Timing chain tensioner piston replace

# Timing chain tensioner piston, remove and install

Remove the timing chain tensioner plug from the right side of the cylinder head |
CAUTION: Plug is under considerable spring tension !
Access to the tensioner plug can be made easier by removing the washer fluid bottle, and if necessary, dismounting the air conditioning compressor.
Remove spring and piston.

### Installation:

Image shows order of parts installation. |
Check length of spring, nominal value is 159mm ± 0.5 (6.260" ± 0.020") |
Narrow end of spring faces out to the plug. |
Piston and cylinder are a matched set, and should be replaced as a pair. |
Install sleeve, if removed, with new seal and tighten to 50 Nm (36 ft lbs.) |
Install piston with groove on slotted end facing up, and groove on other end facing the exhaust manifold. |
Tighten piston to 40 Nm (29 ft lbs. ) |
If old style tensioner plug is installed, unscrew nipple on end of plug, replace O ring. Add engine oil through nipple until oil runs out of plug. Tighten nipple. Newer style plugs don't have the nipple. With newer style plugs, simply start engine and run at 2-3000 rpm for several minutes to pump up tensioner piston.

E30 M3 Repair Manual V2.7. Copyright ©1999-2001 Koala Motorsport & Brett Anderson