- Remove the central screw and the belleville
washer
- Remove the chain with the crown gear.
- Remove the crankshaft control pinion.
- Remove the oil pump by undoing the 2 screws
indicated in the figure.
- Remove the oil pump seal.
IT IS ADVISABLE TO MARK THE CHAIN IN ORDER TO EN-
SURE THAT THE INITIAL DIRECTION OF ROTATION IS
MAINTAINED.
Inspection
- Remove the two screws and the oil pump cover.
- Remove the clip retaining the innermost rotor.
- Remove and wash the rotors thoroughly with a
degreasing solvent and compressed air.
- Reassemble the rotors in the pump body, keep-
ing the two reference marks visible Replace the
clip.
- Measure distance between rotors (inner rotor/
outer rotor) with a thickness gauge in the position
shown in the picture.
Characteristic
Admissible maximum clearance 1
0.15 mm
Measure the distance between the outer rotor and
the pump body (see figure).
Characteristic
Admissible maximum clearance 2
0.20 mm
MSS ZIP 100 4T Engine
ENG - 113