Valve Cover Gasket (Rocker Cover Gasket)

It is made of rubber or cork. Leaks are common on older engines. Spark plug well seals may be integrated. Over-tightening the cover bolts can distort the cover and cause leaks, so torque values matter. On many engines the cover includes the oil separator for crankcase ventilation. A leaking gasket is usually an inexpensive repair.

The gasket seals the joint between cover and head.

Leaking oil can drip onto the exhaust and smell or smoke. Oil in spark plug wells can cause misfires.