OPERATION IN EXTREME HEAT

TM 3-1040-279-12&P

CAUTION

Do not hold ENGINE or FOG OIL switch in START position for more than 15

seconds.

(b) Hold ENGINE switch in START position until ENGINE indicator lights.

switch in START position).

(d) When FOG OIL indicator lights, move ENGINE and FOG OIL switches to RUN position.

(e) After FOG OIL indicator lights, adjust FOG OIL FLOW control knob to obtain an operating

temperature of 650 -950F (343-510%).

CAUTION

Do not repeat steps (b) through (d) more than 3 times if engine fails to start.

(f)

If thermal switch stops pulse jet engine before FOG OIL indicator lights, move all switches to

OFF, wait until SMOKE TEMP indicates 650F, and then perform steps (a) through (d) again.

If after 3 attempts FOG OIL indicator does not light, move all switches and CB1 to OFF

position and notify organizational maintenance.

2-11 OPERATION IN EXTREME HEAT

The following procedures are for operating the M157 smoke generator set in temperatures above 90F

(32C).

a. Adjustments. For missions where the average operating temperature is expected to be 90F or

above, request organizational maintenance to adjust the fog oil pump assembly pressure relief valve to 25

psig. Refer to page 4-145. If the operating temperature during a mission would unexpectedly drop below

9OF, it is not necessary to stop the mission. Proper adjustment should be made when time permits.

WARNING

Control panel may become very hot when operating at temperatures above

95F. Do not touch control panel with bare hands. Wear gloves (App E).

b. Starting in Extreme Heat. This procedure should also be used when restarting a hot generator

(SMOKE TEMP indicator above 650 F).

(1) Follow steps 2-9a (1 through 5) for starting under usual conditions (P. 2-10.6).

(2) Preset FOG OIL FLOW control knob to a level that will deliver fog oil at a rate that will ensure

normal operation. If unknown, set to 5.

(3) Hold both ENGINE and FOG OIL switches to the START (up) position at the same time until their

indicators light. When indicators are lit, release switches and allow them to move to the RUN

(center) position.

(4) Adjust FOG OIL FLOW control knob for normal engine temperature and optimum smoke

production.

Change 4