Setting Hydraulic Pressures; Main Relief Valve; Setting Main Relief Pressure - Snorkel A38E Parts & Service Manual

Section
4.5
2. Provide a suitable container to catch the
drained oil. Hydraulic tank has a capacity of 25
Litres (6.5 Gallons US).
3. Remove the drain plug on the lower side and
allow all oil to drain.
4. Clean the magnetic drain plug and reinstall.
5. Disconnect the return hose and hose fitting
from inlet port of the hydraulic return filter.
Loosen and remove the filter cover retaining
bolts. Remove filter (10 micron) assembly.
Replace with a new filter.
6. Fill the hydraulic reservoir with hydraulic oil
(see Section 1-2) checking level with dipstick.
7. Recycle used oil as per local environmental
regulations.
Filter Housing
Cover
Filter
Element
Filter
Housing
DRAIN
PLUG
Figure 4-2: Oil and Filter Replacement
Pressure
Test Point
Main Relief
Valve
Figure 4-3: Manifold Block
4-6
Maintenance
Filler Cap With
Dipstick
Slew Cross
Line Relief
Valve

4.5 Setting Hydraulic Pressures

(Figure 4-3)
Check the hydraulic pressures whenever the pump,
manifold or relief valve have been serviced or
replaced.
WARNING
The hydraulic oil may be of sufficient
temperature to cause burns. Wear safety
gloves and safety glasses when handling hot
oil. The oil in the hydraulic system is under
very high pressure which can easily cause
severe cuts. Obtain medical assistance
immediately if cut by hydraulic oil.
MAIN RELIEF VALVE (Figure 4-3,4)
1. Operate the hydraulic system for 10-15 minutes
to warm the oil.
2. Remove the cover from the Chassis body.
3. Insert pressure gauge into the high pressure
gauge port (TP) on the Manifold Block.
4. Loosen locknut on main relief valve and turn
adjusting screw anticlockwise two full turns
using a 4 mm Allen key.
5. Operate the Telescope RETRACT function
switch from lower controls and keep it
activated.
6. Slowly turn the main relief valve adjusting screw
clockwise until the pressure gauge reads 145
Bar (2105 p.s.i.) pressure.
7. Release the Telescope RETRACT switch.
8. Tighten locknut on main relief valve while
holding the adjusting screw in position.
Figure 4-4: Setting Main Relief Pressures
AB38 Work Platform