Hello guys I'm new to Atv's and the site. I am a shade tree mechanic and it just takes me twice as long to wrench than it does a pro. I just picked up a Moto4 350. Not sure of the year.It runs well. But needs work. My question is why is the drive shaft covered in oil. It looks like it has been like that for a long long time. I rode it for a little bit last night and parked it in the garage. In the morning there was a quarter size oil spot on the floor.What do i need to do to fix this? thanks Mike

 

Engine oil or gear oil? The oil seal out of the angle drive from the engine does sometimes leak on these machines and it is an absolute swine to replace, as it is fitted on the inside of the case. So swinging arm assembly, then angle drive box, has to come off, followed by striping the box and changing the seal. If it is gear oil, it will be coming out of the diff, probably the pinion seal. So rear axle and diff assembly off to replace that. Much easier to keep topping the oil up, like the previous owner did.

 

thanks for the reply.that was the route was going to take.I just wanted to make sure it wasnt something serious.

 

Just changed mine. It is a pain to change... make sure to keep your shims from the middle driven gear. Chances are they may be rusted and rotten like mine.

 

I have heard that by tightening the yoke nut may solve the problem. Any thoughts on this approach?

 

Possible I suppose, but you have to remove the rear end to do this, so it is a lot of work for nothing if it doesn't cure it. You may be able to see if the oil comes from the seal, or the centre of the yoke, when you get the swinging arm assembly off.

 

Im going to put axle bearings in. Does the swing arm have to come off as well? If so i
I'm already there. Is there a bearing in the swing arm for the axle? Looks like there supposed to be one where the brake rotod is. Thanks for your help.

 

Yes,there are bearings in the swinging arm. No the arm doesn't have to come off to replace the rear wheel bearings.