Komatsu 830E-AC Shop Manual page 133

REPAIRING THE RADIATOR
Radiator service is a specialized function usually not
accomplished by most maintenance shops. The
large size and weight of the off-road truck radiators
requires that a radiator repair shop equipped with
special tools and handling equipment be used for
service and repair.
Internal Inspection
If desired, an internal inspection can be performed on
the radiator before complete disassembly. The
inspection involves removing tubes from the radiator
core and cutting them open. This type of inspection
can indicate overall radiator condition, as well as
coolant and additive breakdown.
To perform this inspection, remove four random
tubes from the air inlet side of the radiator. Remove
tubes from both the top and bottom cores, and near
each end of the radiator. Refer to Disassembly and
Assembly in this section for the proper instructions
for removing and installing tubes. Analyze any
contaminant residue inside the tube to determine the
cause of contamination. Flush the system before
returning the truck to service. Contact your nearest
L&M Radiator facility for further instructions or visit
the L&M website at www.mesabi.com.
External Cleaning
Many radiator shops use a hot alkaline soap, caustic
soda or chemical additives in their boil-out tanks,
which can attack solders. These tanks are generally
not recommended. Before such tanks are used for
cleaning, ensure that the cleaning solutions are
not harmful to solder. Otherwise, damage to the
radiator will result. Completely rinse the cleaned
tube or core in clean water after removing it from the
boil-out tank.
As an alternative to boil-out tanks, radiators can be
cleaned externally with a high pressure washer and
soap. In most cases, it may be best to blow out any
dry dirt with a high pressure air gun prior to washing
the core with the high pressure washer.
C03035
Pressure washers should not exceed 8275 kPa
(1200 psi). Unlike conventional cores, the spray
nozzle can be used right up next to the core. Starting
from the air exit side, place the high pressure washer
nozzle next to the fins. Concentrate on a small area,
slowly working from the top down. Spray straight into
the core, not at an angle. Continue washing until the
exit water is free of dirt. Repeat from the opposite
side.
Disassembly
To aid in removal of the tubes, clean the radiator
prior to disassembly. Heating the seals with hot
water helps to loosen the grip on the tubes.
Cleaning the radiator prior to disassembly also
reduces the risk of internal contamination. After
cleaning, spray lubricating oil at the top end of
the tubes.
FIGURE 3-5. BREAKER TOOL (XA2307)
1. Start at the top row of tubes. Use the breaker
tool (XA2307) to loosen the tube to be removed.
When using the breaker tool, position it at the
top or bottom of the tube. Never position it in the
middle of the tube or damage may result. Use
the breaker tool to lightly twist the tube back
and forth within the seals to loosen the grip.
Refer to Figure 3-5.
Cooling System C3-9