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mm2 very slow

Discussion in 'Fisher Engineering Discussion' started by bill2it, Feb 12, 2015.

  1. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    I have a 6 yr old mm2. Didn't use for two yrs. Installed on 2004 GMC 2 weeks
    ago. Replaced motor and motor relay (motor was seized). Cleaned and lubed
    all connections. New Fisher fluid and filter. First time operating plow seemed
    fine, then started operating slower and slower until wouldn't work (motor was
    turning, drawing lots of power just not enough to move blade). Middle of two
    foot snow chain lifted blade, limped home, next morning plow lifted fine. Another two feet of snow same thing worked for an hour then died. Lights
    work jiggled wires on plugs re-cleaned and re-lubed plugs and connections
    still having problems. Any ideas?
     
  2. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,005

    Have you looked at the fluid? I'm thinking frozen, filter clogged.
     
  3. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    Changed fluid with Fisher fluid and new filter. There was some moisture in
    fluid but filter wasn't bad
     
  4. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,005

    And you drained the angle rams to?
     
  5. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    drained everything
     
  6. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,005

    So after the drain and fill (to the proper level of course) it's still acting up.

    What's the volts reading while this Is happening? Actual numbers, not dash gauge.
     
  7. NHresident

    NHresident Senior Member
    Messages: 285

    when u drained it did u take the unit to a bench and took the can off to chk the filter? IF u didnt u really should chk the filter IF u can get the 2 mounting manifold bolts out
     
  8. superdog1

    superdog1 Senior Member
    Messages: 256

    I agree with this. Besides having water in your pump, it will also slow down and get slower if your voltage and amperage drop. It sounds like your battery and alternator can't keep up with the plow and after using it awhile, it just quits because it has no reserve left in the battery. When you stop using it and drive home, the system gets recharged enough to work the next day until it starts all over again.

    Once you get below around 9.5 volts or so, it will just stop working.:rolleyes:
     
  9. caboman

    caboman Junior Member
    Messages: 17

    I agree, you probably have beacons and lights on also?
     
  10. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    I did take can off when I changed fluid. Cleaned magnet, inside and top of can to remove little
    bit of rust. After replacing filter and o rings checked old filter - wasn't bad, very little dirt. Also
    cleaned return screen assembly which had fallen off. Did have problem with stripped positive
    battery terminal but replaced battery with new one. I wasn't able to check voltage while operating
    because I was by myself. It did draw a lot of juice while operating but the charging system handled
    it. I'm thinking my next move is to check the pump itself.
     
  11. superdog1

    superdog1 Senior Member
    Messages: 256

    With all due respect, you are contradicting yourself, Lol. You mention that you couldn't check the voltage, yet you claim the charging system handled it. How do you know this? Even if you have a gauge in the dash of your truck, they are semi-worthless for the most part, as they do not read the exact voltage but give you a general idea of what is happening.;)
     
  12. mrv8outboard

    mrv8outboard Senior Member
    Messages: 197

    One must verify the voltage as it not being the issue. But lets say that the voltage is fine, there are two thing that mimic these symptoms to a point. Check the pump pressure. I had one that it was find and quickly slowed operational speed then power to lift in a pile. Tested and found the pump pressure at 600, not good. I adjusted the pressure quill and set the pressure back to 1800 (just a 1/4 turn) and it has been fine since. The other thing is the pump itself. Had another one (EZ-V) that was slow and weak. tested the PSI and it was 400 and I could not get the PSI ant higher adjusting the quill. Installed a new pump and bingo 1800 PSI and works great.

    On a side note multi function plows will malfunction with low pressure. I mean that commands from the controller will not equate to plow function. Up will Vee and wing will not work right, all this is due to lack of pressure.

    So just make sure you have enough pressure with enough voltage.
     
  13. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    What I meant was the truck's charging system didn't seem to be affected by the heavy
    voltage draw from the plow. I know the plow is drawing way more power than it should
    but I'm beginning to think as mrv8outboard above said that the pump is not putting out
    enough pressure. Anyway its time to bundle up and get to work. 13 degrees and the wind
    is whipping in from the ocean.
     
  14. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    new pump everything works
     
  15. superdog1

    superdog1 Senior Member
    Messages: 256

    Good deal! With over 80" of snow in the last 3 weeks, the last thing you need right now is plow issues!!!:drinkup:
     
  16. bill2it

    bill2it Junior Member
    from hull,ma
    Messages: 7

    More this weekend. Thanks to everyone for the help