3-31. REPAIR CYLINDER HEAD
a. Cylinder head air pressure test:
ST-1012 hydrostatic tester is used to check for coolant leaks in cylinder head.
Head is sealed with adapter plates then submerged in water tank. Air pressure is
applied to check for internal cracked passages and defective injector sleeves.
(1) Lay head on its side with intake manifold down.
(2) Place a fuel injector in each sleeve and secure with capscrews.
(3) Torque screws to 10 - 12 ft lbs (14 - 16 Nm).
(4) Pin upper arm of ST-1012 to lift eye cradle.
(5) Check that O-rings in ST-1013 lower adapter plate are installed and are in good condition. Replace O-rings
(6) Position lower adapter plate on head alining locator pin in plate with hole in head.