Removal and installation, checking of the chain tensioner (BMW 3 Series E30)

Engine M10, M30 (models 316 and 316) produced before August 1988, 318i produced before August 1987, 323i and 325i)

If the chain is making a loud noise, which indicates that the tensioner is not working correctly, remove and check the chain tensioner.

The chain tensioner is mounted on the right side of the engine crankcase. It tensions the timing chain by means of the tension spring force and also by means of the oil pressure in the tensioner, which depends on the oil content in the engine.

Unusual noises when the chain is running may have the following causes:

• Air is not removed from the piston properly.
• The piston is worn out.
• The air outlet slot is clogged.
• The ball valve in the piston does not work.
• Spring tension is too high or too low.

Removal

Unscrew the locking bolt "E".

Caution: The bolt is under high tension spring force.

Remove the tension spring and piston from the tensioner. Check

Measure the length of the tension spring in a free state. Specified value: 155.5 mm.



Shake piston "K" while checking the free movement of ball "H".



Check the valve operation. To do this, blow into the piston from side 1 (the valve must be open). Then blow into the piston from side 2 (now the valve should close).

If this does not happen, remove valve "F" from sleeve "G" and clean it. In this case, the air outlet slot "I" should not be clogged.

Installation

Insert the piston with the spring and a new gasket and tighten the locking bolt slightly, just a few turns. Note: The conical part of the spring must face the locking bolt.

Unscrew the cylinder head cover and camshaft sprocket.



Move tension bar "1" in both directions until oil comes out through the lock bolt until noticeable resistance appears.

Tighten the locking bolt to a torque of 35 Nm.

Tighten the cylinder head cover and camshaft sprocket (see section "Removal and installation the cylinder head").

Original publication posted on the website: bmwman.ru