TM-9-2350-311-10

HOWITZER, MEDIUM, SELF-PROPELLED, 155MM; M109A2, M109A3, M109A4 AND M109A5

TECHNICAL MANUAL; OPERATOR’S MANUAL

NOVEMBER 1994

TM-9-2350-311-10 - Page 181 of 775

TM 9-2350-311-10

Item

No.

73.1

lnterval

Monthly

Table 2-1. PREVENTIVE MAINTENANCE CHECKS AND SERVICES

FOR M109 SELF-PROPELLED HOWITZER

Location

Item to Check/

Service

Muzzle Brake and

Bore Evacuator

Assembly Thrust

Collar Setscrews

Crewmember

Procedure

CHIEF OF SECTION

Inspect setscrew (1) holding the ball and spring in

place. This setscrew

must

be staked to prevent

loosening which will cause the bore evacuator and

muzzle brake thrust collar to rotate. If this screw is

not staked, notify unit maintenance.

NOTE

Setscrew (2) is removable to provide an ac-

cess to release the ball lock. It should not be

staked.

Not Fully Mission

Capable If:

Staked setscrew

is missing.

To inspect locking ball and spring, remove unstaked

screw and insert screwdriver in hole. Push against

lock ball to see if ball moves around freely. If ball

moves freely and there’s no resistance from spring,

notify unit maintenance.

Separate main reservoir (3) and prereservoir (4)

(para 3-6.7.1). Clean and lubricate three metering

orifices (5), nine evacuator ball valves (6), 10 evac-

uator holes (7), tube threads (8) and ring valve (9)

(Appendix G).

NOTE

After installing setscrew (1) notify unit mainte-

nance for torquing.

Ring valve is bro-

ken, cracked, or

deformed.

If three or more

baIls are missing.

Change 2

2-86.1