Which way on a hill is worst on the hydro system??

Discussion in 'Lawn Mowing' started by johnwon, Jun 11, 2007.

  1. johnwon

    johnwon LawnSite Senior Member
    Messages: 299

    Does anyone know which is worst for the pumps and wheel motors....going straight up and down a hill or mowing across, or diagonal where you are mowing up and across at the same time. Thanks for any insight.
  2. mkroher

    mkroher LawnSite Senior Member
    Messages: 539

    Straight up a hill is the worst.

    But....straight up or diagonal on a slope is a lot safer than side to side. Well, with a ztr.

    Also, doing a 180 at top speed in a driveway when striping a lawn... is also the worst thing you can do to the pumps. 3 pt turns, adds life to the pumps. Ask any dealer.
  3. Scag48

    Scag48 LawnSite Fanatic
    Messages: 6,067

    Doing 180's is not going to blow up the pumps. They will indefinately last forever if you change the oil regularly and as long as they don't leak you're fine. The pumps and motors are pretty simple pieces, there isn't anything very complicated in the system. I will agree that going uphill is hard on the pumps, the wheel motor couldn't care less though. The pump takes the brunt of that as it's trying push the mower up the hill with a fairly hefty load.
  4. captken

    captken LawnSite Bronze Member
    Messages: 1,704

    I don't think it makes a difference either way. I got over 3000+ hrs out of the Hustler Z I have before I had pump/motor problems. I replaced the left side, the right side went out soon after.

    Hustler Z was new in 2001.

    I don't think hills affected the pumps as much as the other stuff I used to do with a mower....pulling logs, pulling trailer loaded with logs, spiking the pumps using the mower in things other than it's intended purpose.

    Check this out from 2005.


    I doubt any of you kiddies have done such a thing!
  5. johnwon

    johnwon LawnSite Senior Member
    Messages: 299

    I remember seeing that pic......you must of had some real good ones.
  6. johnwon

    johnwon LawnSite Senior Member
    Messages: 299

    I have read in some threads about some people mowing along the side of a hill where one wheel had most of the weight, and have them complain about a clicking or clattering sound. Anyway that didn't sound too good.
  7. Richard Martin

    Richard Martin LawnSite Fanatic
    Messages: 14,699

    It shouldn't make any difference unless there is a problem with the bearings inside the wheel motor to begin with. There generally isn't a "up" side to hydro motors and pumps. Now if you're hydro tank is low on fluid and the system sucks air while it's on a hillside, that could trash the hydros.
  8. lifetree

    lifetree LawnSite Fanatic
    Messages: 5,369

    Captken -- That is extreme, I'm impressed ... what ZTR are you using now ?
  9. Sammy

    Sammy LawnSite Bronze Member
    Messages: 1,734

    Worst ? ...............
  10. Pumper

    Pumper LawnSite Member
    Messages: 116

    As far as the hill, going up at an angle puts the highest pressure to one wheel. When one wheel is "higher" than the other on the hill, the "lower" wheel carries most of the weight and has to do most of the work. You will get your highest pressure spike on the hill when you are going accross the face and try to turn uphill. One wheel is doing all of the work.

    That being said, you will see spikes of close to 3,000 PSI. The pump is rated for 1000 PSI continuous and up to 3500 PSI peak (1% of the time).

    The highest pressure spikes will come when the wheel is trying to move while being "held". This occurs when you hit a wall, hit a curb, hit anything that stops the momentum of the machine while you still have the levers pushed forward. You can see spikes well over 4,000 PSI. You will see close to this when you do 180's on blacktop just because of the traction you get on blacktop versus on grass. Wheel slip is the easiest way to handle pressure spikes.

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