Results 1 to 13 of 13

Thread: Kubota LA350 Loader Hydraulic Issues

  1. #1
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default Kubota LA350 Loader Hydraulic Issues

    I've got a B2150HSD with an LA350 loader. Nothing big and fancy, but it gets the bush hogging and dead log hauling done around here just fine with very few issues over the years.

    Tractor is now about 25 years old, and the hydraulic hoses and filter were last changed in 2008. The hydraulic control valve unit was changed out a few years before that under a warranty swap.

    I lost my 'bucket float' a year or so ago, and just recently I've pretty much lost the ability to raise the bucket.

    The hydraulic fluid levels are fine, the connectors are tight, I've removed and reconnected the two quick disconnects on the delivery hoses just to make sure something wasn't stuck in them, etc. There are no hose leaks anywhere.

    I'm assuming that I should be pulling the hydraulic valve control block and change out all of the seals and o-rings, etc, but didn't want to jump to that conclusion until I checked with some of you who know a lot more about these thing than I do.

    Ideas? Things to check first? Suggestions, other than taking it in to a dealer or mechanic right off the bat since I need to do as much of the work myself as I can handle.

    Thanks.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  2. #2
    Join Date
    Apr 2009
    Posts
    1,111

    Default

    I’d start by changing the hydraulic filter that’s 11 years old.
    "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian" - Henry Ford

  3. #3
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Quote Originally Posted by Fowlmouth30 View Post
    I’d start by changing the hydraulic filter that’s 11 years old.
    No question that's on the list. I may have changed it since 2008, I just don't recall doing it.

    But would a partially plugged filter cause just the float and lift functions to stop vs everything, understanding that the 'dump' functions are low pressure?

    Also note that the 3-point hitch has not been affected, at least not yet.

    Just trying to break it down and trying to understand it so I can knock out the work, hopefully, in one session vs going back time and time again trying different things, especially since I don't have that great workshop that you do.

    Thanks.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  4. #4
    Join Date
    Jun 2010
    Location
    charleston
    Posts
    8,600

    Default

    Probably a hydraulic proportioning valve- directs the flow as needed for the task selected. I had one go in one of my older Kubota mini ex's, some functions were fine others wouldn't work or were at a very reduced power.

    The 3 point and the loader are on different control levers- start at the lever and trace toward the bucket.

  5. #5
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Quote Originally Posted by Bad Habit View Post
    Probably a hydraulic proportioning valve- directs the flow as needed for the task selected. I had one go in one of my older Kubota mini ex's, some functions were fine others wouldn't work or were at a very reduced power.

    The 3 point and the loader are on different control levers- start at the lever and trace toward the bucket.
    I assume this means something like a leaking seal, etc, whereby removing the hydraulic valve control block and changing out the o-rings and seals (general rebuild) would probably be the right thing to do... along with changing the hydraulic filter. Yes... no?
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  6. #6
    Join Date
    Nov 2007
    Location
    In the bend
    Posts
    5,620

    Default

    First I would crack the lines at the bottom of your lifting cylinders to see if you are getting flow.

    If you are getting flow then you are either not getting enough pressure there or your cylinder packing is leaking by pretty good. If you are getting pressure, you can you install an in-line pressure gauge to see where you are.

    If you aren’t getting then you need to look at your valve block.

  7. #7
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Quote Originally Posted by b-stick View Post
    First I would crack the lines at the bottom of your lifting cylinders to see if you are getting flow.

    If you are getting flow then you are either not getting enough pressure there or your cylinder packing is leaking by pretty good. If you are getting pressure, you can you install an in-line pressure gauge to see where you are.

    If you aren’t getting then you need to look at your valve block.
    OK, easy to check the cylinder flow. As for the pressure gauge, what kind of psi does it need to read, since I'd guess it's much more than the gauges I have around the workshop?

    Thanks.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  8. #8
    Join Date
    Nov 2007
    Location
    In the bend
    Posts
    5,620

    Default

    I would just get a liquid filled 5000psi gauge.

  9. #9
    Join Date
    Aug 2009
    Location
    On the Right Side of the Grass
    Posts
    48

    Default

    You can swap the bucket lines with the lift lines and that should tell you if it is a cylinder or the valve. Just went through this. Got lucky. Pulled the valve and cleaned it all out and she went back to work. Must have had some trash in the valve body.

  10. #10
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Quote Originally Posted by b-stick View Post
    I would just get a liquid filled 5000psi gauge.
    Do I need to: a) put in inline at the bottom of the cylinder with a T fitting, or b) just attach it to the hose to get a reading without the cylinder connected? I'm guessing 'b' is fine, but correct me if I'm wrong. And although I might find it in my Kubota manual somewhere, what kind of pressure should I bee looking for?

    I'm guessing that if I have about the proper pressure, then I need to look at rebuilding the cylinders.

    But the cylinder question doesn't address the float, so unless the control valve unit itself is in need of a rebuild, that's a separate issue.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  11. #11
    Join Date
    Nov 2007
    Location
    In the bend
    Posts
    5,620

    Default

    I would put it in line.

    Crowd is right also. You can swap the lines at the valve body and check it that way. I don’t know why I didn’t think of that.

  12. #12
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Quote Originally Posted by Crowshill View Post
    You can swap the bucket lines with the lift lines and that should tell you if it is a cylinder or the valve. Just went through this. Got lucky. Pulled the valve and cleaned it all out and she went back to work. Must have had some trash in the valve body.
    Good thought. I'll take a look at that. Thanks.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

  13. #13
    Join Date
    Mar 2002
    Location
    'Down in the Holler', SC
    Posts
    14,554

    Default

    Update in case it helps someone else...

    Rather than pull any lines, yet, and after talking to one of the tech guys at Messicks.com (they've got parts and schematics available for all brands of tractors and generators, etc), I first removed the caps on the forward edge of the hydraulic block. One is for the bucket valve controls and the other is for the bucket 'float'. Both include a large spring (they don't come off as they are attached to the end of the control rods) and they were both pretty dried out and dirty. After cleaning and brushing the rust off with a brass brush, and adding a good dose of red grease, the movement of the controls greatly improved.

    The float still doesn't work as the two ball bearings were rusty and I couldn't find the right size (3/16" or .1875) bearings in my parts bins, and didn't have any BBB or T steel shot to try, so I just cleaned up the old ones for now, but the rod they work against probably needs replacement also.

    Fowlmouth30, yes, I did change the hydraulic filter. Fortunately everything still looked pretty good so I hopefully didn't do any damage by waiting so long.

    I still need to clean the transmission strainer, just because its due, but the mechanic recommended I wait until I change the hoses so as to not open up more of the system than necessary. So the hoses and strainer are a job for sometime in the future, along with changing the fluid.

    Thanks for your other suggestions. I, or someone, may need them in the future.
    .
    Foothills Golden Retriever Rescue
    .
    "Keep your powder dry, Boys!"
    ~ George Washington

    "If I understood everything I said I'd be a genius." ~ 'Unknown'

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •