Cylinder Head Assembly: Service Precautions

CAUTION: A removed engine with installed Hydraulic Valve Compensation (HVA) elements must not be left upside down for longer than 10 minutes, as otherwise HVA elements will lose hydraulic fluid and no longer function correctly.

Always store HVA elements upright to prevent oil from running out.

CAUTION: Attention must be paid to the following if work had been carried out on the cylinder head, for which the camshaft was removed. Hydraulic valve tappets expand when without load from the camshaft and must be allowed enough time after installation to constrict again. Consequently fast assembly could cause "closed" valves to still be open and have contact with the pistons.

The following waiting times must be allowed between installation of the camshaft and mounting of the cylinder head:

Ambient Temperature: Time:
20°C (68°F) 4 minutes
10 to 20°C (50-68°F) 11 minutes
0 to 10°C (32-50°F) 30 minutes.

After installation of the camshaft and timing chain, the engine may first be cranked after the following wait times:

Ambient Temperature: Time:
20°C (68°F) 10 minutes
10 to 20°C (50-68°F) 30 minutes
0 to 10°C (32-50°F) 75 minutes

Working on Valve Train with Mounted Cylinder Head
- Turn crankshaft in engine's direction of rotation to approx. 30° from the TDC mark, so that in this manner no pistons are in TDC.
- Install camshaft so that the cam peaks of cylinder no. 1 overlap.
- Conform with the above mentioned waiting times.
- Turn crankshaft back to TDC position and mount timing chain.
- Crank engine not earlier than 10 minutes after installation of the camshaft.
- If necessary, drain engine oil and fill engine with new engine oil after completion of engine assembly. Check oil level after installation and road test.

CAUTION: HVA elements must not rattle during a trial run of the engine after finishing repairs. If necessary, the engine must be run at speeds below 2,000 rpm until this rattling stops.