Clutch Repair Kama 554

[greg_g]

Greg, if your TOB moved off the seat, then the press fit was not adequate. When you re-installed the new TOB, did you tighten the fit between the seat and bearing ID? Or was it a better fit?

This was on the TS354C, the one that had the clutch linkage unknowingly jammed forward by some brush. Since the seat on that sliding sleeve was so badly scored, I simply replaced it.

So the twin return springs mentioned were on the TS354C. I never actually looked for any differences in the KM454 book. Since so many of the parts diagrams on my two tractors are identical, I just assumed the KM454 had two springs as well. My mistake.

The KM454 still has the original clutch and bearings (one of which gets greased regularly). I detected finger wear early on, but adjusted it out before incurring irreversible damage. I now have one spare clutchpack and bearing set for each tractor. That's how I was able to test drive the 3-finger stack height adjustment, and conclude that it can realistically be performed on the bench

I initially got one of those bearings from Chip that didn't have a hole. Since it's not a sealed bearing, I didn't trust it to last without periodically refreshing the grease. It would have been easy to drill a 2mm hole myself, but I didn't want to chance metal fragments circulating in the grease. So I sent it back to Chip - with a request that it be replaced with one that DID have a grease hole. Now I can grease the TOBs on both tractors - at will, and without splitting.

//greg//

 

[3RRL]

There's no need to split the tractor, if all you want to do is remove the front driveshaft. The method I described will do that. I know, because I had to remove the one on my KM454 once to do some work on the transfer case.
//greg//

After careful consideration, I came to the conclusion that the 4wdriveshaft installation or removal on 454 is different than on mine and Brad's 554. Both of us found that once the rear collar is un-pinned there is just not enough room to get it out with the tractor together. When you slide the shaft rearward, it hits the rear shaft by a lot. The front spline is still engaged by a lot at that contact point, so no go for us. Perhaps another 554 owner can comment on this if we are both screwing up?

 

[greg_g]

... if we are both screwing up?

Not necessarily screwing up, since you both have one more cylinder than do I (KM454 has the 395 engine). Longer engine block necessarily means comparatively more distance between the transfer case output spline and front diff input spline. Stands to reason the driveshaft is proportionately longer too. Maybe too long

Your pair may have been manufactured in a transition period - a work in progress if you will - one that hadn't yet caught up to the parts diagram (or vice versa). Remember the "spacer" that neither of us found? If your driveshaft was shorter - AND a spacer was inserted before coupling it with the transfer case spline - that would give you the ability to do what you want. So there's a chance that you and Brad actually DO have a driveshaft that's a tad too long for it's own good. If there's anything to this premise, then cutting and rebalancing the shaft might be a feasible solution after all.

But mine definitely comes off without splitting, I've done it. But I didn't slide mine rearward initially. After the collar was pushed forward exposing the gap between splined sections, I shoved the driveshaft off to one side until it cleared the transfer case input shaft - and THEN I pulled it rearward.

//greg//

 

[3RRL]

But mine definitely comes off without splitting, I've done it. But I didn't slide mine rearward initially. After the collar was pushed forward exposing the gap between splined sections, I shoved the driveshaft off to one side until it cleared the transfer case input shaft - and THEN I pulled it rearward.
Exactly...
When I tried to pull mine off to the side, the engagement on the front spline was too great to allow it to move enough to the side or bottom like yours. It remained almost lined up with the rear shaft except maybe a 1/2" drop off center is all.
That's why I said I didn't want to break or bend it trying to clear the rear spline.
Perhaps with a larger gap (and a spacer) it would slide back enough to allow a little more tilting to the side or down to clear that rear spline. Personally, I'd want a longer connecting bushing to keep the same amount of splined engagement. I'd have to broach or wire EDM the gear profile into a new, longer bushing. So there is room for improvement, but I'm not gonna do that.

 

[3RRL]

Today I cleaned the rust off every part.
Also roughed up both clutch discs and flat stoned all the pressure plates with a 220 grit YLS stone.
It was a lot of tedious work but worth it to me. One of the photos shows how dirty and rusty the bolts were for comparison. All the plates were that way before I wire brushed them.

 

[3RRL]

It looks like some of these Chinese tractors may be suffering from the same clutch related problem?
I wonder how many others have noticed excessive finger wear or TOB seize up? Clutch wear itself, at least on mine was minimal. Had the TOB not frozen, the fingers wouldn't have worn down either. I might've had a good working clutch for 5,000 hours or so, who knows?

With that in mind, I'm still wondering about being able to lube the TOB itself and also the sliding TOB Seat.
Some say no lube and some say yes, lube it. I know you don't want any lube to get into the clutch, so I'm torn between the two. Inspecting my sliding TOB seat, I saw there is a cavity ring between the two machined ID's. When I took it off, it had some residual grease in there. Looks like the cavity is there on purpose, perhaps to house grease? I know it's more work to machine that undercut in there, so I'm thinking it's got to be on purpose.



I mentioned before I'd like to add a grease fitting right to that sliding seat.
One I can get to from the same hole in the housing. If I'm going to do that, obviously now is the time.

I'm curious, what do others do there?
I'd like to hear the pros and cons. I already got Chip's opinion and I value that, but I'd like to hear yours.
Not just Chinese tractors, but all brands? Are your TOB Seat and TOB itself lubed?

 

[Diamondpilot]

How about some dry lube like a Graphite used on locks????

Chris

 

[Brad_Blazer]

I like the graphite idea. Bore a little hole to periodically fill the cavity with graphite powder or machine a (3 piece?) split ring of solid graphite to fit the cavity.

 

[SPYDERLK]

It looks like some of these Chinese tractors may be suffering from the same clutch related problem?
I wonder how many others have noticed excessive finger wear or TOB seize up? Clutch wear itself, at least on mine was minimal. Had the TOB not frozen, the fingers wouldn't have worn down either. I might've had a good working clutch for 5,000 hours or so, who knows?

With that in mind, I'm still wondering about being able to lube the TOB itself and also the sliding TOB Seat.
Some say no lube and some say yes, lube it. I know you don't want any lube to get into the clutch, so I'm torn between the two. Inspecting my sliding TOB seat, I saw there is a cavity ring between the two machined ID's. When I took it off, it had some residual grease in there. Looks like the cavity is there on purpose, perhaps to house grease? I know it's more work to machine that undercut in there, so I'm thinking it's got to be on purpose.

I mentioned before I'd like to add a grease fitting right to that sliding seat.
One I can get to from the same hole in the housing. If I'm going to do that, obviously now is the time.

I'm curious, what do others do there?
I'd like to hear the pros and cons. I already got Chip's opinion and I value that, but I'd like to hear yours.
Not just Chinese tractors, but all brands? Are your TOB Seat and TOB itself lubed?

I would favor a grease fitting on the sliding seat. With judicious geasing it should be a pure benefit. Short of that, I would not put it back w/o some lube. If it is to be non renewable it should be dry. I would use Slip Plate aerosol graphite by Superior Graphite. It forms an extremely thin coating that stays in the joint. I believe many parts in your assembly would benefit from it. Grainger has it. NH tractor dealers stock an acceptable CNH substitute. I recommend against other pretenders.
Concerning your driveshaft-I gather there is no front spline joining collar analogous to the rear one?
larry

 

[3RRL]

Regarding the sliding seat, in the plastic injection mold making trade there were medical molds (and others) that couldn't have any contamination from lubrication. We used to buy Graphalloy Graphite Impregnated stock and turn up our own bushings if they did not supply sizes for our custom applications.
We also used Graphite Plugged Bronze Bushings such as these for similar reasons.
The bronze was used for mostly low pressure though. I suppose I could turn the ID of the Seat and press one in, but I'd rather install a no brainer Zerk fitting.

That's why I asked the lube/no lube question.
The intent is to prolong the life of the part (parts for some) that failed and perhaps avoid (another) tractor split. As you can see from my documentation, the clutch itself and other components could last for thousands of hours had the throw out bearing not frozen causing damage and consequently, a failure.

LOL ... I'm just trying to make them work better without making it worse. Maybe I'm over thinking this, but having seen it with my own eyes causes me concern. What I'm getting at is I don't want to be splitting the tractor every 500 or 1000 hours to change the throw out bearing, especially if the other components are still good.
I can understand having to change the clutch when it wears out, of course.

Another factor to consider is that when I spoke to Chip, he told me they don't get many Kama's in for service with 500 or 1000 hours because no one has logged that many hours on them yet. He said they've gotten some with 200 and 300 hours. (Correct me if I'm wrong please Chip). With that in mind, perhaps there might be (common) failures looming ahead for others when approaching those hours ... problems that we're not aware of yet because lack of a track record (history) with these machines at the higher hours like mine? You can see from Greg's post and photos, his problem was of similar nature.
Anyway, something to think about, right?