ENGINE DOES NOT DEVELOP FULL POWER. (Cont) -726250143

TM 9-2320-364-34-1

Allow engine to cool before performing troubleshooting maintenance. If necessary use insulated pads

and gloves. Hot engine components will burn and cause injury to personnel.

COMPRESSION TEST

(1) Start engine, (TM 9-2320-364-10).

(2) Remove radiator cap and check for

exhaust gas bubbles in coolant.

(a) If bubbles are present in coolant,

turn OFF ENGINE switch and go

to Step (3) below.

(b) If there are no bubbles, turn OFF

ENGINE switch and go to Step (6)

below.

(3) Perform compression test on each

cylinder, (Para 3-3).

(a) If pressure is below minimum

requirements listed in Table 2-6,

go to Step (4) below.

(b) If pressure is above minimum

requirements listed in Table 2-6,

fault not corrected. Notify

supervisor.

(4) Remove cylinder head, (Para 3-7).

(5) Check cylinder head for cracks,

leaking valve seats or injector tubes.

(a) If any of the components listed

above are damaged, replace the

cylinder head, (Para 3-7).

(b) If all of the components listed

above are OK, go to Step (6)

below.

(6) Remove 14 screws and six air box

covers and gaskets. Discard

gaskets.

(7) Check pistons and piston rings for

damage. Rings should spring in

and out when pushed in.

(a) If pistons and/or piston rings are

damaged, replace engine,

(Para 3-4).

(b) If pistons and piston rings

are not damaged, pistons and

piston rings are OK, fault not

corrected. Notify supervisor.

(8) Install cylinder head.

Table 2-6. Compression Pressure Specifications

Minimum Compression

Altitude above Sea Level

Pressure at 600 RPM

psi

kPa

feet

meters

450

3101

500

152

415

2859

2,500

762

385

2653

5,000

1,524

355

2446

7,500

2,286

330

2274

10,000

3,048

2-61