Cold Weather Engine Operation - Miller Bobcat 225 Owner's Manual

6-3.

Cold Weather Engine Operation

1 Engine Control Switch — Infrequently
Loaded
2 Engine Control Switch — Frequently
Loaded
Carburetor Icing
Carburetor icing causes the unit to drop be-
low the normal idle speed and then stall.
This condition occurs when the temperature
is near freezing and the relative humidity is
high. Ice forms on the throttle plate and inner
bore of the carburetor. The engine typically
restarts without problems but soon stalls
again.
� Treat gasoline with a fuel de-icer prod-
uct (isopropyl alcohol).
� Place the Engine Control switch in the
Run position.
� Run engine only when expecting to fre-
quently load it.
Complete Parts List available at www.MillerWelds.com
�
Complete Parts List is available at www.MillerWelds.com
1
Breather Icing
Oil breather/pulse line icing occurs in severe
cold (continuously below 0°F). Moisture ac-
cumulates in the oil from piston ring blow-by
if the engine is extensively idled. This may
cause vacuum line freezing, oil breather
tube freezing or ice in the carburetor. All of
these cause operating problems. Due to ice
in the lines, the engine may not restart until
it is warmed to above freezing.
� Load engine and reduce idle times to
prevent engine shutdowns.
� Use an electric fuel pump to avoid pulse
line freezing.
� Install engine cold-weather kit.
Kohler (1-800-544-2444) offers a kit for cold
weather operation. The user can install this
kit. The kit pulls heated air from the muffler
surface into the carburetor and shut the cold
2
Ref. 236615-A
air off. This increases engine temperature
during operation in both idle and high speed.
�
When the ambient temperatures be-
come warmer (above 45°F) the air flow
will have to be returned to normal.
Synthetic Oil
For temperatures below zero (0° F), syn-
thetic oil improves engine starting. After the
first 50 hours of operation with non-synthetic
oil, the engine can be switched to synthetic
oil.
�
Do not extend the 100 hour recom-
mended oil change interval.
In severe cold, use synthetic grade 5W30
oil. See engine maintenance label for addi-
tional information.
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