When placing the cylinder head
assembly on a bench, protect the cam
followers and injector spray tips, if the
injectors were not removed, by resting
the valve side of the head on 2-inch
Remove and discard the cylinder head
compression gaskets, oil seals, and water seals.
13. After the cylinder head has been removed, drain
the lubricating oil from the engine. Draining the oil at
this time will remove any coolant that may have
worked its way to the oil pan when the head was
Figure 2. Lifting or Installing Cylinder Head with Tool
Disassemble Cylinder Head
If complete disassembly of the cylinder head is necessary, refer to Valve Operating Mechanism and Exhaust
Valves for removal of the exhaust valve and injector operating mechanism.
After the cylinder head has been disassembled and all the plugs (except cup plugs) have been removed,
thoroughly steam clean the head. If the water passages are heavily coated with scale, remove the injector
tubes and water nozzles. Then clean the cylinder head in the same manner as outlined for cleaning the
cylinder block (Cylinder Block).
Clean all cylinder components with fuel oil and dry them with compressed air.
Inspect Cylinder Head
1. Before a cylinder head can be reused, it must be inspected for cracks. Five prescribed methods for
checking a cylinder head for cracks are as follows:
If any method reveals cracks, the cylinder head should be considered
unacceptable for reuse.
Magnetic Particle Method: The cylinder head is magnetized and then covered with a fine magnetic powder or
solution. Flaws, such as cracks, form a small local magnet which cause the magnetic particles in the powder or
solution to gather there, effectively marking the crack. The cylinder head must be demagnetized after the test.
Fluorescent Magnetic Particle Method: This method is similar to the magnetic particle method, but is more
sensitive since it employs magnetic particles which are fluorescent and glow under a black light. Very fine
cracks that may be missed using the first method, especially on discolored or dark surfaces, will be disclosed
under the black light.