Controlling Power Hop—MFWD Tractors

Power hop causes tractor bouncing and/or jumping at field working speeds under 16 km/h (10 mph). It can occur when the tractor is pulling towed implements at medium to high draft loads in loose, dry soil on top of a firm base and/or when climbing hills.

Make adjustments ONLY after making sure the following performance guidelines have been followed.

• No more than 35% of the tractor weight on the front axle
• If liquid ballast is used in rear tires, it should not exceed 40% (4 o'clock valve stem position)
• Front and rear inflation pressures set correctly based on static loads. See section 80 Wheels, Tires, and Treads.

Then if Power Hop Occurs:

1. Increase front inflation pressures by 40 kPa (0.4 bar; 6 psi).

   If Power Hop Still Occurs:

2. Increase front inflation pressures by another 40 kPa (0.4 bar; 6 psi) and operate tractor.
3. Continue to increase front inflation pressures in 10 kPa (0.1 bar; 2 psi) increments up to a maximum of 40 kPa (0.4 bar; 6 psi) ABOVE maximum pressure rating for the tires (imprinted on tire sidewall).

   IMPORTANT: Front tire pressure should not exceed 40 kPa (0.4 bar; 6 psi) more than the maximum rated inflation pressure shown on tire side wall.

   If Power Hop Still Occurs:

4. Install up to 75% liquid fill in the front tires and remove an equivalent amount of front cast weight to maintain recommended weight split. Re-inflate the front tires to the maximum pressure rating for the tires and operate the tractor. See Using Liquid Ballast in this section to determine exact amount of weight that will be added. NOTE: In most cases step 4 will not be required to control power hop.