Hydraulic chipper conversion

   / Hydraulic chipper conversion #1  


Platinum Member
May 4, 2010
Jessup Mill, NC
Rk55HC 4n1 fel/bh, Power-Trac 1850, 425d, Terex pt30, Kubota kx033, bx1880, yanmar 8x8 dumper, Magnatrac mh5000 w/ loader, six way blade & backhoe, Dew-eze ATM72LC Slope Mower, Terramite t6 4wd, DR Power brush mower
I have a Dr chipper that had an 18hp engine driving a centrifugal clutch with two v-belts turning the chipper wheel.

Engine is dead and I've got a bunch of machines with similar hp available to hydraulic pto.

I've sized a motor to deliver the rpm&hp to the system, my question is, can I eliminate the clutch/belts and direct drive the wheel. If so, what protection do I need, other than the system relief, to run the chipper and not cause damage in the event of sudden stop?

The main advantage of eliminating the belts is reduced size (footprint) of the chipper... And no belts to replace.

Alternatively, if direct driving the wheel is a bad idea can I direct drive the clutch and use shorter belts to reduce the amount of space?
Thanks for your thoughts, I searched and didn't find similar posts... If I missed an existing answer please just point me to it.
   / Hydraulic chipper conversion #2  
I think direct drive would work fine. A hydraulic motor has very little inertia so could stop suddenly without hurting anything.
   / Hydraulic chipper conversion #3  
I'd at least drive it through a flex coupler in case there's a slight misalignment between chipper and motor shafts. The chipper flywheel is large and takes a lot of torque to get started. The hydraulic motor should have better starting torque than the original gas engine (depending on the type of hydrauic motor) but the gas engine drove through a clutch. With the direct drive I'd want a hydraulic motor that had more starting torque than the gas engine's torque at it's operating speed (usually 3600 rpm). How much more? I'm not sure.... depends on how long the clutch slips on startup.

Safest thing for ensuring that it works would be to keep the clutch and belts. That'd also protect against sudden stops of the rotor but I suspect that a relief valve would be enough.