Positive Crankcase Ventilation: Testing and Inspection

Fig. 64 FLAME GUARD AND P.C.V. NIPPLE:

Check hoses, nipple and flame guard (where applicable) for condition and clogging. This can be performed by visual inspection of each individual component. Fig. 64.

Fig. 105 BLOCKED P.C.V. SYSTEM (NON TURBO ONLY):

(except turbo)
A blocked flame trap will cause the crankcase ventilation system to malfunction and result in high crankcase pressure. Fig. 105.

Symptoms are:
- oil dipstick "jumps out" of the pipe
- oil leakage at the seals in the cylinder block
- seals must not always be replaced if they are leaking due to a blocked flame trap. Fix the flame trap, clean the engine and check if seals are still leaking or not.
- the engine knocking (change to a new flame trap if necessary, see "COMPONENT REPLACEMENT AND REPAIR PROCEDURES")

Reasons for a blocked flame trap may be:
-too long intervals between engine oil changes
-the engine oil used is of poor quality

Fig. 144 CRANKCASE VENTILATION HOSE (TURBO ONLY):

(turbo only)
Crankcase ventilation hose:
An incorrectly installed crankcase ventilation hose can result in starting problems (the air flow sensor plate does not lift).
If the crankcase ventilation hose kinks, a positive pressure is formed in the crankcase. This blocks the oil return from the turbo-charger which in turn causes oil to leak onto the turbo-charger shaft seals.
It is therefore important to check that the hose is not kinked at the nipple on the oil trap, next to the cold start injector, or between the fuel line and the line elbow.

To fix kinked hose:
1. Cut the insulating hose to half the diameter of the hose at an angle of 45°. Fig. 144.
2. Press the crankcase ventilation hose up to the bead in the pipe. Install the insulating hose on the crankcase ventilation hose so that it fits tightly against the pipe.
3. Pull the crankcase ventilation hose over the cold start injector.