PILOT VALVE - ADJUST/REPLACE

TM 5-4930-233-14

TM 4930-1411

AIR COMPRESSOR ASSEMBLY

4-27. PILOT VALVE - ADJUST/REPLACE

This task covers:

a. Adjustment

b. Removal

Installation

INITIAL SET-UP:

Materials/Parts

Tools

Teflon tape

General Mechanics Tool Box

(Item 18, App E)

(Section III, Item 1, App B)

Adjustment

(1)

To raise or lower the pressure range without increasing or decreasing the spread of the range, loosen the

outside lock nut (1), and turn the adjusting screw (2). If you turn the adjusting screw clockwise, you will

increase the pressure. Turning it counterclockwise will decrease the pressure.

(2)

To adjust the spread of the range (that is, to increase or decrease the difference between the cut-in and cut-

out pressure), you should loosen the inner lock nut (3) and rotate the adjusting barrel (4). Turning the barrel

clockwise will increase the spread between cut-in and cut-out pressures. Turning it counterclockwise will

decrease the spread.

CAUTION

Do not leave the adjusting barrel (4) screwed down to the bottom position. It will prevent the pilot

valve from controlling

(3)

If the overall range is too high or too low after adjusting the spread of the range, you must readjust the

adjusting screw (2) as required. Tighten all lock nuts after making the adjustments.

(4)

Replace the pilot valve if you cannot adjust it to control the pressure properly.

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