Hobart 140GT17K, Operation And Maintenance Manual With Illustrated Parts List

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(3) Engine protective devices
(a) High coolant temperature switch
A high coolant temperature switch (18, Fig. 3) is mounted at the rear of the engine to monitor
the coolant temperature. If the coolant temperature reaches 210 degrees F (99 degrees C) ,
this normally closed switch opens and actuates the fuel valve solenoid which shuts down the
engine.
(b) Oil pressure switch
A diaphragm-type switch monitors the pressure in the lubricating oil system. It is mounted in
the side of the cylinder block
(16, Fig. 3) . If the pressure in the lube oil system falls to 10 psi
(69 kPa) , this switch opens and actuates the fuel valve solenoid which shuts down the engine.
(4) Air cleaner
The diesel-engine air cleaner (Fig. 4) is a dry-cartridge type. It is equipped with a moisture elimina-
tor and a service indicator. The indicator functions to signal the operator when the cartridge needs
changing. A red cylindrical “flag”
(2)
is forced upward in a glass enclosed viewing chamber
(1)
when air pressure within the air cleaner housing drops below the outside air pressure. As the car-
tridge becomes loaded with dirt and air pressure within the cleaner lessens, the “flag” gradually
rises higher in the glass viewing chamber. When the “flag” reaches the top of the chamber, it
locks in that position to warn the operator that the cartridge must be changed. The “flag” is reset
(unlocked) by pushing the reset button (3) located on the bottom of the indicator.
NOTE: The service indicator is mounted on the engine control panel and connected to the air cleaner
by a rubber hose. The indicator flag is visible only when the engine is running, or when the flag is locked
in WARNING position.
1. Viewing chamber
2. Indicating “flag”
3. Reset button
Air Cleaner and
ServiceIndicator
Figure 4
OM-2029
September 30/89 Revised 1-1
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