Right Side Crank Seal Replacement

[billtx]

Has anyone done one of these? Can you do this while leaving the engine on the bike or do you need to fully disassemble and split cases.

I have seen a procedure to get the left side (flywheel side) seal out using a drill and sheet metal screw, not sure if it will work on the right side.

Thanks for your help.

 

[jaguar]

I think its possible to replace it without splitting the cases but I've never tried it. By the time the seal needs replacement, the bearings also often need replacement and you have to split the cases to get them out.

 

[billtx]

Thanks. I got it out. It was fairly easy, took about an hour or so following the directions in the Clymer manual (they don't really tell you the seal will come out without splitting the cases). I got the new one in, had to order a collar that goes between the seal and the crankshaft. It had some slight grooves in it that may have contributed to the leak. The guy that owned this before me appeared to change the oil very little, probably caused the seal/collar to wear premature. Oil was black when I took it out.

Crank bearing had no noticeable play in it so I'm not going to mess with it.

 

[jaguar]

So how did you get it out in an hour following manual directions that don't explain how to replace it without splitting the cases? (what you said sounds contradictory)

 

[billtx]

How did I get it out?

Per the manual..

1. Took off right side cover (after taking pipe, brake lever, power valve linkage,etc..off).
2. Took off clutch assy, kickstart assy.
3. Removed primary drive gear using the kickstart gear to wegde between the outer basket gear and the primary gear. Manual gave this hint, or using a brass washer.
4. The seal was very accesible after the primary drive gear was off.
5. A collar (aout 1 inch long) that goes between the crank and seal is easily removed giving access to the seal. The crank itself does not touch the seal. About a 1/4" space between the ID of the seal and OD of the bearing is present without the collar.
what I did that is not in the manual..
1. Tapped on one side of the seal to push it more towards the bearing. there was a little space behind it.
2. Pulled on the seal 180 degrees away from where I tapped on it, and it kinda came out OK after about 5 minutes of going back and forth. To get behind the seal I used a small tool I bought from Cornwell tools in the late 70's. The best way to describe it is a probe bent like pig tail. It went behind the seal at a 90 deg angle and I was able to pull it straight out.
3. Maybe good luck had something to do with it also!

 

[jaguar]

cool
you never said what your bike is. I'm curious to know.

 

[billtx]

99 yz125

also..I should have said between OD of crank shaft and not bearing

 

[placelast]

Some engines are more condusive to the RH seal replacement than others. I seem to remember Eric Gorr mentioning it in his book somewhere, like you can forget Kawasakis, but others are do-able; some both sides. Although it didn't need it, I did it on my son's RMX.