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MTH 392E Operating Manual
TINPLA
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PROTOSMOKE™ UNIT OPERATION
The 392E contains a self-powered smoke unit that outputs a steady stream of smoke through
the smoke stack on the roof of the engine. The ON/OFF switch located inside the engine cab
must be in the ON position in order for the smoke unit to function. See Fig. 1 on page 3.
The smoke unit is essentially a small heating element and wick which soaks up and then
cooks" a mineral oil-based fluid that omits a harmless smoke. The smoke is then forced out
of the stack via a small electric fan which runs at a constant speed. However, the smoke
intensity can be varied by increasing the transformer voltage setting. The higher the setting,
the more intense the smoke output.
For best results, we recommend that you add 15 - 20 drops of ProtoSmoke, Seuthe, LGB or
LVTS fluid before you run the engine. If you dont choose to add the fluid, then the smoke
unit switch should be turned off. Failure to either add the fluid or turn the switch off could
lead to damage to the smoke unit heating element and or wicking. Add the fluid through the
smoke stack hole. After adding the fluid, gently blow into the stack to eliminate any air
bubbles. Do not overfill the unit as overfilling can cause the fluid to leak out and coat the
interior engine components. When the smoke output begins to diminish while running the
engine, an additional 10-15 drops of smoke fluid should be added or the smoke unit switch
should be turned off. When storing the engine for long periods of time, you may want to add at
least 15 drops of fluid to keep the wick soaked with fluid and prevent it from drying out. After
removing the engine from storage, it is advisable to add another 25 drops of fluid, letting the
wick soak up the fluid for 15 minutes prior to operation.
MAINTENANCE
CAUTION:
Operating the engine without smoke fluid and with the smoke unit switch in the
ON position can damage your smoke unit wick, causing the wick to become hard, blackened
and unabsorbant around the heating
element. When this occurs, it may be
difficult for the wick to soak up the smoke
fluid resulting in poor or no smoke
output. If that occurs, we recommend
that you inspect and/or replace the wick
taking care to not run the engine without
fluid in the future. You can inspect the
wick to see if it needs replacement by
removing the smoke unit inspection cover
from the body as seen in Fig. 2. After
removing the chassis and inspection
cover screws lift the inspection plate
away and inspect the wick. If the wick is
darkly discolored and hard, it should be
replaced.
Smoke Unit
Circuit Board
Mounting Screws
After Removing
Mounting Screws,
Lift Circuit Board
To Reveal Wicking
Figure 2: Inspecting The Smoke Unit
