counter shaft seal ,78

[buddy]

Hi:
Any tips on replacing the counter shaft seal. Sproket was loose but the bike has a few km on it an lots of old oil under case. 'Doing the clutch seal too, done that one before.

 

[sethhazuga]

Hi:
Any tips on replacing the counter shaft seal. Sproket was loose but the bike has a few km on it an lots of old oil under case. 'Doing the clutch seal too, done that one before.

If the bike has lot of miles on it and the seal is leaking I'd replace everything. (seal and sleave)
That being said if the seal doesn't want to budge with a pick or small screw driver, if that doesn't work, take a self tapping sheet metal screw and drill it into the metal part of the seal.
Be careful not to go to far and hit the bearing.

get a chanfer tool to remove and sharp edges.

and use a big socket to drive it in.

 

[DogBunny]

If you are asking about the seal behind the drive sprocket, it comes out very easily. With the sprocket removed, there is nothing holding the collar, part #26 in this drawing:
http://www.biker.net/77-79_650_parts/engine/transmission.PDF
Remove the collar, and you will easily be able to remove the seal, preferably with a seal remover, or with a screwdriver if you must.
Take careful note of how far in the original seal is. It is easy to push the replacement seal too far in. Yes, you should chamfer the edge first.

 

[weekendrider]

If the sprocket is loose even a new seal will leak?

 

[Tim of DO THE TON]

The sprocket doesn't help seal anything. I think the OP needs to clarify what they meant by 'loose' in reference to the sprocket.

 

[weekendrider]

Probably not much more than finger tight. I was under the impression it was a fairly common problem/maintenance check. Loose and they tend to weep. Maybe I'm the only one this happens to.

 

[Tim of DO THE TON]

Really? I've never actually heard of that happening. I always assumed the nut on the sprocket only really needed to be about finger tight - certainly not torqued down - as it only serves to keep the sprocket from moving side to side, and the nut is kept in place by the tabbed washer.

Will pay closer attention when I put the engine I just took apart back together

 

[weekendrider]

I've been using 80 lbs on mine. A 5twins quote from another thread.

Yes, the counter shaft will leak if the sprocket is not installed or installed tight enough. Like many of the other specs on this bike, the torque for the mounting nut was changed several times during production for no apparent reason. Best seal is achieved by using the highest spec given, 72 - 87 ft/lbs.

Best way to cure the pushrod seal leak is new seal, new bushing behind the seal, and the long rod. The short rod moves side to side more and tends to wear out the bushing. If the bushing is badly worn, sometimes a new seal won't even help.

 

[buddy]

thanks for the tips! Great site. /The nut was loose, floppy.Sprokets to be replaced with 17 & 32

 

[SantaFeTrailer]

Take careful note of how far in the original seal is. It is easy to push the replacement seal too far in. Yes, you should chamfer the edge first.

Hey Dogbunny or anyone else: well I didn't pay enough attention when I removed it so now I don't know how deep to set it. With what I felt was reasonable pressure it is not flush with the case. I can't seem to find a good picture of the correct install. Any advice?

 

[gggGary]

Here you go;

 

[SantaFeTrailer]

Thank you Gary, that was exactly what I needed to confirm that I f***d it up. I think I didn't do enough chamfering so it wasn't seating right and then I messed it up banging on it too hard when I went back out to the garage last night. I ordered a new seal and will try again.

 

[5twins]

Those pics also nicely illustrate the splined shaft inside the metal sleeve. That's why the sprocket nut has to be really tight. Oil can and will migrate out between the shaft and sleeve along those spline cuts if the sprocket is loose. The sleeve gets pushed against the inner race of a bearing inside the motor. It has to seal metal against metal there. The sprocket also has to seal against the outer end of the sleeve, and the sprocket nut and lock washer against the outside of the sprocket. All these metal to metal sealing points require a very tight sprocket nut. Even then, you may not get a 100% seal. This is what I see every spring when cleaning under that cover, slight oil streaking from the nut. It's not dripping oil or badly leaking, it's just not quite a 100% seal .....

 

[XSLeo]

I guess you could pull the sleeve and coat both ends with Yamabond, let dry then install.
Leo