TM 3-1040-263-34
Table 4-4. Troubleshooting--Continued
Item
No.
Malfunction
Probable cause
Corrective action
9
Low air flow-Continued
h. Scored cylinder, plunger, or piston
Replace faulty cylinder, plunger, or
assembly.
piston assembly (para 4-27 through
i. Incorrect head clearance ---------
Check head clearance(para 4-27
2
Popping or leaking second-
a. Incorrect positioning of heads
Check position of heads (fig. 4-9).
stage relief valve.
b. Foreign matter between intake
Clean
valve and seating surface.
c. Seized 3rd-stage plunger and cy-
Replace faulty third-stage plunger an d
linder,
cylinder (para 4-29).
d. Sticking 3rd-stage intake and dis-
Clean
charge valve.
e. 3rd-stage intake or discharge
Replace 3rd-stage valves and valve
valves defective.
plate (para 4-29).
f. 3rd-stage intake or discharge
Replace distorted 3rd-stage valve or
valves or sprints distorted.
spring (para 4-29).
g. Clogged 3rd-stage heat exchanger
Clean or replace faulty component
or aftercooler.
3
Low oil pressure .---------
a. Loose connections on oil supply
Tighten connections
tube.
b. Low oil level in oil sump.
Fill oil sump (TM 3-1040-26 -12)
c. Clogged oil strainer -----------
Clean screen of oil strainer (TM 3-
1040-263--12).
d. Excessively worn keystone or
Measure clearances and replace worn
crankshaft journal.
components (para 4-33 and 4-34).
e. Faulty oil pump-------------
Replace oil pump (para 4--19)
4
High oil pressure----
a. Faulty oil pump - ----------
Replace oil pump (para 4 --19 and 4-21)
5
Oil Leakage---------
a. Oil pump seal damaged -------
Replace oil pump (para 4-19 and 4-21)
b. High blowby or through pump-------
Refer to items 6 and 7 below
c. Leaky preformed packing --------
Place preformed packing (para 4-19
d. Loose connections or fittings
Tighten all connections and fittings
e. Drain plug
Replace drain plug (para 4-23b)
6
High blowby
a. Compression rings worn, scored
Check and, if necessary, replace rings
cracked, or incorrectly
properly (para 4-27b).
Assembled.
b. Plunger or cylinder worn or
Replace worn or scored component
scored.
(para 4-28b and 4-29b).
c. Piston assembly or cylinder worn
Replace worn or scored component
or scored.
NOTE
High oil through put occurs
when there is excessive oil
flow between the keystone
and crankshaft journal-as
detected by oil leakage from
blowby port.
7
High oil through put
a.
Excessive keystone or crankshaft
Determine worn component, and replace
journal clearance.
as required (para 4-33 and 4-34).
b.
High oil pressure
Refer to item 4 above
8
Pumping oil through compres-
a.
Poor fit of 1st-stage piston
Replace 1st-stage piston or cylinder
sor
assembly and cylinder.
b.
Poor fit of 2nd-stage plunger and
Replace 2nd stage plunger or cylinder
cylinder.
c.
Damaged or worn rings
Replace rings (para 4-27b)
4-30
