Tennant 1550, Manual

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MAINTENANCE
1550 Gas/LPG/Diesel MM283 (12--98)
3--14
The engine is equipped with a 180
_
F (82
_
C)
thermostat. Normal engine temperature is 200
_
F (93
_
C). Temperatures up to 220
_
F (104
_
C) are allowable. Temperatures over 220
_
F
(104
_
C) indicate a problem exists.
NOTE: Overheating is always accompanied by
loss of coolant water. If in doubt, check.
A pressure cap is used on the radiator to prevent
overflow loss of water during normal operation.
The spring-loaded valve in the cap closes the
outlet to the overflow pipe of the radiator and thus
seals the system. Pressure developing within the
system raises the boiling point of the coolant and
allows higher temperatures without overflow loss
from boiling. The pressure valve opens at 15 psi
(100 kPa) allowing steam and water to pass out
the overflow pipe.
FOR SAFETY: When Servicing Machine,
Avoid Contact With Hot Engine Coolant.
AIR INTAKE SYSTEM
The importance of maintaining an air filter cannot
be overemphasized. Dirt ingested through
improperly installed, improperly serviced, or
inadequate air filter elements wears out more
engines than long hours of operation. Even a
small amount of dirt will wear out a set of piston
rings in just a few hours. Operating with a clogged
air filter element also causes the fuel mixture to
be richer, which can lead to formation of harmful
sludge deposits in the engine. Always cover the
air intake when the air filter is removed for
servicing. Do not neglect servicing the air filter.
Use only approved replacement parts. Keep all
other air intake components such as hoses and
clamps secure and in good condition to prevent
entrance of unfiltered air.
Over maintenance can cause more damage than
good. Removing the air filter element more often
than is needed allows contaminants to enter the
engine unnecessarily. Replace the air filter
element only when the restriction indicator
indicates excessive restriction in the system.
AIR FILTER SERVICE INDICATOR
The air filter service indicator signals when to
replace the air filter element. Check the service
indicator daily. The red line will move on the scale
as the air filter element fills with dirt. Do not
replace the air filter element until the red line
reaches 20 in H
2
O (5 kPa) and the “Service when
Red” window is filled with red. The service
indicator red line may return to a lower reading on
the scale when the engine is shut off. The red line
will return to a correct reading when the engine is
started.
Replace the filter element when the service
indicator reads 20 in H
2
O (5 kPa). After replacing
the air filter element, reset the service indicator by
pushing the reset button on the end of the
indicator.
A
C
B
00212
AIR FILTER RESTRICTION INDICATOR
A. Indicator Reset Button
B. Indicator Window
C. Restriction Indicator
AIR FILTER
The engine air filter housing includes a dust cap
and a dry cartridge-type air filter element. The
dust cap must be emptied of dirt daily. The air
filter element must be inspected or replaced
whenever the air filter service indicator reads 20
in H
2
O (5 kPa). The filter element must be
replaced if it is damaged.
Service the air filter element only when the air
filter service indicator shows excessive restriction
in the system. Do not remove the air filter element
unless it is restricting air flow.