KAMA 554 Front Drive Repair

[tommu56]

Rob

What about welding a washer on top that fit that top of taper and and one on bottom that fits there. Clean it up good fill between with devcon insert greased tie rod and snug it up tighten after it hardens.

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tom

 

[psj12]

What about brazing the hole and then rereaming the taper. I'm fairly certain it would be a standard taper. I'm not sure where a reamer of the proper taper could be obtained.

 

[3RRL]

Parry and Tom,
I'll wait till I get those pieces to my shop to any work on those crummy holes, although the suggestion of the Devcon is a good one for the time being. At home I have all kinds of tapered reamers and endmills, but none of that machining is going to happen here at camp.


What I was thinking about is making the sleeve with a shoulder on the bottom side and then counter boring the hole in the casting on the bottom. Make the diameter of the hole (and sleeve) so it is smaller than the bottom of the tie rod. Add a large enough diameter washer on the bottom side above the nut to retain the sleeve inside the casting. The sleeve should be "captured" in the casting that way.

Those are all good ways to do a really proper fix, but in reality I will probably file the casting flat and stick the ball rod back into that screwed up hole in the casting. All that stuff is at camp now and there's no way I'm driving up there to get it before Larry and the replacement parts get here. It's just too hard and no time to do correctly at camp for now.

When I move up there and set up my shop, I will do it at that time. I'll document making and installing the sleeves in a new thread.

 

[Bob Rooks]

This stuff is hard to beat: Chockfast

 

[dfkrug]

This is not pointed (directly) at Kama, but I will intertwine a personal story. I purchased a Kazuma 150CC ATV for my son a few years ago. It ate a reverse gear rather quickly and was replaced under warranty. I replaced it and it snapped an axle off at the hub soon after that. Next was another reverse gear and replaced it myself. The third reverse gear that broke destroyed the entire gear cluster and trans case. I ended up removing the entire trans unit and machining a splined shaft coming of the rear CVT clutch and supported it with a pillow block bearing and attached the countershaft sprocket in that manner. It has worked great since. Before removing the trans entirely I considered having new gears cryogenicly hardened but the company I was going to have do it explained they see a lot of gear sets and other components manufactured in China come from customers like me these days. He said they could indeed harden the material but the bottom line was the quality of the original material was the real problem and while you could help it, you can't make it into something it isn't. Other components of this 4 wheeler have held up very well, but they seem to be "over built". I think China will eventually emerge as a great manufacturing nation similar to Japan, but until they can work though some things like materials deficiency's, buyers of their products may get a product that is very attractively priced but may have to trade that for a little aggravation. I'll guess those gears were "well" hardened but are inherently going to be a weak point. I think Rob has a real work horse with a great price and proper design but will occasionally have this sort of repair until the manufacturers have access to better overall materials for some applications. Another great post Rob!!

Good story, Darryl. One day I may get one of those Chinese ATVs. I am
sure they will continue to improve. They are quite inexpensive.

I agree that China's manufacturing rep will keep on improving, much like
Korean manufacturing has already. It was with some trepidation that I
bought several new Korean tractors a few years ago, and I have not been
disappointed. I may have even been willing to buy a Chinese tractor at
one point, since I have always been willing to do my own repairs. At the
time there were no HSTs, so that kept me from doing so.

A bit more care in assembly would be nice, as well as materials improvement.
I just rebuilt one of those Harbor Freight 5" hyd cyls used in their big
log splitter and the materials seemed OK, but one of the seals was outright
missing and the piston nut was loose!

 

[magyarbacsi]

Bob Rooks
Where can you purchase Chockfast Orange? The sites I looked at sofar all are out of country and dont list the price or in what size it is available. Any dealers close to Seattle?

 

[IH3444]

3RRL, I have enjoyed reading your post, and documentation. Having a bit of a background in material sciences, I agree that the chinese steel may be of questionable quality, and heat treatment. After your job is done, you may want to think about investing in some high quality synthetic gear oil. If the gear parts never really touch due to having a film of extreme prssure oil between them, then they should never wear through the harden surface in the first place. Just a thought.

 

[Bob Rooks]

Bob Rooks
Where can you purchase Chockfast Orange? The sites I looked at sofar all are out of country and dont list the price or in what size it is available. Any dealers close to Seattle?

It is made by Philadelphia Resins, is available in 1 & 5 gallon quantities, and is available at most professional marine hardware stores and ship chandlers.

 

[3RRL]

Well, I finally got my Kama completely repaired during that period where Loretta's tractor arrived. It has been a hectic several weeks to say the least. I have some photos, but unfortunately none technical enough to show the step by step repair taking place.
Then on the other hand, some of you are probably saying Thank God for that! hahaha

Anyway, I got a bunch of gears, bearings, shims, seals and stuff for the repair. But as I said earlier, the only real damage was to the two sets of miter gears. Both the left and right drive axle and reduction gears were replaced. I also replaced a couple bearings that might have had some shavings in them, just to be sure. Then also all the "O" ring seals and a couple retainer clips.

 

[3RRL]

Prior to that, Loretta and I spent an entire day cleaning the other gears and components and getting them all organized for the re-assembly. This turned out to be a major PITA as I soon ran out of room and tables. There were a lot of parts that I needed to "look at" so I'd get the assembly done in the right order.