Note:
Generally, cylinder heads wear out at different
rates. Sometimes, servicing the cylinder heads at
different times may be the most economic decision.
The decision depends on the valve recession of the
individual cylinders. However, this decision must
include the costs of extra downtime that is caused by
this procedure. Perform an economic analysis to
determine if cylinder heads should be serviced as a
group or divided into smaller groups.
Top End Overhaul Information
A top end overhaul involves servicing the cylinder
heads. During a top end overhaul, one piston should
be removed. Inspect the piston, piston rings, and the
cylinder liner. The condition of these components will
determine the period of the major overhaul.
Contact your Perkins distributor or Perkins dealer for
more information.
Monitoring Valve Seat Wear
At the required service interval, record the valve lash.
1.
Remove the rocker covers.
2.
Refer to Operation and Maintenance Manual,
“Valve Lash - Inspect Adjust”.
3.
On all engine cylinders, record the clearance
before any adjustments are made.
4.
Set the valve bridges.
5.
Adjust the valve lash to 0.4 mm (0.016 inch).
Note:
After the engine valve lash is recorded,
Perkins recommends that the valve depth is
measured and recorded.
The valve depth is to be measured at every service.
The valve recession can then be calculated. The
values can be used to schedule a top end overhaul.
Note:
Perkins recommends that the valve depth is to
be measured before the installation of new cylinder
heads or during the commissioning of the engine to
obtain a baseline measurement.
The valve recession tool has been designed to give
service personnel a good indication of the cylinder
head valve recession or cylinder head valve seat
wear without the need to remove the cylinder heads.
For more information contact Perkins distributor.
Note:
For earlier engines, the maximum permitted
inlet and exhaust valve seat wear is 1.00 mm
(0.040 inch).
Note:
For later engines, the maximum permitted inlet
and exhaust valve seat wear is 2 mm (0.080 inch).
Do not allow the recession of the valves to exceed
these limits.
i02415302
Radiator - Clean
Note:
Adjust the frequency of cleaning according to
the effects of the operating environment.
Inspect the radiator for these items: Damaged fins,
corrosion, dirt, grease, insects, leaves, oil and other
debris. Clean the radiator, if necessary.
Personal injury can result from air pressure.
Personal injury can result without following prop-
er procedure. When using pressure air, wear a
protective face shield and protective clothing.
Maximum air pressure at the nozzle must be less
than 205 kPa (30 psi) for cleaning purposes.
Pressurized air is the preferred method for removing
loose debris. Direct the air in the opposite direction to
the fan's air flow. Hold the nozzle approximately
6 mm (0.25 inch) away from the radiator fins. Slowly
move the air nozzle in a direction that is parallel with
the radiator tube assembly. This will remove debris
that is between the tubes.
Pressurized water may also be used for cleaning.
The maximum water pressure for cleaning purposes
must be less than 275 kPa (40 psi). Use pressurized
water in order to soften mud. Clean the core from
both sides.
Use a degreaser and steam for removal of oil and
grease. Clean both sides of the core. Wash the core
with detergent and hot water. Thoroughly rinse the
core with clean water.
After cleaning the radiator, start the engine. Run the
engine. This will help in the removal of debris and the
drying of the core. Stop the engine. Use a light bulb
behind the core in order to inspect the core for
cleanliness. Repeat the cleaning, if necessary.
Inspect the fins for damage. Bent fins may be opened
with a “comb”. Inspect these items for good condition:
Welds, mounting brackets, air lines, connections,
clamps and seals. Make repairs, if necessary.
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