TM 5-4310-379-14
5-19.
Cylinder Head (Cont).
(12)
Remove exhaust valves (para. 5-18).
NOTE
Cylinder head should be steam cleaned before any testing is performed.
(13)
The cylinder head (17) should be inspected and checked for cracks before it can be reused. A cylinder head
which has cracks should not be reused. The cylinder head should be checked using the magnetic crack detector.
(14)
Perform pressure test on cylinder head (17) as follows:
WARNING
Do not perform pressure test of cylinder head that has cracks visible.
(a)
Close off water passages with steel plates and rubber gaskets and secure with bolts.
(b)
Install old or dummy fuel injectors in cylinder head (17) and secure with injector clamps and bolts. Torque
bolts to 20-25 Ib-ft (27-34 Nm).
(c)
Drill and tap one of the plates covering water passages for an air hose connection, and apply 40 psi (276
kPa) air pressure to water jacket.
(d)
Immerse the cylinder head in a tank of water heated to 180-200°F (82-93°C) for 20 minutes.
(e)
Leaks will be detected by air bubbles. Check for leaks at bottom and top of injector tubes, oil gallery,
cylinder head stud holes, exhaust ports, and top, bottom, and sides of cylinder head.
(f)
Remove air pressure.
(g)
Dry cylinder head completely.
(h)
Remove plates and gaskets.
(i)
Remove fuel injectors.
Change 1 5-66
