Ford Sierra Quiz
Routine maintenance and servicing

Crankcase ventilation system check (Every 12 000 miles (20 000 km) or 12 months)

In this manual: Routine maintenance and servicing
Ford Sierra Service and Repair Manual — 1Routine maintenance and servicing — 26SOHC engines — 76Cooling, heating and air conditioning systems — 14Fuel and exhaust systems - carburettor — 18Fuel and exhaust systems - fuel injection — 18Engine electrical systems — 20Braking system — 27Suspension and steering — 28Bodywork and fittings — 36Body electrical system — 29Wiring diagrams — 1Reference — 1
~1min read

1 Inspect the crankcase ventilation system for blockage or damage. A blocked hose can cause a build-up of crankcase pressure, which in turn can cause oil leaks (see illustration).

35.1 Loosening the crankcase ventilation hose clip - CVH models
35.1 Loosening the crankcase ventilation hose clip - CVH models

2 On carburettor model SOHC engines, clean the oil filler cap with paraffin and check that the vent valve is not blocked by pulling it from the oil separator and loosening the hose clip (Section 42).

3 On CVH engines, check that the oil separator and mushroom valve are not blocked, and clean if necessary (see illustration).

35.3 Oil separator (1) and mushroom valve (2) locations in air cleaner - CVH
35.3 Oil separator (1) and mushroom valve (2) locations in air cleaner - CVH models

Test yourself

A quick Ford Sierra quiz: every answer comes with an explanation and a link to the manual page.