Volkswagen Workshop Service and Repair Manuals

(Adjusting valve timing)

Special tools, testers and auxiliary items

• ◆ V.A.G 1331 Torque wrench (5...50 Nm)

Removing

• ‒ Remove ribbed belt .
• ‒ Remove vibration damper and toothed belt guard upper and lower parts.
• ‒ Mark D.O.R. of toothed belt.
• ‒ Loosen coolant pump/tensioning roller and remove toothed belt.

Installing

Prerequisites

• ● Engine cold
• ● Pistons not positioned at TDC

Work sequence

Engine codes ABD, ABU

Engine code AEA, AEE, AEX, APQ => Page 13-24

• ‒ Place toothed belt on crankshaft sprocket. For used belts note direction of rotation.
• ‒ Install toothed belt guard lower part.

Note:

If a piston is at TDC the valves could strike the piston when turning the camshaft.

• ‒ → Set camshaft sprocket to mark -arrow A-.
• ‒ Install belt pulley (note fixing arrangement).
• ‒ Set crankshaft to TDC No. 1 cylinder. Notch on the belt pulley must align with "0" mark on lower part of toothed belt guard -arrow B-.
• ‒ Fit toothed belt on camshaft and coolant pump sprockets.

• ‒ → Tension toothed belt by turning coolant pump.

• ‒ → Check toothed belt tension. At the point indicated it must just be possible to turn the toothed belt through 90 ° with the thumb and forefinger.
• ‒ Tighten coolant pump securing bolts to
       10 Nm.
• ‒ Rotate crankshaft two full turns and check adjustment.
• ‒ Install toothed belt guard upper part.
• ‒ Install ribbed belt => Page 13-19 .
• ‒ Install ribbed belt cover.
• ‒ Check ignition timing, adjust if necessary:

=> Repair group 28; Injection and ignition system; Checking and adjusting ignition timing.

Engine code AEA, AEE, AEX, APQ

Note:

If a piston is at TDC the valves could strike the piston when turning the camshaft.

• ‒ → Set camshaft sprocket to mark -arrow A-.
• ‒ Set crankshaft to TDC No. 1 cylinder. The ground or offset tooth on the crankshaft toothed belt pulley must align with the marking on the seal flange -arrow B-.
• ‒ Fit toothed belt. For used belts note direction of rotation.

• ‒ → Install tensioning roller and tighten securing nut hand-tight. The slot in the base plate -1- must engage over securing bolt -2- .
• ‒ Tension toothed belt by turning the tensioning roller in direction of arrow until the indicator -3- aligns with the groove in the base plate -arrow-.
• ‒ Tighten clamping nut on tensioning roller.
       Tightening torque: 20 Nm
• ‒ Turn crankshaft two complete turns in engine direction of rotation, set again to to TDC and check adjustment.
• ‒ Install toothed belt guard upper and lower parts.
• ‒ Install belt pulley (note fixing arrangement).
• ‒ Install ribbed belt => Page 13-19 .
• ‒ Install ribbed belt cover.
• ‒ Check ignition timing, adjust if necessary:

=> Repair group 28; Injection and ignition system; Checking and adjusting ignition timing.