dewayne Posted March 18, 2007 Share Posted March 18, 2007 Morning to all. My question is my limited slip on my 917H doesn't seem to be working properly. Does this unit have clutches like a car or something else. Any help would be appreciated. dewayne Link to comment Share on other sites More sharing options...
RayS Posted March 18, 2007 Share Posted March 18, 2007 Link to comment Share on other sites More sharing options...
HubbardRA Posted March 19, 2007 Share Posted March 19, 2007 Dewayne, There is a modification that can be made to increase the friction in the diff. I made the modification to one that I was using for tractor pulling. You can see the springs in the parts breakdown above that was posted by RayS. I put a washer underneath each spring where it contacts the housing. This increases the force from the spring when everything is tightened up during final assembly. That one is stiff enough that I can tighten the rear lug bolts with one rear wheel off the ground. It will still slip in an extreme situation, but takes a lot more force to make it slip than with the factory setup. You will need 8 washers, with the ID drilled out to fit over the sleeve, and part of the outside edge ground away to fit flat in the housing. If for some reason (I don't know why one would want to.) you want to lock both wheels together so that there is never any relative movement between them, then that it easy too. If that is what you want, then PM me and I will tell you how. This is not something that should be done for regular use. Link to comment Share on other sites More sharing options...
MikeES Posted March 20, 2007 Share Posted March 20, 2007 Just be careful on reassembly or you will have a locked up rear axle. Of my numerous tractor purchases (some free),a full 1/3 came to me with the diffs assembled wrong. One parts tractor (3415H) I bought in poor condition became a real surprise (bought for the electric lift). We blew a diff in our pulling tractor, so I pulled the diff from this 3415H and to my surprise it was assembled wrong and thus never moved, I had a brand new diff, the grease was still amber clear (though it had set up like taffy). I did not use this diff for pulling I put it in my HB212 and used the 212 diff in the pulling tractor. BTW I learned for tractor pulling to take the springs out and use the older style spacers. Link to comment Share on other sites More sharing options...
HubbardRA Posted March 21, 2007 Share Posted March 21, 2007 Mike, What was your reasoning behind removing the limited slip feature from the diff? The only thing that I can see that would do is keep the tractor in a straighter line, because with a locked unit a tractor will turn to one side if one wheel has more traction. I ran limited slip and locked rears for twenty years, and to me, that is the only way to go, unless you have steering brakes. Link to comment Share on other sites More sharing options...
MikeES Posted March 22, 2007 Share Posted March 22, 2007 Rod, I hatched a diff when I believe I compressed the springs and lost surface meshing area with the spider gears. With the springs out and spacers in the spider gears cannot move laterally. I have never had traction problems with either of our tractors. They always spin out with both tires turning, and we are not all over the track nor do we have one wheel burnouts like the cub cadets. At times we still may need to do a fair amount of leaning to keep the tactors on the track, so we are getting some pretty good limited slip traction without the springs. And for those that are wondering, we do not have the adjustable (slip control) hubs on our pulling tractors. For pulling I use only the newer welded steel hubs. Link to comment Share on other sites More sharing options...
HubbardRA Posted March 22, 2007 Share Posted March 22, 2007 Mike, The only parts we ever broke were one of the removable left hubs on the original setup and then we sheared the key that holds the left side gear to the axle. Never had any problems with a rear after we installed the new style unit that I shimmed. On my motorcycle engine tractor I always ran a fully locked rear. I had such good results that I never even considered using an open diff in it. It was not a Simplicity. I built it totally from scratch and had a solid axle in it from one hub to the other. There was no diff at all. Link to comment Share on other sites More sharing options...
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