Gravely 991001-008, Руководство по обслуживанию

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IMPORTANT: Change the oil, oil filter, and "run-in" the
unit after any hydraulic work is performed to insure
proper lubrication and system bleed, to prevent
damage to the pumps and motors.
12.1 RUN-IN PROCEDURE
1. After maintenance is performed, set unit against a
wall and jack the drive wheels off the ground. Use
caution not to jack against the hydraulic filter.
2. Start unit and let run at the idle speed for 1 to 2
minutes to insure proper bleeding of hydraulic
pumps.
3. Next run throttle to halfway and speed control arm
forward 1/3 travel, let run for 3 to 5 minutes to
insure proper bleeding of hydraulic motors.
NOTE: It may be necessary to start the motors turning
by hand.
4. Shut off the unit and let down jack.
NOTE: In the course of operating the unit, if any
squealing noise from motors occurs, repeat the run-in
procedure.
12.2 HYDRAULIC FLOW
NOTE: The only high pressure lines are the four lines
between the pumps and motors. The only pressure
check would be to plumb in on one of the lines, and run
under normal circumstances. The pressure should
read approximately 400 psi.
12.3 FILTER CHANGE
NOTE: Be sure to replenish the oil system with clean,
fresh oil.
1. Place open container under filter. The container
should be able to hold at least 4 quarts of oil.
2. Clean around filter and turn filter counterclockwise
to remove. Let system drain sufficiently.
NOTE: Not all oil will drain.
3. Replace filter with a new Gravely filter to insure
proper oil filtering.
4. Apply a thin coat of oil to seal on filter, and hand
tighten filter securely.
5. Refer to Hydraulic System Run-In Procedure.
12.4 HYDRAULIC HOSES
IMPORTANT: When loosening any hydraulic hoses,
use the correct wrench. If hoses are to be
disconnected at a fitting, use two wrenches, one on the
hose and one on the fitting. This prevents twisting off
the fitting.
1. When working on hoses, have a container large
enough to hold at least 4 qts of oil. Some hoses will
drain one side of the hydraulic tank and/or oil
cooler.
2. After any hydraulic hose maintenance, refer to
Filter Change and Run-In Procedure sections.
12.5 HYDRAULIC TANK REMOVAL &
INSTALLATION
1. Place an open-top container that will hold at least 4
quarts of oil under the drain cock of tank. Drain
right side.
2. Move container under filter and remove.
3. Clean and remove the two hydraulic hoses from
the tank. Cap off hoses to prevent contamination of
system.
4. Remove the 1/2" nut, bolt and washer holding tank
in place.
5. Slide the bottom of the tank to the rear to remove.
6. Inspect the tank, hose ends, clamps, fittings, and
drain cock. Look for worn or damaged parts and
replace as needed.
IMPORTANT: Use a teflon pipe sealant when replacing
any fittings. Tighten down until seated flush. DO NOT
OVERTIGHTEN. Over-tightening can cause the tank to
split at the seam.
7. Reverse disassembly procedure to reassemble.
8. Refer to Hydraulic Servicing and Run-In
Procedure.
12.6 HYDRAULIC COOLER REMOVAL
& INSTALLATION
1. Loosen the clamp on the forward hydraulic hose
with an open-top container handy. Pull the hose
from the fitting and let drain. Some oil will run from
the cooler.
NOTE: If the hose is lowered it will deplete the right
side of the hydraulic tank.
2. Loosen the rear hydraulic hose by using an 11/16"
wrench along with a 5/8" wrench on the oil cooler
fitting to prevent damage from twisting the cooler
fitting off. Drain oil from line into container.
3. Remove the four bolts and lock nuts to remove the
cooler from the bracket.
4. Remove the cooler bracket by removing the two
bolts and lock nuts located between the bracket
and fuel tank.
5. Inspect and replace any worn or damaged parts.
6. Reverse the disassembly procedure to
reassemble.
7. Refer to Filter Change and Run-In Procedure.
SECTION 12 - HYDRAULIC SYSTEM