CYLINDER HEAD

1. Cylinder Head Malfunctions

A cracked cylinder head will produce the same results as a cracked engine block, and the same holds true for clogged oil passages in the cylinder head. A common problem in cylinder heads is a "blown" head gasket. This is usually indicated by two adjacent (side-by-side) cylinders failing to deliver power (misfiring).

Flow of air due to blown cylinder head gasket

Carbon build-up is another problem encountered with heads. The carbon tends to hold heat which ignites the fuel prematurely. When preignition is experienced in the engine and it cannot be remedied through the electrical system, the head is usually at fault.

2. Cylinder Head Troubleshooting and Remedies

If the two adjacent cylinders are misfiring, perform a compression test to verify the problem before removing the cylinder head (it could be faulty ignition). When a head gasket "blows," the break is usually between two adjacent cylinders, and air, instead of being compressed, simply moves back and forth between the cylinders. A compression test would indicate little or no compression in either of these two cylinders. To remedy this problem, the head gasket must be replaced. The cylinder head and block must be checked to ensure the surface has not warped. A perfectly flat surface is required to ensure an air-tight seal. If an uneven surface is detected on either the cylinder head or the cylinder block, it must be machined flat (commonly termed shaving or grinding the head or block). If preignition exists, and after troubleshooting the electrical system, it is determined that the

cylinder head is the cause, remedy the malfunction by removing the head and cleaning out all

carbon deposits.