Need your help changing drive chains on a Bobcat 642

[ibbuckshot]

Greetings folks,
I have opened up the chain case on my 642. The machine is up on blocks and jack stands..Once things were open I attempted to rotate the sprockets/chains to locate a master link or if none found I have a chain breaker ....problem is I cant get the wheels/chains to rotate at all...I moved the steering linkage forward and rearward but I still can not get it to rotate.... I went to the manual and all it says is to look for the master or break the chain....there is nothing that I can find on how to rotate the wheels/chains/sprockets ......Thanks in advance for your advice....

 

[flyerdan]

I think that the drive motor has to come out, or at least the sprockets need to come off of it as it won't turn without fluid driving it. I'm looking at the diagram for a 632; if it's similar, it has a double drive sprocket on the motor with a tapered keyed motor shaft. If there isn't slack enough to get the drive sprocket all the way off, it should allow the wheels to turn enough to get to the links, which are called out in the diagram.

 

[ibbuckshot]

thank you sir, I was hoping there was some way of rotating the system that I did not know about.....

 

[ibbuckshot]

Greeting folks,
I have been able to remove the chains by unhooking the hyd lines.....and have found the two brake disks need to be replaced. What do these disks normally sell for ? Can anyone point me in the direction to find replacement disks on line...I think the bobcat part # is 6559206....The disks I need are the steel ones...not the ones made out of solid gold....Any help in finding these would be appreciated.
Hours later....I am in another fix...In attempting to remove the right rear chain it is not jamed at the rear of the sprocket.....I have never done this before and it shows...I tried to remove the chain from the bottom and when the end of the chain reached the 3 o clock position, the end of the chain fell off the sprocket and lay doubled up under the sprocket and against the back wall of the chain case.... As far as I can see I may have to try to reach the rear sprocket nut, remove the sprocket, in order to get the chain uncaught......In anyone has a fix so that I dont have to try to remove the sprocket to get the chain loose Please let me know.....If anyone is thinking of replacing drive chain etch this in stone, Never try to remove the chain by rotating it from the bottom of the sprocket....Always rotate and remove the chain from the top....
Have fun,
buckshot

 

[laurencen]

when I changed the chains on the 742 we lifted the machine off ground, broke the chain and using a split link joined it to the new one, then with fuel shut off cranked the motor wile using the drive levers to feed it over the sprockets