Contents Wiring diagrams Section: Diesel Engine All sections

How to Adjust the Timing Opel Astra G

Diesel Engine 13 illustrations ~1365 words

Remove

Remove air cleaner housing with air intake hose and hot film mass air flow meter – see illustration "Air Ducts".

Remove upper part of toothed belt cover – see operation "Toothed Belt Cover – Upper Part, Remove and Install".

For version with AC: Remove ribbed V-belts – see operation "Ribbed V-belts, Remove and Install".

Remove V-belt – see operation "V-belt, Remove and Install".

Remove lower part of toothed belt cover – see operation "Toothed Belt Cover – Lower Part, Remove and Install".

Check toothed belt tension, adjust if necessary – see operation "Toothed Belt Tension, Check".

Remove engine vent hose from camshaft housing cover.

Remove camshaft housing cover from camshaft housing.

Adjust

At fastening bolt (1) of toothed belt drive gear, turn crankshaft in engine rotational direction to approx. 90° (dimension I) before "1st cylinder TDC".

Inspect

1st cylinder exhaust cam (2) must point vertically upwards.

Install

Insert Dial gauge MKM-571-B (1) in Tool KM-661-1 (2) – arrow on KM-661-1 points towards engine timing side. Attach base (3) Ø 10 mm to dial gauge. To adjust dial gauge, left positioning pins of tool (I+II) must be seated in bores of camshaft housing. Set probe of dial gauge onto basic circle of 2nd cam (intake, 1st cylinder). Set dial gauge to "0" – ensure that the probe is not seated on the cam oil bore.

Caution

The Dial Gauge MKM-571 may be pre-tensioned by max. 0.5 mm, otherwise the resulting measurement will be incorrect.

Remove Tool KM-661-1 and set aside carefully – ensure that Dial Gauge MKM-571-B is not displaced.

Remove

Release injection pump pulley fastening bolts (3) and hand tighten – it must still be possible to turn injection pump pulley on injection pump flange.

Release fastening bolt (5) for toothed belt tension roller and turn adjusting eccentric (6) in direction of arrow (clockwise) until pointer (4) is positioned just before left stop.

Detach tooth belt (1) from camshaft pulley and injection pump pulley.

Remove fastening bolt (2) for camshaft pulley – counterhold with open-ended wrench at hexagon of camshaft. Install new fastening bolt for camshaft pulley and hand-tighten – camshaft pulley must still be able to rotate on camshaft – note installation position of washer.

Caution

Carefully position Tool KM-661-1 (2). The right positioning pins must be seated in the bores of the camshaft housing – ensure that Dial Gauge MKM-571-B (1) is not altered. Base (3) rests on inlet cam of the 1st cylinder.

Install

Install Holder KM-661-2 (3) over 4th cylinder.

Adjust

Rough adjustment: Carefully turn camshaft with open-ended spanner (1) at hex of camshaft in direction of arrow until elevation of approx. 0.80 mm (indicator on Gauge MKM-571-B) is attained.

Fine adjustment: Adjust elevation of 0.60 to 0.64 mm (indicator of Gauge MKM-571-B) with adjustment screw (2) at Holder KM-661-2.

Caution

Elevation of 0.60 to 0.64 mm is not a nominal value!

Adjust

With open-ended spanner turn injection pump flange until recess (1) on injection pump pulley aligns with injection pump flange recess and injection pump retaining bore (arrow).

Install

Mark out injection pump with Marker Pin KM-6011 (2).

Turn the crankshaft in the direction of engine rotation to just before "1st Cylinder TDC" using the fastening bolt for the toothed belt drive pulley.

Insert TDC Centring Pin KM-951 (3) into opening on transmission (arrow), and at the same time at fastening bolt of toothed belt drive gear, slowly further turn crankshaft in engine rotational direction until TDC centring pin engages in cylinder block or crankshaft webs to the stop.

Inspect

In this position, mark (1) on toothed belt drive gear must align with mark (2) on oil pump.

Install

Position tooth belt on camshaft pulley and injection pump pulley. Ensure that recess is positioned on the fuel injection pump gear is centrally positioned above the recess on the fuel injection pump flange.

Tension toothed belt:

Turn adjusting eccentric (1) in direction of arrow (anti-clockwise) until pointer is located just before right stop – tighten fastening bolt (2).

Tighten camshaft pulley on camshaft. The tightening torque of 75 Nm / 55 lbf. ft. + 60° + 5° must be observed as this has an impact on the camshaft elevation. Tighten fuel injection pump gear – tightening torque 25 Nm / 18 lbf. ft.

Remove

Remove Tool KM-661-1 and carefully set aside – ensure that Dial Gauge MKM-571-B is not altered. Remove Crankshaft Retaining Pin KM-951, Injection Pump Retaining Pin KM-6011 and Open-ended Wrench KM-661-2.

Adjust

Adjustment of new toothed belt:

At fastening bolt of toothed belt drive gear, turn crankshaft two turns (720°) in engine rotational direction to TDC – mark (1) on toothed belt drive gear must align with mark (2) on the oil pump.

Release fastening bolt (6) slightly and turn adjuster eccentric (5) in direction of arrow (clockwise) until pointer (3) on toothed belt tension roller aligns with the notch mark (4).

Tighten fastening bolt (6) of toothed belt tension roller – tightening torque 25 Nm / 18 lbf. ft.

Inspect

At fastening bolt of toothed belt drive gear, turn crankshaft two turns (720°) in engine rotational direction to TDC – mark (1) on toothed belt drive gear must align with mark (2) on the oil pump. Check adjustment of toothed belt tension roller. If the pointer (3) does not align with the notch mark (4), repeat the adjustment procedure.

Adjust

Run-in Toothed Belt, Adjust:

At fastening bolt of toothed belt drive gear, turn crankshaft two turns (720°) in engine rotational direction to TDC – mark (1) on toothed belt drive gear must align with mark (2) on the oil pump.

Release fastening bolt (6) slightly and turn adjuster eccentric (5) in direction of arrow (clockwise) until pointer (3) on toothed belt tension roller is approx. 4 mm/0.16 in to the left of the notch mark (4).

Tighten fastening bolt (6) of toothed belt tension roller – tightening torque 25 Nm / 18 lbf. ft.

Inspect

At fastening bolt of toothed belt drive gear, turn crankshaft two turns (720°) in engine rotational direction to TDC – mark (1) on toothed belt drive gear must align with mark (2) on the oil pump. Check adjustment of toothed belt tension roller. If the pointer (3) is not approx. 4 mm to the left of the notch marks (4), repeat the adjustment procedure.

Install

Move crankshaft two rotations (720°) in the direction of engine rotation just before "1st Cylinder TDC" using fastening bolt for toothed belt drive pulley.

Insert TDC Centring Pin KM-951 (3) into opening on transmission (arrow), and at the same time at fastening bolt of toothed belt drive gear, slowly further turn crankshaft in engine rotational direction until TDC centring pin engages in cylinder block or crankshaft webs to the stop.

Inspect

In this position, mark (1) on toothed belt drive gear must align with mark (2) on oil pump.

Adjust

With open-ended spanner turn injection pump flange until recess (1) on injection pump pulley aligns with injection pump flange recess and injection pump retaining bore (arrow).

Install

Mark out injection pump with Marker Pin KM-6011 (2).

Caution

Carefully position Tool KM-661-1 (2). The right positioning pins must be seated in the bores of the camshaft housing – ensure that Dial Gauge MKM-571-B (1) is not altered. Base (3) rests on inlet cam of the 1st cylinder.

Measure

Read off value on Dial Gauge MKM-571-B.

Nominal value: 0.55 mm ± 0.03 mm.

If the measured result does not match the nominal value, repeat adjustment.

Remove

Remove all retaining and adjusting tools.

Install

Install camshaft housing cover with new gasket to camshaft housing – tightening torque – 8 Nm / 6 lbf. ft.

Attach engine bleeding hose to camshaft housing cover.

Install lower part of toothed belt cover – see operation "Toothed Belt Cover – Lower Part, Remove and Install".

Install V-belt – see operation "V-belt, Remove and Install".

For version with AC: Install ribbed V-belt – see operation "Ribbed V-belt, Remove and Install".

Install upper part of toothed belt cover – see operation "Toothed Belt Cover – Upper Part, Remove and Install".

Install air cleaner housing with air intake hose and hot film mass air flow meter – see illustration "Air Ducts".