SM01-002-0
Page 5
SYMPTOM
PROBABLE CAUSE
SOLUTION
1. Engine overheating (continued).
g. Engine overloaded.
g. Operate engine in proper load
range.
h. Stiff rebuilt engine.
h. Break-in engine properly
2. Overcooling
a. Thermostat not installed.
a. Install thermostat.
b. Damaged thermostat stuck open.
b. Replace thermostat.
c.
Warm up engine properly.
c.
Short runs and intermittent driving.
G EN ER AL
system. Most of these problems will be traced to
ov erheating; howev er, an engine that is running
The cooling system includes the radiator,
too cold can be just as troublesome.
thermostat, the fan, and water pump driv e belts.
O ve r he a t i ng .
Radiator hoses are also included in this group.
Because the effects or damage that result from an
An engine that is ov erheating may lead to troubles
improperly maintained cooling system usually
such as the following.
occur gradually, this system is often times
neglected. Howev er, the cooling system must be
1.
Burned v alves.
treated with the same attention to maintenance as
is giv en such other systems as fuel, air, and
2.
Pinging or knocking.
brakes. A review of the cooling system's function
will show this more clearly.
3.
Excessiv e fuel consumption.
In general, the circulation of water through the
4.
Poor lubrication - increased engine wear.
cooling system relies entirely upon the water
pump. The water pump draws water from the
5.
Sticking v alves.
radiator and forces it through the water jackets and
cylinder head. There it accumulates heat. Then the
6.
Short injector life.
water flows to the upper radiator tank and down
through the radiator core, being cooled by air from
7.
Engine hot spots.
the fan. This process of removing heat from water
as it circulates holds the engine to its efficient
8.
Need for higher grade fuel.
operating temperature.
O ve rc o o l i ng .
The following paragraphs point out sev eral facts
about cooling system components, the effects of
The following engine troubles result when an
cooling system neglect, and procedures to be
engine is ov ercooled.
followed for cooling system maintenance.
1.
Excessiv e fuel consumption.
EFFECTS OF COOLING SYSTEM NEGLECT.
2.
Sludge formation in crankcase.
Whenev er an engine does not perform at top
efficiency, neglected cooling system may be at
3.
Corrosiv e acids formed in crankcase.
fault ev en though the engine part directly
responsible is not ev en a part of the cooling
4.
Excessive fuel deposits in the exhaust system.
