TESTING HYDRAULIC SYSTEM -706880611

TM 5-4210-233-14&P-1

4-188. TESTING HYDRAULIC SYSTEM

THIS TASK COVERS:

a. Testing Hydraulic Pressure

b. Testing Aerial Performance Times

EQUIPMENT CONDITION

Engine Running and warmed up to

normal operating temperature

a. Testing Hydraulic Pressure.

(1) To test hydraulic system pressure, move the RUN/LOCK lever on the aerial control platform to the

RUN position.

(2) With all hydraulic controls in the neutral position (no hydraulic circuits actuated) the pressure indication

on the SYSTEM PRESSURE gauge should be 2150 psi (14814 kPa). Pressures higher or lower than

2150 psi (14814 kPa) indicate component failure. Troubleshoot system (refer to Table 4-2) to identify

fault. Replace or repair components as required.

b. Testing Aerial Performance Times.

(1) With all outriggers fully extended and supporting the weight of the truck (see para 2-14.) perform the

following tests. Check the aerial performance times against the times listed below.

Raise ladder from 0to 750............................

35 to 45 seconds

Lower ladder from 750 to 0...........................

35 to 45 seconds

Full left rotation (3600)................................ ....

130 to 140 seconds

Full right rotation (3600)................................ ..

130 to 140 seconds

Full extension ................................ .................

35 to 45 seconds

Full retraction ................................ .................

28 to 35 seconds

(2) Perform "three-function test". Push or pull all three aerial control levers simultaneously. Test the time

required to achieve 900 rotation, full elevation and full extension. Time required should be 1 05

seconds.

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