tell you everything you need to know. Also, try posting the the Yamaha 2 stroke forum, should be a lot of guys that can help you out over there...
Edited by KcDavis, 16 April 2012 - 08:48 AM.
Posted 16 April 2012 - 10:24 AM
If its only the crankseal you get away with just changing the seal. Try to move the crankshaft up and down (with a screwdrivers help) when you have the engine cover down. A tiny movement up and down means you need to do the roller bearings also and than means splitting engine.
Posted 16 April 2012 - 10:30 AM
Are you sure its just not jetted right. What makes you think its the crank seal. Most oils you would have in your tranny will smoke white not blue anyway.
Posted 16 April 2012 - 10:44 AM
White? White smoke means water IMO. Blue stands for oil. At least in cars.
Posted 16 April 2012 - 01:36 PM
Motor oil generally burns white. two stroke oil burns more blueish. Both are darker than water or coolant, which is just steam, though so I guess you could say that regular motor oil burns a bit blue, but I'd say it's more white. Either way it could not idle and smoke just cause its rich.
Posted 16 April 2012 - 01:52 PM
If it is a crankseal, a good trick to get seals to slide in easily, is to
use Loctite 680, ( green color ) or a similar retaining compound
on the seal and the hole it is going into. Slips right in, and when its dry, makes the seal
stay in, so it wont pop out. Use a very lite coat.
use Loctite 680, ( green color ) or a similar retaining compound
on the seal and the hole it is going into. Slips right in, and when its dry, makes the seal
stay in, so it wont pop out. Use a very lite coat.
Posted 20 April 2012 - 09:26 AM
@te4250 it ran fine until one day and then it would idle and I checked all the adjustments I could.
Posted 20 April 2012 - 09:28 AM
Also I can't check the trams fluid really becaus there's no site gauge. And I checked for wiggle and there was no crankshaft play. And it's deff burning oil because you can smell it and the plug is black and fouled after like 2 hour of riding.
Posted 20 April 2012 - 09:45 AM
You can measure the tranny oil quite easily. Put in a new fill 750ml into the tranny and ride for a few hours then take the oil out again and you see how much went through.
