Putting a hydro cooler on Exmark.

Discussion in 'Mechanic and Repair' started by Jason Pallas, Mar 11, 2008.

  1. Jason Pallas

    Jason Pallas LawnSite Bronze Member
    Messages: 1,335

    I've just finished installing a powersteering cooler on my 2000 Dodge 1500 (used for plowing). It got me thinking.... cool fluids are almost always better. Do you think it would be a good idea to install a tranny cooler (inline in the hydro system near the resevoir) on my Exmarks?
    It's certainly simple enough (just a little plumbing) and it could really keep fluid temps down.

    BTW- I don't have any hydro probs now - just thinking of ways that might benefit me further on down the line. Thanks for your input.
  2. Restrorob

    Restrorob LawnSite Fanatic
    Messages: 11,029


    I'm not familiar with the Exmark line, I have only worked on a couple that were non-hydro related.

    But, I don't believe this could be done unless the hydro tank/wheel motors and pumps have provisions for low pressure lines.

    Below is a pic of a Dixie Chopper X2503 with a cooler, Note the solid black lines are high pressure hoses and the broken black lines are low pressure 3/8" clear plastic hoses slid over barbed fittings with spring clamps.

    If Exmark does have a unit with a hydro oil cooler it would be a good idea to look at it and see how it is installed.

    I don't believe it would be a good idea to cut and splice into larger high pressure hoses, Then wonder if the cooler can handle the pressure.

    Just my [​IMG]

  3. tomo

    tomo LawnSite Senior Member
    Messages: 660

    Yes a high pressure cooler is possible but not required
    A cooler mounted in the retun line [low pressure ] is the best
    Hydraulic system consists of
    suction line =resivour to pump
    high pressure line = pump to wheel motor
    return line low pressure wheel mtr to resivour
    --- the filter is also mounted in this line

    mount cooler in the return line

    points of note
    cooler selection is critical ,not only for its cooling capacity but pick the wrong type and u might 1/ spend to much $
    2/restrict flow causing failure to hydraulics
    3/ to big will not cool .[flow is to small ]
    3a / A very large cooler will increase warm up time 4 the system
    4/ to small will not cool
    5/ mount incorrectly and it will crack
    6/pick the incorrect type and the fins will fill up with grass =heat rejection will then stop

    selection of a cooling fan is critical
    coolers *** do not*** perform without a fan

    Restorob is correct ,using the dixie brand as an example is ok
    Kohler use the same brand of coolers as dixie but a different type
    Both kohler and Dixie mount the coolers in the air flow supplied by the engine fan [air cooled ] This is not recommended as u remove the heat into the air used 4 engine cooling :hammerhead::hammerhead:U will not gain a lot of benefit by doing this

    The brand of coolers is "Long industries"" parent company is Dana . Look under either on the www
    Recommend the alloy stamped plate type approx 12x 12 inches 1 1/2 thick
    It is classed as a heavy duty trans / engine oil cooler . A BSP fitting is at either end to allow 4 proper fittings

    Use all correct hydraulic fittings . Hose clamps are not to be used.

  4. JimQ

    JimQ LawnSite Bronze Member
    Messages: 1,139

    Tomo - you're close and have provided some good general info but...

    There are no "low-pressure" or return lines from the wheel motors.

    Only 2 pressure lines. Forward/Reverse. It's basically a closed loop. That's why pump mounted fans are so much more effective in this type of a system

    Some wheel motors may have case drains but these do not.

    Typically on a Z, the cooler is added into the system after the case drain of both pumps and before the reservoir.

  5. tomo

    tomo LawnSite Senior Member
    Messages: 660

    hello, Jason
    Have a look at the toro 597 diesel [a cooler is installed in the radiater ]
    It would be a good example as i suspect the hydraulic systems to be similar in design .
  6. Jason Pallas

    Jason Pallas LawnSite Bronze Member
    Messages: 1,335

    Thanks guys for some really good info and suggestions. I was actually able to talk to the Exmark rep today (caught up with him at an open house at a local shop). He explained to me that installing a cooler in the low pressure side (near the resevoir) would only cool 15% of the fluid in the system.
    The other 85% in the system is in high pressure circulation between the two hydro pumps and wheel motors and to be able to cool this I WOULD NEED to hook into the high pressure side. As Tomo points out, this would be possible but expensive and probably very problematic.
    Thanks Rob, Tomo and JimQ - appreciate the help.

Share This Page