Great info on this site - now I'm looking for some direct guidance. sorry for the format can't seem to put paragraph breaks...................... 1989ish Bobcat 843, hydraulic oil flooding the chain case. pulled drive motors, LH side carrier seal had a gap at the input shaft on the gear case and that input shaft had tons of play. Popped chain case cover and could see the bearing basically falling out at the input shaft inboard of the gear case................ I popped off the carrier seal and it seems that the outer bearing on that input shaft is totally blown and that whole shaft is wobbly. I'm trying to do this without dismantling too much, but it seems I certainly have to take off the gearbox to replace the bearing(s) and assess the damage................ is there a way to pop that gear case off without breaking any chains? No master link that I see and I don't have a chain breaker. The service manual says to remove the front chain............. Should I be worried about other bearings? wheels seems tight and the other side carrier shaft seems tight. The chain case cover gaskets are getting bad so there was probably water in there but the previous owner was running it until he was getting drive issues on the LH side............ Any tips or other things I should look for? I'm certainly in unfamiliar territory here but rolling with it and feel pretty confident moving forward. Thanks for any help
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Here's a little update & quick followup questions:
From photos of gearboxes it seems there are 5 bolts that are accessed from the inside. Any way to get these off without removing the rear chaincase cover?
Should I just drop the chaincase and deal with all this directly? Not Ideal... Or is it easier to lift the pump out? The RH side seems to be fine and the wheel bearings seem fine. Not sure what would have caused this damage Here are a couple videos:
https://youtu.be/7Ar4L-evom4
https://youtu.be/t2E1orL6VAM
In the second video it looks like the output shaft bearings are blown too
From photos of gearboxes it seems there are 5 bolts that are accessed from the inside. Any way to get these off without removing the rear chaincase cover?
Should I just drop the chaincase and deal with all this directly? Not Ideal... Or is it easier to lift the pump out? The RH side seems to be fine and the wheel bearings seem fine. Not sure what would have caused this damage Here are a couple videos:
https://youtu.be/7Ar4L-evom4
https://youtu.be/t2E1orL6VAM
In the second video it looks like the output shaft bearings are blown too
I'll just keep updating with progress
decided to go the route through the top instead of dropping the chain case. Pulled the Hydraulic pump and weasled out the second chain cover. Looks like I'll be able to reach all the bolts on the gearcase, and I'll probably cut the chain and buy a new link
popped the seal on the output shaft and found all my bearings! Anyone know what might've caused this failure? Previous owner had repaired both drive motors 2 hrs ago but didn't notice it sucking hydraulic fluid into the case. And I haven't used it at all, just transported it to my place.
I guess I can take it from here but welcome thoughts or advice. i'll keep updating with progress for reference
I would think that the condition of the oil did not help with the wear.
So you took the front pump out,how was that to do,how did the rest of the repair go?I'll just keep updating with progress
decided to go the route through the top instead of dropping the chain case. Pulled the Hydraulic pump and weasled out the second chain cover. Looks like I'll be able to reach all the bolts on the gearcase, and I'll probably cut the chain and buy a new link
popped the seal on the output shaft and found all my bearings! Anyone know what might've caused this failure? Previous owner had repaired both drive motors 2 hrs ago but didn't notice it sucking hydraulic fluid into the case. And I haven't used it at all, just transported it to my place.
I guess I can take it from here but welcome thoughts or advice. i'll keep updating with progress for reference
I haven't had to go this deep, but did park on a steep slant to help the accumulated dirt and water to pool in one corner, then siphoned, pumped and hoed it out. Crazy design with no filtration on the breathers. Amazing these machines tolerate this lubricant condition for years and still move. I appreciate your ongoing updates--Thank you. Can you say anything more--its been a long time.
Since you suspect water intrusion, inspect other bearings for signs of wear or corrosion. It's wise to replace any questionable bearings while the gearbox is accessible. Replace the chaincase cover gaskets with high-quality parts to prevent future leaks and water damage. Consider using this experience as an opportunity to perform a more comprehensive inspection of your Bobcat's drivetrain and address any potential issues early on.
