Leaky Hydraulic Drive Motors FIXED

[@AspenStumpRemovalIrwin-z2i]

Great videos man, thank you for walking us through this process!! I have the same Mini Skid Steer and both drive motors are leaking. Like yours, my outter seals appear to be shot, is it possible to leave the drive motors mounted in the frame pull that cover and replace the pressure seal, dust seal and o-ring ? I’m trying to avoid pulling both motors if I can. Thank you, Ben

[@reidthemanual]

@@AspenStumpRemovalIrwin-z2i Hi, Ben. If you wanted to purely replace the seals (without reconditioning the shafts), then, yes, you could remove the motor face plates, replace the pressure seal, dust seal, and oring and then reinstall the face plate. I’ll caution you on three things: 1. You may loose a lot of oil out the front of the motor if you remove the face without disconnecting the lines going to the motor. 2. Some owners online swear that you cannot replace these seals and get more than a few days work out of them, and I suspect that is precisely because they put new seals on damaged shafts. Some say it is because the motor internals/bearings are shot, but that was not the case during my rebuild. Just know that, if you change your mind, reconditioning the shaft will be difficult with the motor in the machine. 3. You really need to prevent dirt/debris from getting in the motor when you open it up. So, before you open it, clean the motor exterior and surrounding frame very, very well. Once you open it, you don’t want to brush against the machine’s fuel tank and see dirt fall down on the now-vulnerable motor internals. All that being said, I wish you luck in your repair and am glad to answer any questions that come up.

[@AspenStumpRemovalIrwin-z2i]

Thanks for the detailed reply…all fair points made here. I see why you went the extra mile using the shaft sleeve…if your this far into it it just makes sense. Thanks again.

[@AspenStumpRemovalIrwin-z2i]

How have the sleeves held up for you? Any subsequent leaks/issues?

[@reidthemanual]

@@AspenStumpRemovalIrwin-z2i So far, I’ve not had any leaks since doing this rebuild and changing the hydraulic fluid. This machine is for personal use, so I’ve only put about 50 hours on rebuilt motors, but some of those hours were working the machine pretty hard ripping out roots. All told, I’m very happy with the repair sleeves.

[@miltechmoto]

Have you tried at 205 for something like this?

[@reidthemanual]

Interesting. I had never heard of AT-205. It sounds like some other “stop leak” products I’ve used though. Have you ever used it in hydraulic motor applications? The manufacturer mentions hydraulic cylinders but not motors.

[@miltechmoto]

@reidthemanual it's one of the better kinds of seal conditioners from what I hear. It's not supposed to swell seals as it's polymer based product, not a petroleum product. I've used it on a few things as preventative maintenance to prevent seals from hardening. Just don't add too much or use it on new seals. I had a buddy use it on a diff and the seals started to leak, most likely from adding too much for seals that are calibrated to be hard to hold in the heavy weight dif oil. So less is more as he found out. But yeah you could give it a try. I'd imagine for the hydraulic system you'd only need a teaspoon or 2 to be within spec. Kinda like water wetter. Start with the minimum and see if the leak stops and then go up from there.

[@337aii]

What brand is that drive hydro motor, I have a similar problem, it has thrown out the ring on the engine cover twice in a short time.

[@reidthemanual]

Hi there. The motors in the video are Danfoss TMKW 315 wheel motors.

[@337aii]

Okay. Thank you for your reply. The only problem for me is that it breaks out on the ring.

[@reidthemanual]

@@337aii what type of machine are you working on?

[@337aii]

@@reidthemanual Chinese mini excavator NEX N12

[@reidthemanual]

@@337aii That looks like a cool little machine. Are you staying that the rubber-and-metal hydraulic seal is being pushed out the end of the your drive motor (the hydraulic motor inside your track behind the drive sprocket) and that is causing oil to leak out?