Quality of Cut Issues- Wash boarding from one cutting unit on a triple or five unit mower

Wash boarding from one cutting unit


 Wash boarding effect: 

  • This is the effect when one or all cutting units slow down so much that you can visibly see the ‘gather and shear’ action on the turf.
  • The above photo shows one cutting unit slowing down whilst the other two stay at the desired reel speed

Diagnosis-only to be carried out by a trained and capable person and after reading the manufacturers operators manual:

  1. Keep it simple.  Work out which cutting unit is the suspect. If capable swap this cutting unit to another position on the mower. (we are assuming that all units are of the same set up and sharpness)  Test mower and if wash boarding moves then it is a problem with the cutting unit.  Confirm this by moving the cutting unit back to its original position.  Check cutting unit for a sheared drive coupling or shaft, being severely off cut and general mechanical condition.
  2. If wash boarding stays then investigate the hydraulic or electric reel motor.  If hydraulic it could be       internal damage to the motor causing the oil to ‘be lazy’ and pass around the motor gears without turning them at full power.  It could also be the previous motor in the hydraulic circuit ‘leaking off’ back to the tank.  This can happen intermittently or continuously and can be tested by physically measuring the flow from the leak off with a jug and hydraulic blanker or fitting a pressure transducer with a data logger into the suspected motor leak off.  Sometimes the motor will only leak off back to tank when the next cutting unit in line is under load.