Digga PDD-PD50, Service & Repair Manual

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PM-000100-D PDD - PD50 Service and Repair Manual - October 2017
BEFORE DISASSEMBLY
In the PDD-PD12 series, there is one single primary planetary gear set. In the PD15-PD22 series there is a primary and a secondary stack planetary
gear set using a common ring gear. In the PD25 – PD50 series there are primary and secondary individual gear sets.
UNIT DISASSEMBLY PROCEDURE
All parts should be inspected as they are removed from unit. Scribe or mark a line across the assembly mounting case, ring gear, and cover joints on
outside of gearbox to assure proper orientation of hood assembly, oil fill/ drain plug, motor mounting, etc., as the unit is reassembled.
1. Remove outer ring of bolts (refer to the relevant drive unit- diagram) from underside of gearbox assembly. Lift hood from gearbox assembly.
Remove drain plug and drain oil.
2. Remove inner ring of bolts and nyloc nuts (Refer to the relevant drive unit- diagram). Remove hydraulic motor from gearbox assembly. On PD8HF
and above remove 4 motor retaining bolts to remove motor then inner ring of input housing retaining bolts.
3. The primary planetary assembly is now ready for removal. Lift outer ring gear, sun gear and gear set from the output housing.
4. For secondary planet removal, remove bolts holding interim housing, remove housing, and lift outer ring gear, sun gear and gear set from the
output housing.
5. Most of the larger PD units will have a seal protector or carrier, remove this before moving to step #6.
6. On PDD – PD5, straighten locking tab which locates lock nut on the output shaft. On PD6 – PD50 remove key steel from keyway. Loosen lock
nut using the required tool and remove locknut and locking tab.
7. With output shaft down through a centre hole in hydraulic press table and unit supported by case, press shaft out by applying load to top end of
shaft (internal end) until it passes through inner shaft bearing. Outer shaft bearing will come out of unit attached to shaft.
The unit is now disassembled into groups of parts and/or subassemblies. The area requiring repair or service should be identified by thorough
inspection of the parts after they have been washed in solvent.
CAUTION:
ON PDD - PDX3 THE HOOD BOLTS ALSO HOLD THE GEARBOX TOGETHER. TAKE PRECAUTIONS WHEN
REMOVING THE HOOD THAT THE GEARBOX DOES NOT COME APART. FOR THESE DRIVE UNITS DISREGARD REMOVE INNER
RING OF BOLTS IN STEP 2. ON PD6 – PD7 THERE ARE 2 EXTRA BOLTS 180 DEGREES APART IN THE SAME CIRCLE OF BOLTS
WHICH HOLDS THE DRIVE UNITS HOOD ON, DO NOT REMOVE THESE BOLTS WHEN REMOVING HOOD , REFER TO PD6 – PD7
DRAWING PAGE 7.
CAUTION: RETAINING RING IS NO LONGER RETAINING OUTPUT SHAFT. TAKE PRECAUTIONS IF THE UNIT IS MOVED
BECAUSE THE SHAFT MAY FALL OUT.
CAUTION:
CARE SHOULD BE TAKEN NOT TO INJURE FEET OR DAMAGE OUTPUT SHAFT DURING THIS PROCEDURE.