CHAPTER 5 DIRECT SUPPORT MAINTENANCE INSTRUCTIONS

TM 3-4240-201-13

CHAPTER 5

DIRECT SUPPORT MAINTENANCE INSTRUCTIONS

Section I. PRECLEANER AND HOUSING ASSEMBLY

5-1.

Description

Inspect the steel housing of the precleaner and housing

assembly for dents, cracks, and other damage.

The M1A1 air purifier precleaner (fig. 5-1) consists of an

electric-motor-driven centrifugal fan, a dust separator, a

5-3.

Disassembly, Repair, Assembly, Installation,

mounting plate, rubber channel seals, lockwashers, and

screws.

The centrifugal fan includes an electrical

and Test

receptacle connector and cup switch. The electric motor

operates on 30 volts ac or 24 volts dc electrical power.

a. End Plate. Remove six screws, lockwashers,

When the electric motor is operating, the centrifugal fan

and nuts that hold the end plate in the housing. Remove

draws in air through eight openings in the purifier

four screws and washers that hold switch cup to the

housing. It blows the air into the dust separator, which

housing. Insert a brass nonmetallic drift pin through the

traps the dust. The air then flows from the dust

switch cup hole in the housing against the inside surface

separator through two large holes in the housing

of the end plate. Use a hammer against the drift pin and

bulkhead. Also, dirt trapped by the dust separator is

drive the end plate free of the housing. Examine the

blown from the air purifier through two outlets in the end

rubber grommets to make sure they are not deteriorated.

plate. The air deflector, which is mounted on the filter

Remove the grommets by working them free of the end

side of the housing bulkhead, deflects the airstream so

plate (fig. 5-1). Clean all parts as necessary. Discard all

that the air flows evenly through all parts of the

faulty parts and replace with new ones.

particulate filter rather than through a small area of the

b. M1A1 Air Purifier Precleaner. If repair

filter.

5-2.

Inspection

Figure 5-1. Precleaner and housing assembly.

5-1