Oil Pump Drive Shaft: Service and Repair

1st version





104 Intermediate gear shaft
120 O-ring
121 Cap
122 Screw plug M26 x 1.5
123 Retaining bolt M8
124 Thrust piece
125 Bearing bushing
126 Helical gear shaft
127 Bearing bushing
128 Oil pump shaft


2nd version





104 Intermediate gear shaft
120 O-ring
122 Screw plug M 22 x 1.5
123 Retaining bolt M 10
124 Thrust piece
125 Bearing bushing
126 Helical gear shaft
127 Bearing bushing
128 Oil pump shaft


3rd version





104 Intermediate gear shaft
120 O-ring
122 Screw plug M 22 x 1.5
123 Retaining bolt M 10
124 Thrust piece
125 Bearing bushing
126 Helical gear shaft
126a Thrust ring
127 Bearing bushing
128 Oil pump shaft


Removal and Installation of Helical Gear Shaft

Removal
1 Remove screw plug (122).
2 On the 1st version, remove cap (121) and 0-ring (120).
3 Remove retaining bolt (123).
4 Withdraw thrust piece (124). If this resists removal, turn screw plug (122) in slightly, position pliers on screw plug and then withdraw thrust piece.
5 Withdraw helical gear shaft (126) using pointed pliers.
6 Withdraw bearing bushing (127), again using pointed pliers.
7 Entire thrust piece (124) will need replacing if end face of bearing bushing (125) in thrust piece is worn; this will also apply to helical gear (126) if its thrust collar shows signs of wear.
8 Check O-ring for porous places and damage, replacing if necessary.

Installation
9 Insert bearing bushing (127).
10 Insert helical gear shaft (126).
11 Insert thrust piece (124).


CAUTION: Carefully put on thrust pieces of the 2nd and 3rd version to avoid damage to O-ring (120).


12 Insert and tighten retaining bolts (123) (reference values 25 Nm and 45 Nm, respectively).
13 On 1st version, fit O-ring and cap.
14 Insert screw plug and torque to 50 Nm (5 Kpm).