Cub 108 clutch, tran or worn drive prob??
 

All,

I have a 108 that from time to time when I go to put into gear the gears grind, some times it goes into gear very smooth. My past experiences is when the clutch starts to go bad it slips . So I am not sure if is something worn on the drive shaft or something in the transmission. I would love to hear your past experiences with this and your thoughts.

Thanks

Mike

Welcome to OCC.

When the pedal is pushed down the drive shaft should stop turning, if it doesn't your gears will grind when you put it in or change gears.

It is my experience that you have to watch the parts when you press/release the pedal to see what isn't moving that should and what is moving that should not.

You may get many responses that say "well mine did this" these things may or may not be what your specific problem is.

I would start out by putting the transmission in neutral, lock the pedal down and see if you can turn the drive shaft with your hand (with the engine off the key in your pocket and the spark plug wire off of the plug). If the shaft won't turn then you gotta find out what it's binding on.

If it does turn easy in the above test, then you will have to watch what is going on with the engine running. This test is more difficult, don't run yourself over.

And yes, when the clutch disk wears down, it will slip under a load. A worn out clutch disk will not cause the gears to grind (unless it's binding up on something).

Take the side covers off and look at/watch it.

Yosemite Sam is right. Sounds like the clutch isn't fully disengaging at times. Something may just need lubed or adjusted. Hopefully that is all it needs. The manual is in the technical section.

And:Welcome2:

Everyone is right on.

I will say, that some common problems that cause this condition are; clutch adjustment, bad pilot bushing/bearing, grooves worn in the pins on the 3 pin driver. The clutch will "hang up" on the grooves.

All Thanks for the advise! Unfortunately I won't be able to look at it before Monday evening. I will let you know what I find!

Finally got to look at it. I noticed the throw out wasn't moving out when I engaged the clutch and neither was the friction plate. I put some oil on them and have them and they are moving much better. Once I put it in gear it will allow me to switch gears with no problem as long as the clutch is pressed in. Now if I let off of the clutch at idle and not in gear the gears will grind when I put it back into gear but it is fine after it is in gear. I do notice with the teasing spring which appears to be the small spring behind the throw out is missing except for one wrap where it appears on the parts list it should be 4-5 wraps around the drive shaft Do you think this could be the prob. To me this spring seems like it should push the throw out toward the clutch putting mor pressure on the clutch. Any thoughts would be appreciated!

It will if there isn't any grooves-wear spots where the throw out rides. Odds are the driveshaft needs replaced.
There are instructions in the tech section on rebuilding a clutch. Page one of the clutch rebuild has a picture of the driveshaft that has the wear in the throw out bearing rides.

Just to help you out, here's the link the the write-up:
VERY well done write-up BTW, Dale! :beerchug:

http://www.onlycubcadets.net/forum/s...ad.php?t=33653

Thanks!!!!

:Cub2::Cub2:

Please know that I am not "busting on you" just wanting to clear a couple of things up so we can all be sure you are on the right track.

You say "behind the throw out bearing" the teaser spring should be in front of the bearing. It is meant to "ease" the rear plate into the disk, for smoother take offs. Yes, the teaser spring should be about 4 or 5 wraps around the shaft. It normally won't cause poor clutching just a more jerky take off. If much of it is missing the clutch will slip easier because there won't be as much pressure from the main spring.

One of the sad truths about these older machines is that we never know what a PO has done to it... I've seen more than one Clutch/Drive Shaft put together wrong.

That's actually a physics/math debate. I'm inclined to say this is false. Not trying to spark a debate, because the affect is no minimal it doesn't really matter in this particular application. But in tractor pulling, where even a 1/2 pound of force matters, it would be. This would make a really good debate. If I can find the formula, it wouldn't be a long one, but my calculus is rusty, and I've not been in school for a long time.....