Performance, controlling power hop

Power hop is a condition where an MFWD-equipped tractor exhibits severe bounce and/or pitch motions at field working speeds when pulling a towed implement.  Each series of John Deere tractors exerts a different amount of weight on the front axle because of several factors. For example, 8030 Series Tractors will have more initial weight on the front axle because of design changes to several key features and it will require less weight than previous models to ballast it to a recommended 35% front split. Other series of tractors may require more or less weight. See a John Deere dealer to determine the correct amount of ballast for a particular tractor series.

 

Power hop can occur when pulling medium to high draft loads in loose, dry soil on top of a firm base and/or when climbing hills.  As a result, the tractor cannot maintain pull due to either loss of traction, rough ride, or both.  Make adjustments only after assuring that the guidelines for optimum performance with towed implements have been followed.  They are:

 

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

Then if power hop occurs:

 

  1. Increase front inflation pressures by 6 PSI and operate the tractor.

 

If power hop still occurs:

 

  1. Increase front inflation pressures by another 6 PSI and operate the tractor. Continue to increase the front inflation pressure as needed up to a maximum of 6 PSI above the maximum pressure rating for the tires (imprinted on the tire sidewall). Usually 6 to 12 PSI above the rated pressure for the front axle load will suffice to control power hop.

 

If power hop still occurs:

 

  1. Remove all front ballast weights.  Leave the same front maximum inflation pressure from the previous step and operate the tractor.

 

If power hop still occurs:

 

  1. Install 75% liquid fill in the front tires.  Reinflate the front tires to the maximum pressure rating for the tires and operate the tractor. See your John Deere dealer to determine exact amount of weight that will be added depending on the percent fill and tire size.

 

NOTE:  In most cases, step 4 will not be required to control power hop.

 
 
Last Updated : 24-Jul-2013