Operation In Hot And Humid Conditions; Operation In Extremely Dusty Conditions; Lubrication; Electrical System - Hobart JET-EX 4 Operation And Maintenance Manual

(5) Lubrication

Drain the crankcase (preferably when warm after running) and fill with a lighter grade of oil. See
Engine Oil Recommendations chart in the Maintenance and Operator's Manual for recommended
viscosity for various atmospheric temperatures. In cold weather, drain oil more frequently. Water
condenses and collects quickly, mixes with the oil and increases deposits to form a sludge. Check
oil frequently for this condition. Water in crankcase or oil lines may freeze and cause serious dam-
age to the oil pump, or shut off the oil supply.

(6) Electrical system

In cold weather, the most efficient electrical system is needed to start the cold engine. Check the
entire system for loose connections or indication of bad wiring or shorted conditions. Check spark
gaps of the spark plugs, and distributor point gaps, consult the Maintenance and Operator's Man-
ual for the engine.

(7) Battery

Battery efficiency decreases sharply with lower temperatures. Maintain the specific gravity of the
battery between 1.275 and 1.300 (fully charged condition). Make sure of full charge before at-
tempting to start engine in sub-zero conditions.
H. Operation in Hot and Humid Conditions

(1) Cooling system

Maintain a more frequent check of the coolant level in the radiator.
(2) Battery
The specific gravity and proper level of the battery electrolyte should be maintained. Observe rec-
ommendations in the Maintenance and Operator's Engine Manual for proper care of the battery.
I. Operation in Extremely Dusty Conditions
If unit is to be operated under dusty, out-of-door conditions, place in a sheltered area. Take advan-
tage of any natural barriers which may offer protection from blowing dust. If the installation is more
than temporary, erect a protection shield.

(1) Fuel system

Change the fuel pump filter regularly and keep all fuel containers covered and protected against
dust entry.

(2) Oil filter and air cleaner

These both need more frequent attention under dusty conditions. Check air cleaner daily. Re-
place oil filter cartridge as needed.

(3) Crankcase

The crankcase oil level will bear close attention. Dusty conditions tend to load crankcase oil with
dirt. Watch for dirty and gritty oil conditions, and change oil more frequently as required.
May 20/89
OM-2049
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