(7) Air in fuel system.
(8) Unsatisfactory injectors.
(9) Improper governor adjustment.
(10) Loss of compression.
f. Will not shut off.
(1) Gradual development of the condition in normal operation is usually caused by
misalinement of external control linkage. When a stop is attempted, the engine continues to run
somewhat below idle.
(2) Diluted oil in air boxes and hot engine.
g. Engine knocks (detonates).
(1) Because of the diesel's high compression, its characteristic sound is sometimes mistaken
for knocking. To detect true knocking, place a screwdriver or bar against the engine with the other end
to the ear, and listen to engine sounds at various positions. Hammering in a diesel can be caused by
either fuel or mechanical knocks. If a hard metallic knock indicates detonation in one or more cylinders,
the engine should be immediately stopped to prevent serious damage from the excessive pressures
accompanying detonation. Detonation is caused by the presence of fuel oil or lubricating oil in the air
charge of the cylinders during the compression stroke. The engine should be checked for:
(a) Leaky injectors.
(b) Leaking fuel connections in cylinder head.
(d) Leaky blower housing gasket.
(e) Leaky blower oil seals.
(f) Control rack improperly adjusted.
(g) Hydraulic valve lash adjusters sticking.