TM-9-2320-272-24-4

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL; VOLUME 4 OF 4

JUNE 1998

TM-9-2320-272-24-4 - Page 262 of 836

TM 9-2320-272-24-4

5-36. FUEL INJECTION PUMP MAINTENANCE (Contd)

h. Tappet and Spring Installation

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

CAUTION

When performing step 1, ensure flats on tappet align with recess

on the lower spring seat. Failure to do so may result in damage to

fuel pump housing.

NOTE

This task covers installation of two tappets for cylinders number

one and two. Remaining tappets are installed the same.

Install two tappets (1) in mating cylinders.

Install spring compressor clamp (3) on governor side of fuel pump housing (2) with two washers (4)

and screws (5).

Place spring compressor adapter (8) on shaft (7).

Position shaft (7) and adapter (8) on the first two tappets (1).

Position lever (6) on spring compressor clamp (3) and shaft (7).

Depress lever (6), compressing both tappets (1).

Turn knurled knob (12) on tappet holder (13) fully counterclockwise and apply GM grease to

ramp (11) and guide (10) on tappet holder (13).

While both tappets (1) are compressed, insert tappet holder (13) into side hole (9) of cylinders one

and two.

NOTE

Repeat steps 1 through 8 until all tappets and tappet holders are

installed.

Remove two screws (5), washers, (4), spring compressor clamp (3), lever (6), shaft (7), and

compressor adapter (8) from fuel pump housing (2).

Remove fuel pump housing (2) from vise.

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