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Modifing bush hog from PTO driven to hydraulic .

BIGcatT870 · 2013-11-17 01:08

For quite sometime I have been wanting to convert a PTO driven bush hog With a hydraulic drive. The fabrication I can do . My problem is getting the correct hyd. Motor I have an older model 773 ( probably about an1997). It is not turbo charged. It's approx a 42 - 45 horsepower, 15 GPM and produces close to 3000 P.S.I. I'm not sure either what the max RPM for the bush hog. Thank you for you're time! Thank you for your time

Replies7
  1. #1Knocker of rock2013-11-17 01:13

    PTO's are either 540 or 1000 RPM for a rear driven implement

  2. #2JD88752013-11-26 19:10

    Check out www.surpluscenter.com they have hydraulic motors to match your flow with a 1 3/8" 6 spline PTO output. If I remember right they are about $250-280 depending on size. I have a 5' mower at home waiting for a few cold snowy days myself. Surplus Center was the best deal I could find for motors. You will also need two tees so you can tee a low pressure relief valve between the outbound hose and the inbound hose so when you shut the hydraulic power down your motor/mower can wind down. Otherwise they will blow up u-joints, shafts, seals, hoses or the motor itself. When you shut the flow down all at once the motor will become it's own pump from the blades spinning and something WILL give. John

  3. #3Knocker of rock2013-11-26 22:50

    Won't a motor control valve do that? A motor valve drains at neutral, while a loader valve is closed at neutral. Am I right? Kinda learning here

  4. #4partsandservice2013-11-29 21:01

    Knocker of rock, you are correct, but that would mean you have to replace the control section with a motor spool section. Relief valve will work. I prefer to install a check valve that is closed under pressure and open when not this creates a loop when the pressure is off and allows a freewheel slow down. No reverse but never needed that on a rotory cutter.

  5. #5Knocker of rock2013-11-29 23:55

    Or put a motor valve down stream of the existing valves if they have power beyond, or put a motor valve with power beyond upstream of the existing

  6. #6CRAFT2013-11-30 15:17

    What you NEED is commonly called "Cross Port Relief Valve" ….it's not just as easy as putting in a couple of "T's" …. LOL …..check it out ….

  7. #7gwhammy2013-12-05 07:39

    A one way pto drive for tractors that don't have live power will work also. That's what I put on one I had. This lets it free wheel when you shut the hydraulics off. Shuts down fast if you do it while cutting. I finally ruined the last brush hog I built and need to build another. On this one I'm going to make a three point hitch quick attachment with the hydraulic drive motor on it. The one I had worked really great, I had the front cut back so the blades hung out about six inches. You could take some decent trees down by notching into them. Probably not real safe but you could also reach fairly high and trim trees or set it on top and work your way down on them. I need to make another this winter also really miss not having one.