1. Welcome to PlowSite. Notice a fresh look and new features? It’s now easier to share photos and videos, find popular topics fast, and enjoy expanded user profiles. If you have any questions, click HELP at the top or bottom of any page, or send an email to help@plowsite.com. We welcome your feedback.

    Dismiss Notice

Intermittent hydraulic failure

Discussion in 'Truck & Equipment Repair' started by Bulldogtb, Feb 17, 2015.

  1. Bulldogtb

    Bulldogtb Junior Member
    Messages: 3

    I have a MM 1 SEHP and while plowing the other day the Blade would not lift or angle. Got it into the warm garage and in the morning it worked but after plowing for 20 minutes it failed again. This time the blade got 1inch off the ground but the plow would not hold an angle, it just freely moved back and forth. 4 hours later it worked again while I did a large driveway for 30 min. Left it outside this time and 6 hours later it worked for 5 minutes before the blade had no hydraulic pressure again. 2 hours later it appears to be working again. The motor is turning, and there is enough fluid (changed last year). I can't think of what would cause this intermittent loss of hydraulic pressure. I originally thought I had water in the system and it was freezing but that would not explain the free floating blade. Any input would be appreciated.

  2. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,391

    I'd Ck for freezing fluid to start with.
    Either drain it or pull the motor off.
  3. PLOWMAN45

    PLOWMAN45 2000 Club Member
    Messages: 2,951

    drop the bowl and change the fluid and install a new filter
  4. LakeCountySnow

    LakeCountySnow Junior Member
    Messages: 10

    Frozen fluid for sure.
  5. Ieatsno

    Ieatsno Junior Member
    Messages: 11

    An air pocket will cause this, I have the same issue, try burping the air out by removing the fill plug and cycle the controller. I just haven't had time to find how air is getting in the valve body and causing this issue. Last year i drained the system and put in super low temp oil so I don't think it is an oil foaming issue. There is just snotime to get anything done!!!