Bobcat 743 Drive Motor Teardown

[gatorguy]

Hi there,
Long story short I got my gear pump working (wafer plates needed sanded) and got the skidsteer out for a test. Was working great drive wise except when going full speed it would "pop" but keep driving. Then after working with it for awhile I went to do a 360 and the right side drive just "popped" when power was applied. So I tested it on flat concrete almost at idle. The right side would stay still and the other side would do the turning. I could still drive it around, it just didn't want to work properly. Loaded it on the trailer, brought it home. Couldn't replicate the problem. So now i came to think it is a hydraulic issue since it only when the fluid was hot and thin it would do this, rather than a chain case issue. I did jack it up and I have about 3/8" average amount of play per chain. (I had just done new chains, bearings, seals anyways.) So I swapped drive motors and tried to get it up to temp again, problem was not as bad on the left side now but could still get it to pop. I wasn't running it for as long anyway.

Anyway, took apart the motor and while there are no cracked seals, the geroler rotating group doesn't look very healthy. Pitting on the rollers and can easily turn the assembly so it isn't super tight. Also weird divots on he ends of the rollers and scoring in roller slots and on the plate.

My question is, is this too much wear? Could I put a seal kit in it and perhaps be ok or is this Geroler rotating group too far gone?

[IMG alt="https://ibb.co/BtHZpFF
"]https://i.ibb.co/rmK6jNN/20210113-132243.jpg[/IMG]

Thanks in Advance!

 

[Wayne440]

I claim ZERO expertise - but to me that looks like damage due to something in the fluid (metal particles, grit, sand, ???) rather than just "too much wear". My guess is that you will end up replacing it. Others with relevant experience should be along later, please post up what your eventual solution is.

 

[gatorguy]

I claim ZERO expertise - but to me that looks like damage due to something in the fluid (metal particles, grit, sand, ???) rather than just "too much wear". My guess is that you will end up replacing it. Others with relevant experience should be along later, please post up what your eventual solution is.

Yeah, I'm pretty sure its shot and I'm sure after 40 years it has got some grit in the system! Its new to me...bought as a project. Bobcat warehouse doesent sell gerolers and Eaton is 12 weeks out. Bobcat is out of drive motors too...$2900 a piece if they did have them. Ill have to start shopping at some of the places in the US with reman motors. Can't be paying that kind of money. Would be awesome of a seal trick did the trick for a season but with no cracked or broken seals i don't know that it would.

 

[Tazza]

Yeah, I'm pretty sure its shot and I'm sure after 40 years it has got some grit in the system! Its new to me...bought as a project. Bobcat warehouse doesent sell gerolers and Eaton is 12 weeks out. Bobcat is out of drive motors too...$2900 a piece if they did have them. Ill have to start shopping at some of the places in the US with reman motors. Can't be paying that kind of money. Would be awesome of a seal trick did the trick for a season but with no cracked or broken seals i don't know that it would.

All it would take is a small piece of metal to come off and it will jsut keep rubbing where the geroler star sits and wear the face like that.
I wonder if you can get a shop to surface grind it to make it seal right and put a new geroler into it.
Loader parts source may have an option for you too that isn't stupid expensive.

 

[gatorguy]

All it would take is a small piece of metal to come off and it will jsut keep rubbing where the geroler star sits and wear the face like that.
I wonder if you can get a shop to surface grind it to make it seal right and put a new geroler into it.
Loader parts source may have an option for you too that isn't stupid expensive.

I called my local bobcat dealer and they said the Gerolers were obsolete and that a new drive motor was even out of stock from Bobcat and if they did have it, it would be $3k! Since it is an Eaton/Charlynn motor called a local hydraulic shop that does eaton and he said normally the price of gerolers writes off the motor. He said he also was getting 12 week lead times for these parts...all thats available to mehere locally is the seal kit at $160 in two weeks... I would love to rebuild this one but isnt looking possible unless I can find a reasonably priced geroler. I believe reman drive motors are around $1200 US

 

[Tazza]

I called my local bobcat dealer and they said the Gerolers were obsolete and that a new drive motor was even out of stock from Bobcat and if they did have it, it would be $3k! Since it is an Eaton/Charlynn motor called a local hydraulic shop that does eaton and he said normally the price of gerolers writes off the motor. He said he also was getting 12 week lead times for these parts...all thats available to mehere locally is the seal kit at $160 in two weeks... I would love to rebuild this one but isnt looking possible unless I can find a reasonably priced geroler. I believe reman drive motors are around $1200 US

Contact loader parts source, they are one of the best out there to be able to source parts for pumps and motors for skid steers.

 

[gatorguy]

Contact loader parts source, they are one of the best out there to be able to source parts for pumps and motors for skid steers.

Thanks. Ended up just ordering two from Stoens hydrostat. $735 US and they take the core back...about a third of the cost from buying from bobcat so got two since they both look original.