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Bobcat S250 Drive Noise

EZ-Man86 · 2024-03-26 15:13

Hey guys, Was running my S250 a while ago and it started a "clacking" kinda sound whenever left stick was engaged.. Also noticeable power loss on that side. Ideas on what to look at? I have the cab off right now doing a swap so anything else maintenance I should do while in there I am all ears. Thanks a bunch EZ

Replies42
  1. #1Coaldust2024-03-26 16:40

    I can hear it, too. It sounds expensive. Jack the left side off the ground and check for movement. You are allowed 1.5”. That will give you an idea of drive chain condition. Then, you can go from there. Let us know. Broken axle hub, failed bearing, drive motor is toast,……. $$$$$$ oh’ boy.

  2. #2EZ-Man862024-03-27 09:36

    Lol thanks for the non-Inflammatory prognostication. I have all 4 wheels off and sitting on blocks.. Can not get much if any movement out of the hubs.. Will put a couple wheels back on and let you know what I get. EZ

  3. #3Coaldust2024-03-27 13:11

    The next easy check is to remove the left side drive motor case drain filter and see if the canister is full of junk.

  4. #4EZ-Man862024-03-27 13:23

    Is that the Black cover right in between the axles? EZ

  5. #5Coaldust2024-03-28 00:14

    Roger that. Be prepared to make a mess. I’d have a new filter handy in case you wish to replace it.

  6. #6Skid-steer Repair2024-03-28 18:07

    Just remember some of those case drains, depending on model, returns directly to the reservoir. Which means before you remove it you should drain the reservoir or expect to have several gals of hydro filling your chassis. -as for the clicking, most likely the chains, sprockets, and bearings. The power loss could be drive blew a seal.

  7. #7EZ-Man862024-04-01 09:21

    So I have next to no play in the wheels.. Got my hydraulic oil drained and lines removed from my case drain filter.. Off to get some crows foot wrenches so I can get the filter out. EZ

  8. #8EZ-Man862024-04-01 11:24

    Well... Got my filter out... Full of silver shiny flakes and particulate... Assume its safe to surmise my drive motor is toast? Right hand filter is squeaky clean.. EZ

  9. #9EZ-Man862024-04-01 11:47

    Brass and silver actually EZ

  10. #10IceHole2024-04-01 12:09

    From mammary, there's just 1 case filter, both drives hook into it. Mine was clean with ~5000hrs on the machine.

  11. #11Coaldust2024-04-01 12:55

    Can you post a picture?

  12. #12EZ-Man862024-04-01 14:20
  13. #13EZ-Man862024-04-01 14:23

    So yeah i realized that both final drive motors drain to the one filter.. also the case drain from the aux at the bucket goes through an identical filter before then also coming to the one with both drains from the finals. Wondering what else to see before pulling motors? EZ

  14. #14EZ-Man862024-04-01 15:32

    Is it strange that I don't have any debris in the case drain hose or fitting from my weak motor? EZ

  15. #15Skid-steer Repair2024-04-01 16:37

    There is no brass in the drives so I would say your hydrostatic pumps are shot. They are piston pumps with brass slippers on the end of pistons. Engine must be removed to replace. Sadly with that much debris your gear pumps are probably shot too.

  16. #16EZ-Man862024-04-02 06:32

    Well poop

  17. #17EZ-Man862024-04-02 09:03

    Would I confirm by inspecting my main hydraulic filter? EZ

  18. #18EZ-Man862024-04-02 09:39

    Also is it possible that the clacking I was hearing was coming from my Hydrostatic pump?

  19. #19Coaldust2024-04-02 09:42

    Hopefully the case drain caught caught the major debtis before it had the chance to cycle through the pumps and the main filter on the return side, but yes. Go ahead and check it. You’ll be changing the hydraulic oil anyways, before this project is done.

  20. #20Coaldust2024-04-02 09:46

    Perhaps. That just sucks, anyway you look at it. Probably didn’t have catastrophic hydraulic failure in mind, on your 2024 bingo card.

  21. #21EZ-Man862024-04-02 11:12

    Yeah wasn't really hoping to be getting this deep right now.. When I drained my hydraulic oil tank i did not notice any glitter.. After looking at it again and watching some of @howididit's vids on YouTube I am fairly certain that what I am looking at is brass from the slippers and the thrust washer.. kinda hoping against hope that my final drives might be ok, or just in need of a reseal..

  22. #22Coaldust2024-04-02 11:16

    In a closed loop system like that, the drive motors will digest everything the pumps serve them. The drive motors will eventually destroy your new pump.

  23. #23EZ-Man862024-04-02 11:43

    Possible that I could just do a cleaning and resealing though? Getting ready to go pull the engine.. Any tips? Thanks again for all the help EZ

  24. #24Skid-steer Repair2024-04-02 15:06

    Of course your main filter and your fan filter will be full of gold and gray glitter. If the hydrostatic pump is the source it’s all coming apart anyway. The real test is to dead head the pump and the expectation is for the engine to stall. Yours won’t stall on the weak side. However it would suffice to say if you dump out your filters and it looks like a pan of gold start taking the engine out.

  25. #25Skid-steer Repair2024-04-02 15:12

    This is not entirely accurate. Many bobcat hs pumps will case drain the debris and the filters catch most of it. As the brass breaks off the piston it falls to the bottom the hs pump and is case drained away to the cooler then then filter. A piston pump cannot “pump” if it has no brass slipper so it’s not delivering the “bulk” of the debris to the drives. It is likely his drives can survive this and NOT destroy his new pump.

  26. #26EZ-Man862024-04-02 17:23

    Main filter looks clean! I had previously drained the hydro tank and can not see any flakes in the oil. The outlet of the case drain filter looks clean too..

  27. #27Skid-steer Repair2024-04-02 17:31

    I quoted the wrong thing above. My bad. Basically I do not believe your drive motors will destroy your new pump like another post said.

  28. #28ozarkag2024-04-02 19:13

    Only if ALL debris is removed from system. Likely entails disassembling drive motors. At this point I would likely start disassembling the pumps and motors. Cleaning, repairing, rebuilding or replacingas needed.

  29. #29EZ-Man862024-04-02 19:36

    Yeah I'm going to start pulling the motor in the morning, so I can go get at the hydrostatic pump. Hoping it's just one side that failed. Then I would only have to potentially do one final drive? Definitely deeper than I wanted to get on this project but it's good opportunity to fix everything.

  30. #30Skid-steer Repair2024-04-02 19:48

    Your pump didn’t likely send debris to your drive motors. That case drain you showed earlier is it shared with your hs pump case drain? I think so. What is your serial and I will get the diagram. The “case” portion of your left hand HS Pump is common with the “case” section of your right hand HS Pump. All of this goes back to the filters before it is sucked up by the charge pump, filtered again at the fan, and redelivered to the HS Pump. Now with a damaged Hs pump there is massive internal leakage. So the charge pump is now flushing the HS Pump over and over to remove debris back to the filter. Not necessarily to the drive motors.

  31. #31EZ-Man862024-04-02 20:08

    I'll get you my serial number in the morning.. 3 lines on the inlet of the case drain filter.. 2 from the final drives and I am pretty sure the other is coming from the auxiliary at the attachment point

  32. #32EZ-Man862024-04-03 09:33

    Serial is 530940001

  33. #33EZ-Man862024-04-04 10:18

    anyone able to tell me what size caps and plugs I will need for the hydraulic lines I need to disconnect in order to pull engine? Thanks in advance. EZ

  34. #34Skid-steer Repair2024-04-04 11:43

    All JIC, 4,6,8,10,12, maybe 16. You will need at least 4 each of #12 and #10. The others 2 each should do. Buy a couple Amazon kits.

  35. #35EZ-Man862024-04-21 16:11

    Hey guys, So I got the engine out and Hydrostatic pump off.. Pulled the left side apart and this is what I am seeing.. Never seen the inside of one of these, but this is not looking to me like catastrophic failure.. I was expecting the thrust washer to be gone.. There is clearly wear on the piston faces but the scratches are very sallow.. wondering if this is looking like just re sealing this and tearing in to the drive motor? Wondering if the little gold I saw was my minimal piston wear and the rest was from a final drive? Regardless I'm glad I pulled the motor based on some other discoveries.. Thanks in advance. EZ

  36. #36EZ-Man862024-04-22 10:30

    Here are a few shots of the trust plate on the second pump.. As well as the piston wall. There is some reflection in the pic, but the thrust plates feel smooth and only a slight "cloudy" strip around the rim.. The fit on the pistons of both pumps is tight.. No slop whatsoever.. Like I said, I am not familiar with these but nothing I am seeing is saying failure to me. Minor to moderate wear yes, but to failure. Also whatever you call that plate in pic 4 of my last post, the one under the piston block has some very minor scratches, but no grooving. Can not even catch my nail on anything.. Going to set these aside and check my left hand drive motor. Any help greatly appreciated. EZ

  37. #37EZ-Man862024-04-25 09:53

    Anyone out there? Seems like the site has been down a lot lately.. So I was surprised to find brass inside my final drive... Anyhoo this journal bearing has a pretty deep spiral groove in it.. Is this normal? It seems to be a consistent spiral which leads me to think it is intentional so that the bearing can stay lubricated? Couple of seals throughout the drive that look worn. Nothing catastrophic.. I had oil outside of my brake section which tells me that that seal was shot.. I can see seal material inside the brake chamber.. All the brake disks look fine, no wear that I can discern. So now I am getting confused.. Where did all the material in my case drain filter come from? All I have encountered so far appears to me, to be very normal mild wear. Hoping for some solid intel or advice before I pull my other drive.. Was having no issues with that side, but could it be that that drive dumped all the debris into my case drain filter and for some reason my left side was the only one with noticeable power loss? Grasping at straws here guys. Any help greatly appreciated. EZ

  38. #38EZ-Man862024-04-25 15:23

    https://www.etsy.com/listing/1398939037/s250-s300-skid-steer-loader-workshop?show_sold_out_detail=1&ref=nla_listing_details For anyone interested, I bought this service manual for $7 and its legit.. EZ

  39. #39Skid-steer Repair2024-04-27 12:02

    Does your valve plate have a brass/copper color on side or is it all steel/gray?

  40. #40EZ-Man862024-04-27 13:50

    Copper or brass just like that on the one side

  41. #41Skid-steer Repair2024-04-27 14:11

    Can you call me?

  42. #42EZ-Man862024-04-28 09:36

    Will do.. EZ