Bobcat skidsteer grabs to right side when backing up

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jjenks01

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Sep 24, 2020
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I just replace the bearings and races on my 753 bobcat axles. The right rear was in bad shape. Now when I am using it and pull back on the right control it seems to grab and really react. Spin around. Generally this is at high throttle. I have retightened the chain bolts nothing was loose and check the hub bolts regular and retighten. I dont remember it being so reactive before I took it apart. I am not sure if this is something to worry about. Thanks. Jack
 

Tazza

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I'd jack it up so all 4 wheels are off the ground, check for any end play and that they all rotate about the same amount when you turn the wheels by hand. Just to check the bearings have no end play.
 
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jjenks01

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Sep 24, 2020
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I'd jack it up so all 4 wheels are off the ground, check for any end play and that they all rotate about the same amount when you turn the wheels by hand. Just to check the bearings have no end play.
Thanks for the reply. I thought if someone replied it would show up on my email. Anyway I will try that. I did take the covers off and the bolts holding the chain gears are tight. So I will jack it up and turn the wheels plus try and pull the wheels in and out to check for end play. If I notice any difference in turning or end play what does that mean? Thanks.
 

Tazza

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Thanks for the reply. I thought if someone replied it would show up on my email. Anyway I will try that. I did take the covers off and the bolts holding the chain gears are tight. So I will jack it up and turn the wheels plus try and pull the wheels in and out to check for end play. If I notice any difference in turning or end play what does that mean? Thanks.
End play means the bearings are worn.
If the rotation is quite different between front and back, it could be chain or sprocket wear.
 
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jjenks01

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Sep 24, 2020
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End play means the bearings are worn.
If the rotation is quite different between front and back, it could be chain or sprocket wear.
I just replaced the inner and outer bearings and races so the bearings should not be worn. I jacked it up and turned the wheels. I can only turn them about 1/4 turn each way not completely around. Same for both sides. It seems like this problem started after I changed the bearings and races. I had a mechanic drive it and he did not really notice it grabbing. He thought maybe the bearings need to be broken in. My son in law noticed that it is hard to drive straight backwards. The right side keeps grabbing. He thought maybe something was in a bind. Could a bearing be in a bind maybe a race came loose?
 

foton

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I just replaced the inner and outer bearings and races so the bearings should not be worn. I jacked it up and turned the wheels. I can only turn them about 1/4 turn each way not completely around. Same for both sides. It seems like this problem started after I changed the bearings and races. I had a mechanic drive it and he did not really notice it grabbing. He thought maybe the bearings need to be broken in. My son in law noticed that it is hard to drive straight backwards. The right side keeps grabbing. He thought maybe something was in a bind. Could a bearing be in a bind maybe a race came loose?
the bearing load should keep the race in place and centered in the housing, I am wondering if the one of the races is not centered in the hub housing , sitting cocked off the housing lip (this would be inner bearing) . Or you have the bearings set to tight. this is just a guess.
 

flyerdan

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I just replaced the inner and outer bearings and races so the bearings should not be worn. I jacked it up and turned the wheels. I can only turn them about 1/4 turn each way not completely around. Same for both sides. It seems like this problem started after I changed the bearings and races. I had a mechanic drive it and he did not really notice it grabbing. He thought maybe the bearings need to be broken in. My son in law noticed that it is hard to drive straight backwards. The right side keeps grabbing. He thought maybe something was in a bind. Could a bearing be in a bind maybe a race came loose?
The quarter turn is troubling; if the chains aren't on the wheels should spin freely in either direction.
If the chains are on there shouldn't be more than about 4" of movement from a fixed point on the tread.
If you have that much slack in the chains, it could be piling up until the motor catches up with the reverse direction and unpiles it. Not a good situation, as it will eventually bind up and break something.
If chain slack isn't an issue, some models have critical clearance for chains, and a master link can stick out far enough to catch, but that should be just an annoying tick.
 
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jjenks01

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Sep 24, 2020
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The quarter turn is troubling; if the chains aren't on the wheels should spin freely in either direction.
If the chains are on there shouldn't be more than about 4" of movement from a fixed point on the tread.
If you have that much slack in the chains, it could be piling up until the motor catches up with the reverse direction and unpiles it. Not a good situation, as it will eventually bind up and break something.
If chain slack isn't an issue, some models have critical clearance for chains, and a master link can stick out far enough to catch, but that should be just an annoying tick.
It was more of a 4" movement. I will be taking it into the Bobcat dealer sometime this winter. Because I just replaced the bearings and races makes me think it has some thing to do with that. Thanks for your post.
 

Tazza

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It was more of a 4" movement. I will be taking it into the Bobcat dealer sometime this winter. Because I just replaced the bearings and races makes me think it has some thing to do with that. Thanks for your post.
I'd suspect the issue is more of a chain/sprocket grab, not a bearing grab. As the sprockets wear, the points will get pointier and can touch the roller perts of the chain and that could be the binding you feel. The 4" travel on eacy wheel seems normal to me, and i'd suspect the issue is not chain/sprocket wear but it's kinda the the only thing i can think of. Even a damaged roller on the chain.
I did have a machine that the roller had opened up somehow. I heated it with a torch and closed it up without issues. Hopefully your issue is the same, or as simple to repair. The hardest part is getting the chains out.
 
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