Valve cover leaks are one of the most common oil leaks. On many modern engines the valve cover also contains the PCV valve or oil separator, so the cover itself can be the problem.
Common Causes
- Hardened or shrunken valve cover gaskets.
- Cracked or warped plastic covers.
- A clogged PCV system raising crankcase pressure.
- Over-tightened bolts distorting the cover.
Symptoms
- Oil running down the back or sides of the head.
- Oil in the spark plug wells.
- Burning oil smell from the exhaust manifold.
- Whistling or rough idle from a failed integrated PCV diaphragm.
Repair Tips
- Replace the gasket, spark plug tube seals and grommets together.
- Replace the cover if it is cracked or the integrated PCV has failed.
- Tighten bolts in sequence to the low torque specified.
Evergreen Parts
Evergreen offers cylinder heads and components identified by engine or vehicle application. Use the Evergreen eCatalog to find the right part, and see where to buy Evergreen through our authorized distributors.
