Testing Yanmar PFR Fuel Injection Pumps

PREPARATION

Using the chart below:
  1. Ensure the total rack travel is correct and that the control rack moves smoothly thru the full length of it's travel.
  2. When mounting pump to cambox for testing, use the applicable plate for pump type and number of cylinders.

      Pump Type Rack Travel Mounting Plate
      PFR-K1 18 mm 121120-51110
      PFR-K2 18 mm 121120-51120
      PFR-K3 18 mm 121120-51130
      PFR0707-1 18 mm 121120-51160
      PFR0707-2 18 mm 121120-51170
      PFR0707-3 18 mm 121120-51180
      PFR0707-M2 15 mm 121120-51270
      PFR0707-M3 15 mm 121120-51280

Injection Timing Adjustment
  1. Remove delivery valve holder and delivery valve.
  2. Rotate camshaft and set plunger at top dead center (7 mm).
  3. With a dial indicator, and Yanmar special tool 158090-51300, measure
    distance between top surface of barrel and top of plunger.
  4. If top clearance is not within specification adjust by adding or removing
    shims under the plunger spring seat.

Delivery Valve Leakage Test
  1. Attach a 1000 kgf/cm2 gauge to delivery valve holder.
    (Yanmar special tool part number 121820-92540)
  2. Operate pump at 200 RPM until pressure on gauge reads 100 kgf/cm2.
  3. Measure time interval for pressure to drop from 100 kfg/cm2 to 90 kgf/cm2.
  4. If interval is less than 5 seconds, clean or replace delivery valve and re-test.

Testing Plunger Pressure
  1. Attach a 1000 kgf/cm2 gauge to delivery valve holder.
  2. Raise pressure to 500 kgf/cm2 and ensure no sudden pressure drop or external leakage occurs.

Fuel Output Test
  1. Align mark on rack with the reference surface and lock rack.
  2. Operate pump at rated speed per calibration specification.
  3. Adjust as necessary to obtain specified delivery in non-adjustable cylinder and relock rack. If mark on rack does not align with the reference edge you will need to remark the rack at the end of the test.

Balancing Fuel Delivery on Remaining Cylinders

Adjust cylinders #2 and #3 to match cylinder #1

  YPFR-K Type Pump
  1. Loosen pinion locking screw.
  2. Rotate control sleeve (Left decreases fuel, Right increases fuel).
  3. Tighten pinion locking screw.
  4. Confirm output on test stand.

  YPFR0707 and YPFR0707-M Type Pumps
  1. Loosen delivery valve holder.
  2. Loosen adjusting plate locking screw.
  3. Turn adjusting screw and observe movement of barrel stopper
    (Left decreases fuel, Right increases fuel).
  4. Tighten adjusting plate locking fuel and retorque delivery valve holder.
  5. Confirm output on test stand.