Hydraulic motor, no drive right hand side

[skidsteerdan]

Hello, I posted previously about bearings, seals etc for my 443. I fixed it all and have put nearly 200 hours on the loader since. Recently, it failed just after reversing up a modest hill, with nothing in the bucket. The right hand wheels would not turn at all, only left worked. I diagnosed it as the motor and just completed disassembly. I found that one of the springs that held the pin in place between the balance plate and valve housing has sheared, leaving the remainder of the spring in the shaft and some tasty metal filings strewn about. My question is one of what the heck would cause this? The machine is nearly 40 years old, so perhaps just fatique but I'm wondering if there may be another problem that cause this problem. I have a seal kit and will 4 replacement springs tomorrow, 2 for this motor and 2 for the other when I decide to re-seal that one.

 

[skidsteerdan]

Just thought I'd write with an update. I replaced most things in the motor, including the seal kit. I followed the instructions in the service manual carefully, especially for timing. I also used the instructions in the eaton 2000 manual, which were the same but better descriptions and pics. I couldn't get the motor to move even after re-assembly. I took it back apart, tried again and paid twice as close attention, still no rotation. I swapped motors sides and the problem follow the motor. I ordered a new hydraulic motor from LPS and it worked perfectly, back to driving now. There's another post on the forum with a similar motor and problem, I guess it was the worn splines on the inner part of the motor, which I did not venture into but I'm pretty sure mine were 100% good based on my feedback of turning by hand. Either way, I kept the old motor for parts or entertainment, whichever comes first I guess. FYI The LPS motor is a 100% Eaton motor and 100% new, not reman, not chinese ripoff, totally worth the big bucks. I was afraid I'd get some ripoff that I can source myself for $400. LPS has given me a lot of good parts, no complaints.

 

[Tazza]

Just thought I'd write with an update. I replaced most things in the motor, including the seal kit. I followed the instructions in the service manual carefully, especially for timing. I also used the instructions in the eaton 2000 manual, which were the same but better descriptions and pics. I couldn't get the motor to move even after re-assembly. I took it back apart, tried again and paid twice as close attention, still no rotation. I swapped motors sides and the problem follow the motor. I ordered a new hydraulic motor from LPS and it worked perfectly, back to driving now. There's another post on the forum with a similar motor and problem, I guess it was the worn splines on the inner part of the motor, which I did not venture into but I'm pretty sure mine were 100% good based on my feedback of turning by hand. Either way, I kept the old motor for parts or entertainment, whichever comes first I guess. FYI The LPS motor is a 100% Eaton motor and 100% new, not reman, not chinese ripoff, totally worth the big bucks. I was afraid I'd get some ripoff that I can source myself for $400. LPS has given me a lot of good parts, no complaints.

It's a shame your attempts of getitng your old motor working failed, i wonder what the cause of it is, for it to not move at all, i'd thoink you'd see something obvious.
I have never had issues with LPS parts either, they put their name to their parts, so they won't sell rubbish.

 

[skidsteerdan]

It's a shame your attempts of getitng your old motor working failed, i wonder what the cause of it is, for it to not move at all, i'd thoink you'd see something obvious.
I have never had issues with LPS parts either, they put their name to their parts, so they won't sell rubbish.

Well Tazza (Thanks for all of your help in holding up this community BTW, its one of the only resources I have). If you want my speculation, it's quite similar to this (which you also helped on): http://www.skidsteerforum.com/DesktopDefault.aspx?tabid=54&frmView=ShowPost&PostID=42516 - my 443 came with the "weaker" 2000 series eaton that he details. Except I did not have two symptoms: I did not have clicking noises (engine was pretty loud) and I did not clearly see any stripped gears, but I suspect that might have been it. Under no load (on stands) the motor would slightly turn the wheels but nothing else. Also I can turn mine by hand from one end of the motor and the spline turns on the other end, so it's not identical symptoms to SupermanSC's issues. However, SupermanSC says this motor of mine is known to have a weak spline and the 4000 series fixes that. I have kept the old motor so one day if I have too much time on my hands I will tear it back apart and look. My neighbor is a hydraulics expert but knew nothing of the motor so I might just take it to the bobcat dealer to troubleshoot. The other suspicion I have is that I just didn't get the timing correct - though my understanding is that if you don't get the timing correct the symptom would be the motor runs in reverse. If it's possible that with incorrect timing the motor has no power then that would lend credence to this. Since I know next to nothing about this, I'm only left with naive speculation. I expect this motor to last 35 years and someday maybe the other motor will go out and I'll have to do this all again.

 

[Tazza]

Well Tazza (Thanks for all of your help in holding up this community BTW, its one of the only resources I have). If you want my speculation, it's quite similar to this (which you also helped on): http://www.skidsteerforum.com/DesktopDefault.aspx?tabid=54&frmView=ShowPost&PostID=42516 - my 443 came with the "weaker" 2000 series eaton that he details. Except I did not have two symptoms: I did not have clicking noises (engine was pretty loud) and I did not clearly see any stripped gears, but I suspect that might have been it. Under no load (on stands) the motor would slightly turn the wheels but nothing else. Also I can turn mine by hand from one end of the motor and the spline turns on the other end, so it's not identical symptoms to SupermanSC's issues. However, SupermanSC says this motor of mine is known to have a weak spline and the 4000 series fixes that. I have kept the old motor so one day if I have too much time on my hands I will tear it back apart and look. My neighbor is a hydraulics expert but knew nothing of the motor so I might just take it to the bobcat dealer to troubleshoot. The other suspicion I have is that I just didn't get the timing correct - though my understanding is that if you don't get the timing correct the symptom would be the motor runs in reverse. If it's possible that with incorrect timing the motor has no power then that would lend credence to this. Since I know next to nothing about this, I'm only left with naive speculation. I expect this motor to last 35 years and someday maybe the other motor will go out and I'll have to do this all again.

My understanding for timing is taht they just run backwards too, not a power issue, which i find hard to understand, but i'm not an engineer.
I hope that getting timing spot on just means that fluid goes into port A rotation is in one direction, then port B it's the opposite on each and every motor, instead of a hook it up and see what whay it spins, then swap hoses if wrong.
It's never a bad idea to hold on to the old one just in case you need parts if the other one was to fail at a later date