11 12 729 Checking cylinder head for watertightness (M52TU / M54 / M56)
Special tools required:
- 11 7 390
- 11 7 391
- 11 7 392
- 11 7 393
- 11 7 394
- 11 7 395
- 11 7 396
- 11 7 397
- 11 7 398
(cylinder head dismantled
Prepare special tool kit 11 7 390.
NOTE:
Special tool kit in 390 consists of special tools 11 7 391 / 11 7 392 / 11 7 393 / 11 7 394 / 11 7 395 / 11 7 396 / 11 7 397 / 11 7 398.
Place special tools 11 7 391 / 11 7 392 on cylinder head sealing surface and screw down with cylinder head bolts.
Turn back screw (1).
NOTE:
special tool 11 7 394 is secured with a pin (2).
Fit special tool 11 7394.
Insert screw (1) by hand until special tool 11 7 393 rests on sealing surface.
Tighten down screw (1) by approx. a half to one turn.
Check sealing rings (1) and coat with water as anti -friction coating. Insert special tool 11 7 395 and tighten down.
Seal coolant apertures with special tool kit 11 7 390.
Connect compressed air to special tool 11 7 395.
Immerse cylinder head in a water bath. Inspection pressure 4.5 bar.
Check cylinder head for escaping air (cracks).
NOTE:
If necessary, soften the bath water with a cleaning agent.