Timing Chain Guide: Service and Repair

Removing and Installing Slide Rails

NOTE:
All slide rails in cylinder heads of engines 116 are identical.
Likewise, the slide rails in cylinder heads of all engines 117 are identical.
On the other hand, the length of the pertinent bearing pins of light alloy engines differ from those of cast-iron engines.

Guide Rails in Inside and Outside left of Cylinder Head:





1 Position piston of cylinder 1 to ignition TDC.
2 Remove distributor.
3 Take out power steering pump with bracket
4 Use impact extractor to knock out bearing pin and take out guide rail .

NOTE: When performing repairs, the guide fails in the cylinder heads of engines 116 should be reamed open and replaced at the mounting holes: Round hole specified dia 8.25 mm, oval hole specified dia. 8.20 mm. Guide rails with these enlarged mounting holes have been fitted as standard since April 1987.

5 When installing, pay attention to position of guide rail. install oval hole facing down. The bearing pins differ from those of the cast iron engines.

Guide Rail Position, Engine 116:

Bearing pins
Light alloy engines L = 46 mm
Cast iron engines L = 56 mm

Guide Rail Position, Engine 117:

Bearing pins
Light alloy engines L = 48 mm
Cast iron engines L = 56 mm


Slide Rails in Cylinder Head Right:





1 Remove alternator together with mounting bracket.





2 Knock out bearing pin with impact puller and remove slide rail.

Slide Rails in Crankcase





1 Remove timing case cover. Service and Repair
2 Unscrew slide rail (87 or 79).





Engine 116.96, 117.96 (left side of image)
1 Slide rail
2 Bolt M8 x 40
a 43.8 mm

Engine 116.98 (right side of image)
3 Slide rail
4 Bolt M8 x 38
b 55 mm

The two slide rails in the crankcase differ from those of cast-iron engines.






1,2 Engine 116.96 and 117.96
3,4 Cast-iron engine 116.98 and 117.98
a 114 mm
b 26 mm

The straight slide rail (1) in the crankcase is asymmetrical (arrow) and slides onto the pins (2) screwed into the crankcase.


Tension Arm for Oil Pump Chain





1 Remove timing case cover. Service and Repair
2 Remove lock and remove tension arm (84).