If you could post the model number, maybe I would have a manual or a close enough. Have you basically split the case at this point or gone further in and found the problem>

You wrote that your number was 917.299080. The owners manual has a clear diagram. I'll look for a service manual in what I have.

Here is a link that might be useful: paper manual IPL

You make some good points. Time wise, there is much more time required if one wants to clean it up as it should be. Figure 3 -5 hours RnR, repair, cleaning, etc. The manual I have shows RnR of the trans only.
You wrote: The diagram on the link you supplied is the same one as Sears Parts, but 100% clearer. This is what I needed. Although my machine is put away in an unheated shed for the winter, Im, confident now that the next time I get to take it apart again, Ill have no problems. Just a little back ground for others who browse this site. At my age (65), Ive been active in maintaining a wide array of my own vehicles and equipment for over 40 years. The mechanical challenge of addressing a problem with this rototiller doesnt really bother me and often Ive faced situations where Id have do things by trial-and-error! But, as has already been brought up getting to this gear case is so labor intensive (someone mentioned 1 and half hours), I didnt want to have do this over and over again. One last point- experience is still a great teacher-technically, a gear case lik! e this should operate in oil bath-like 80w90. Grease, being a solid, will eventually fling off moving parts and simply be in clumps in voids. A recipe for failure i.e. early failure of drive chains. But apparently, the amount of engineering and refinement to include a filler hole, a drain plug and the necessity to make it oil tight, would have probably put this way out of the price range as a consumer grade item.

(PLEASE NOTE: The member responding to your post has chosen not to reveal his or her email address. Therefore, you cannot reply to this message via email.)

Good points, Tom. I worked on one for a friend several yrs and failure was due to lack of lube. Had to junk ot ;cause sears said parts( two brgs and a shaft) were NLA.
The one I worked on had felt seals on the tine shaft so I don't think they would hold 80w90 very well.
Mike