TM 9-4520-251-14
4-28 RESTRICTION INDICATOR (CONT)
Location/Item
Action
Remarks
Do not operate heater in enclosed space. Adequate ventilation is re-
quired to prevent buildup of exhaust fumes which can be toxic in con-
centrated amounts.
Wear approved ear protection equipment within 25 feet (7.6 meters) of
operating heater. Failure to do so may result in impairment or loss of
hearing.
2. Restriction
Start engine. Recheck restriction indicator window (1).
indicator
If red is visible, shut down engine and replace restric-
(after startup)
tion indicator. Press button (2) on new restriction
indicator.
Touching hot engine surfaces can cause severe burns. Protect skin
when making following test.
3.
Air filter
Restart engine. Using wadded rag, flat tool, or
intake tube
other blocking material, restrict flow of air into
intake tube (4) and observe restriction indicator.
If red is not visible, shut down engine and per-
form following steps.
REMOVAL
4.
Restriction
Unscrew from safety filter (3).
indicator
5.
Safety filter
Unscrew from pipe elbow (5).
4-64
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