Post by bradblazer on Mar 10, 2010 21:25:06 GMT -5
I always had a small gear oil leak at the right side pivot of the front axle on my Kama 554. After roading the tractor on Saturday (in 2wd on the road) I noticed quite a bit of leakage both at the pivot and at the hub.
In my experience, a leaking seal often means a bearing problem, so I wiggled on the assembly with the wheel on and off but I couldn't detect any free play.
I started taking the front hub apart. The big gear and lower bevel gear were in good shape but the vertical shaft showed some ugly wear where it fits through a close tolerance hole inside the pivot bearings. There were also some metallic shavings in the bottom of the case.
When I got the upper gear housing apart, the gears did not look good. The outer ends of the gears were severly deteriorated and there were lots of jagged metal chunks that had been shed by the gears. That was probably the cause of the cosmetic damage on that vertical shaft.
The tractor had not shown any symptoms of the gear problem. I thought I'd better check the left side gears too so I opened up the top gears and found the same type of damage.
Today I called Chip at ARTRAC and he is shipping me new gears.
I removed the pivot seal that had been leaking and it looked like it was poorly installed. One edge was peeled back and it was deformed. It had driven out easily from the far side (without further deformation) so I don't know why anyone would have had trouble installing it.
The hub seal is sandwiched behind the big gear. Chip talked about a clip retaining the stub axle. I saw a split ring back there and tried to pry it apart and it broke. I got it off but figured out it was retaining the axle in the outboard bearing and not holding the gear on. The gear and outer bearing race were just tight on the shaft. I pondered and scrounged around a while and finally supported the very heavy gear across a couple of pieces of 1/2" flat bar and drove the shaft out with a drilling hammer. I think I was driving more against the momentum of the gear than the bar supports. The inboard bearing race and gear spline were both pretty tight fits.
It turns out the "split ring" was actually a hard washer that had cracked in one place long ago. I just broke it in another spot when I tried to remove it with the gear still in place. There was a separate 2-piece clip behind the gear adjacent to that washer.
I still need to get the stub axle out of the outboard bearing and it feels like another tight fit. I have a pack of seals that came with the tractor and it includes the sizes I need. I'll check all of the bearings carefully for damage. I priced them at the local supply and the prices ranged from $35 for the regular ball bearings to about $100 for the biggest angular contact bearing (that outboard stub axle bearing). I hope they're okay.
Brad
In my experience, a leaking seal often means a bearing problem, so I wiggled on the assembly with the wheel on and off but I couldn't detect any free play.
I started taking the front hub apart. The big gear and lower bevel gear were in good shape but the vertical shaft showed some ugly wear where it fits through a close tolerance hole inside the pivot bearings. There were also some metallic shavings in the bottom of the case.
When I got the upper gear housing apart, the gears did not look good. The outer ends of the gears were severly deteriorated and there were lots of jagged metal chunks that had been shed by the gears. That was probably the cause of the cosmetic damage on that vertical shaft.
The tractor had not shown any symptoms of the gear problem. I thought I'd better check the left side gears too so I opened up the top gears and found the same type of damage.
Today I called Chip at ARTRAC and he is shipping me new gears.
I removed the pivot seal that had been leaking and it looked like it was poorly installed. One edge was peeled back and it was deformed. It had driven out easily from the far side (without further deformation) so I don't know why anyone would have had trouble installing it.
The hub seal is sandwiched behind the big gear. Chip talked about a clip retaining the stub axle. I saw a split ring back there and tried to pry it apart and it broke. I got it off but figured out it was retaining the axle in the outboard bearing and not holding the gear on. The gear and outer bearing race were just tight on the shaft. I pondered and scrounged around a while and finally supported the very heavy gear across a couple of pieces of 1/2" flat bar and drove the shaft out with a drilling hammer. I think I was driving more against the momentum of the gear than the bar supports. The inboard bearing race and gear spline were both pretty tight fits.
It turns out the "split ring" was actually a hard washer that had cracked in one place long ago. I just broke it in another spot when I tried to remove it with the gear still in place. There was a separate 2-piece clip behind the gear adjacent to that washer.
I still need to get the stub axle out of the outboard bearing and it feels like another tight fit. I have a pack of seals that came with the tractor and it includes the sizes I need. I'll check all of the bearings carefully for damage. I priced them at the local supply and the prices ranged from $35 for the regular ball bearings to about $100 for the biggest angular contact bearing (that outboard stub axle bearing). I hope they're okay.
Brad
