Greeting folks, I have finely broken open the case to replace the drive chains on my 642. The machine is up on blocks and jack stands. I need your advise on how to rotate the chains in order to find the master link, if any. The wheels/ chain sprockets will not rotate...I tried to moving the steering linkage forward and backward hoping I could get things to rotate.....no good....All I can find in the manual is to split the chain or find the master but there is nothing on how to get the assembly to rotate while not under power ? ? ?
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When the drive motors are full of oil, they will not rotate without a lot of force. The oem chains have no master links, so if they have never been changed, there will be no master links. The only way to get it to rotate is for you to remove the motors or at least the hoses to allow it to spin.
Thanks Tazza, After removing the hoses from the drive motors I could find no master links. I used a chain barker and removed a front and rear chain on the right side in order to take them to Bearings and Drives to match up for the new ones.....I have now found the center hubs of both brake disks are bad. I think the part # for the 642 is 6559206. Anyone out thee happen to know what these disks would "normally " sell for? Would you or anyone else happen to know where I can order these two disks on line ? Another question is what is the thickness of the brake pucks. I want to be able to measure them to see if they need to be replaced........... Have fun, buckshotWhen the drive motors are full of oil, they will not rotate without a lot of force. The oem chains have no master links, so if they have never been changed, there will be no master links. The only way to get it to rotate is for you to remove the motors or at least the hoses to allow it to spin.
Greeting folks, Now I'm in another fix....when trying to remove the right rear chain I didn't think about the sprocket rotation....I tried to remove the chain in rotation from the botttom of the sprocket. What happened was when the end of the chain reached the 3 o clock position it fell off the sprocket and is now doubled up at and under the sprocket with little or no way of getting the pile of chain stretched out to have it move under the sprocket ....I am hoping someone has has this happen to them and came up with a fix...If not, it appears I may have to "try" to remove the nut holding the sprocket in order to remove the sprocket and then the chain..... There is no way in hell that I or anyone else should try to take these chains out from the bottom.....etch this in stone.....If anyone has a fix so that I don't have to try to get the sprocket nut off PLEASE offer some kind words of direction..... Have fun, buckshotThanks Tazza, After removing the hoses from the drive motors I could find no master links. I used a chain barker and removed a front and rear chain on the right side in order to take them to Bearings and Drives to match up for the new ones.....I have now found the center hubs of both brake disks are bad. I think the part # for the 642 is 6559206. Anyone out thee happen to know what these disks would "normally " sell for? Would you or anyone else happen to know where I can order these two disks on line ? Another question is what is the thickness of the brake pucks. I want to be able to measure them to see if they need to be replaced........... Have fun, buckshot
Sorry, i have no fix for the chain, hopefully you can jiggle it around enough to get it out or else you need to pull the bolt, the bolt that is SUPER tight and has no room to get leverage on from the inside....Greeting folks, Now I'm in another fix....when trying to remove the right rear chain I didn't think about the sprocket rotation....I tried to remove the chain in rotation from the botttom of the sprocket. What happened was when the end of the chain reached the 3 o clock position it fell off the sprocket and is now doubled up at and under the sprocket with little or no way of getting the pile of chain stretched out to have it move under the sprocket ....I am hoping someone has has this happen to them and came up with a fix...If not, it appears I may have to "try" to remove the nut holding the sprocket in order to remove the sprocket and then the chain..... There is no way in hell that I or anyone else should try to take these chains out from the bottom.....etch this in stone.....If anyone has a fix so that I don't have to try to get the sprocket nut off PLEASE offer some kind words of direction..... Have fun, buckshot
Sadly i don't have details on the pucks, i got a machine once that a previous owner put a coin between them to take up the slack, it acutlly worked quite well. Does bobcat have the brake discs available? I have seen the inner part worn out on a machine before, not sure how it happened, but it did...
It took about four hours of screwing around but I finely got the chain out. Made a pointed tool with a 90 degree point on the end and was able, together with a friend moving the rear wheel back and forth, to get it out...I am soooooo thankful I did not have to try to take the sprocket bolt out....I like the idea about a spacer behind the pucks.....but I dont know what the puck in good condition measures..... the brake disks are available from bobcat but are made of gold.....Is there an on line source for any of these brake parts that you know of ? ? ?Sorry, i have no fix for the chain, hopefully you can jiggle it around enough to get it out or else you need to pull the bolt, the bolt that is SUPER tight and has no room to get leverage on from the inside....
Sadly i don't have details on the pucks, i got a machine once that a previous owner put a coin between them to take up the slack, it acutlly worked quite well. Does bobcat have the brake discs available? I have seen the inner part worn out on a machine before, not sure how it happened, but it did...
Glad you git it out, I don't know how you'd get enough torque on it to get it off.It took about four hours of screwing around but I finely got the chain out. Made a pointed tool with a 90 degree point on the end and was able, together with a friend moving the rear wheel back and forth, to get it out...I am soooooo thankful I did not have to try to take the sprocket bolt out....I like the idea about a spacer behind the pucks.....but I dont know what the puck in good condition measures..... the brake disks are available from bobcat but are made of gold.....Is there an on line source for any of these brake parts that you know of ? ? ?
Sadly no idea on alternate sources. Just how bad is the disc? The brake is for parking, even worn, as long as it still holds......
I'm back,, After removing the chain I took it to Miller Bearings here in Ocala and after they inspected the chaiin I was asked why I am changing it....I informed them that I was experiencing, what I thought was the cain jumping the sprockets....causing a loud bang when loading out of a bank, stock pile or digging with any degree of force applied to the forward motion of the machine....The loud bang was happening mostly when pressure was being applied to left side steering stick... Sometimes to the right side also but mostly on the left side...After opening up the machine there seemed to be, what I thought was, a good deal of chain droop. The thought was that there may be excess chain length....they stated, based on the chain condition, that they would advise me not to change the chain..We decided to shorten the chain by removing two full links and inserting a master link along with a 1/2 link...therefor shortening the overall length of the chain by 1/2 link....One major question for all you folks now is " What size chain is OEM size for a 642 skidsteer?" I was informed some months ago that the chain should be size 80.... This Diamond chain that I removed from my machine is size 60...There is a 60SH stamped into the side plates of the links....I need to know if the proper size is 80 or 60....Your experience on this fix would be greatly appreciated.... Have fun, buckshotGlad you git it out, I don't know how you'd get enough torque on it to get it off.
Sadly no idea on alternate sources. Just how bad is the disc? The brake is for parking, even worn, as long as it still holds......
I would be skeptical putting a half link in as they are normally the weak point. If you took 60 out that would be the size as 60 wouldn't fit 80 sprockets. It could be someone put too long of chains in assuming your bearings aren't loose causing slop in the chainsI'm back,, After removing the chain I took it to Miller Bearings here in Ocala and after they inspected the chaiin I was asked why I am changing it....I informed them that I was experiencing, what I thought was the cain jumping the sprockets....causing a loud bang when loading out of a bank, stock pile or digging with any degree of force applied to the forward motion of the machine....The loud bang was happening mostly when pressure was being applied to left side steering stick... Sometimes to the right side also but mostly on the left side...After opening up the machine there seemed to be, what I thought was, a good deal of chain droop. The thought was that there may be excess chain length....they stated, based on the chain condition, that they would advise me not to change the chain..We decided to shorten the chain by removing two full links and inserting a master link along with a 1/2 link...therefor shortening the overall length of the chain by 1/2 link....One major question for all you folks now is " What size chain is OEM size for a 642 skidsteer?" I was informed some months ago that the chain should be size 80.... This Diamond chain that I removed from my machine is size 60...There is a 60SH stamped into the side plates of the links....I need to know if the proper size is 80 or 60....Your experience on this fix would be greatly appreciated.... Have fun, buckshot
It could also mean that some where in the past someone replaced the chain with the wrong size. So far I have asked in a number of posts about the OEM chain size and no one has offered the information....I am not willing to spend hundreds on replacement drive chain and have it maybe be the wrong size...I would be skeptical putting a half link in as they are normally the weak point. If you took 60 out that would be the size as 60 wouldn't fit 80 sprockets. It could be someone put too long of chains in assuming your bearings aren't loose causing slop in the chains
I don't blame you for wanting to do the job right the first time and not waste money. The only way it could be wrong would be for someone to change the sprockets as 60 won't fit a 80 sprocket. If your chain supplier said your chain isn't wore too bad you could try to shorten it. I would try to avoid half links if all possible but that size machine you might be fine. If you do replace them I would measure the chains and get a single roll then feed them through and cut it to length not the length of the old onesIt could also mean that some where in the past someone replaced the chain with the wrong size. So far I have asked in a number of posts about the OEM chain size and no one has offered the information....I am not willing to spend hundreds on replacement drive chain and have it maybe be the wrong size...
