Balance Shaft Belt: Adjustments

CHECKING BALANCE BELT TENSION

In order to perform this operation, Porsche special tool P9201 is needed, Tools and Equipment

Note: Only check and adjust drive belt tightness on a cold engine (ambient temperature approx. 20° C/68° F).

1. Unbolt and remove engine underguard.

2. Remove Poly-rib belt.





Note: Always first loosen hex bolts of linkage slightly before unscrewing locknuts.





3. Unscrew vent hose and take off drive belt cover.





4. Slacken pulley so that it no longer tensions drive belt.





5a. Turn crankshaft clockwise until TDC mark on camshaft sprocket is aligned with cast mark in mount of distributor cap.





b. TDC mark on flywheel and cast clutch housing must also be aligned.

Balance Shaft Timing Marks:

6. Check basic position of balance-shaft sprockets. Marks on sprockets must be aligned with marks on rear drive-belt cover.

7. Prepare Special Tool P 9201 for testing. Pull lockpin from Special Tool and push out gauge pin opposite the lockpin completely. Zero telltale needle.





8. Slide Special Tool on to belt. Press measuring key (arrowed) in slowly until lockpin is heard to engage and read the value from dial gauge.

Note: Always zero telltale needle on gauge after lockpin has engaged (turned anticlockwise) to exclude wrong gauge readings.

Specified value (new or used belt): 2.7 +/- 0.3 scale gradations. If necessary, correct belt tension.

ADJUSTING





9. Turn tensioning roller clockwise to increase tension. Turn anti-clockwise to loosen. Tighten hex nut to 45 Nm (33 ft lb).

Balance Shaft Belt:

10. After adjusting drive-belt tension, adjust idler pulley. Using Special Tool 9207 or 0.5 mm (0.020 in) feeler gauge so there is a clearance of 0.5 mm between drive belt and pulley when upper portion of drive is preloaded 0 to 1 mm. Tighten pulley in this position. If correct clearance cannot be reached, turn pulley through 180° and repeat adjustment. Tighten hex nut to 45 Nm (33 ft lb).

11. Install Poly-rib belt, servo pump belt and adjust.

Note: Slides must make full-surface with contact belt. While measuring, do not allow the Special Tool to turn or move on the belt.