Manitowoc Grove GRT9165, Service Manual

Page: 214 / 302

POWER TRAIN GRT9165 SERVICE MANUAL
7-34 Published 10-01-2020 Control # 699-00
Servicing the Crane after Transmission Overhaul
The transmission and its allied hydraulic system are
important links in the drive line between the engine and the
wheels. The proper operation of either the unit or the system
depends greatly on the condition and operation of the other;
therefore, whenever repair or overhaul of the transmission is
performed, the balance of the system must be considered
before the job can be considered completed.
After the overhauled or repaired transmission has been
installed in the crane, the oil cooler and connecting hydraulic
s y s t e m m u s t be t h o r o u g h l y c l e a n ed . T h i s c a n b e
accomplished in several ways, and a degree of good
judgment must be exercised as to the method employed.
The following are considered the minimum steps to be taken:
1. Drain the entire system thoroughly.
2. Disconnect and clean all hydraulic lines. Where feasible,
hydraulic lines should be removed from the machine for
cleaning.
3. Replace oil filter elements, cleaning out the filter cases
thoroughly.
4. The oil cooler must be thoroughly cleaned. The cooler
should be back flushed with oil and compressed air until
all foreign material has been removed. Flushing in the
direction of normal oil flow will not adequately clean the
cooler. If necessary, the cooler assembly should be
removed for cleaning, using oil, compressed air and a
steam cleaner for that purpose.
5. Remove the drain plug from the transmission and
inspect the interior of the unit housing, gears, etc. If the
presence of considerable foreign material is noted, it will
be necessary for the unit to be removed, disassembled,
and cleaned thoroughly. It is realized this entails extra
labor, however, such labor is a minor cost compared to
the cost of difficulties which can result from the presence
of such foreign material in the system.
6. Assemble all components and use only the type oil
recommended. Fill the transmission through the fill pipe
until fluid is at the top of the fill range on the dipstick. Run
the engine for two minutes at 600 rpm to 800 rpm to
prime the torque converter and hydraulic lines. Recheck
the level of oil in the transmission with the engine
running at idle (600 rpm to 800 rpm). Add oil as
necessary to bring the level to the LOW mark on the
dipstick. After the oil temperature reaches 82°C to 93°C
(180°F to 200°F), add oil to bring the level to the FULL
mark on the dipstick.
7. Recheck all drain plugs, lines, connections, etc., for
leaks and tighten where necessary.
Lubrication
Type of Oil and Capacities
Refer to Maintenance and Lubrication , page 9-1 for types of
oil, capacities, and change intervals.
Normal Transmission Fluid Period
NOTE: Normal drain periods and filter change intervals are
for average environmental and duty-cycle
conditions. Severe or sustained high operating
temperatures or very dusty atmospheric conditions
will cause accelerated deterioration and contam-
ination. For extreme conditions, judgment must be
used to determine the required change intervals.
1. Drain transmission and remove pump screen. Clean
screen thoroughly and replace, using a new gasket.
2. Remove and discard oil filter. Clean filter housing and
install new filter.
3. Refill transmission to FULL mark.
4. Run engine at 500 rpm to 600 rpm to prime converter
and lines.
5. Recheck level with engine running at 600 rpm to
800 rpm and add oil to bring level to FULL mark. When
oil temperature is hot [82°C to 93°C (180°F to 200°F)],
make final oil level check. Bring oil level to full mark.
Towing or Pushing
Before towing crane, lift the driven axle wheels off the ground
or disconnect both front and rear drive lines. Engine cannot
be started by pushing or towing because of hydraulic system
design.
CAUTION
Do not use flushing compounds for cleaning purposes.