Hydraulic System Maintenance; Hydraulic Fluid Specifications - Toro STX-38 Operator's Manual

Adjusting the Traction-Control
Neutral Position
If the machine creeps forward or backward when
the traction control is in neutral and the machine is
warm, you may need to adjust the return-to-neutral
mechanism on the pumps; contact your Authorized
Service Dealer.
Adjusting the Traction-Control
Forward Position
If the machine does not drive straight when you hold
the traction control forward against the reference bar,
complete the following procedure:
1. Drive the machine with the traction control
against the reference bar, noting which direction
the machine veers.
2. Release the traction control.
3. If the machine veers to the left, loosen the right
jam nut and adjust the tracking set screw on the
front of the traction control
4. If the machine veers to the right, loosen the left
jam nut and adjust the tracking set screw on the
front of the traction control
Figure 58
1. Set screw
2. Jam nut
5. Repeat the procedure until the machine drives
straight in the full forward position.
Important:
Ensure that the set screws touch
the stops in the full forward position to avoid
overstroking the hydraulic pumps.
(Figure 58).
(Figure 58).
g004194
3. Stop
Hydraulic System
Maintenance
WARNING
Hydraulic fluid escaping under pressure can
penetrate skin and cause injury. Fluid injected
into the skin must be surgically removed
within a few hours by a doctor familiar with
this form of injury; otherwise, gangrene may
result.
• Keep your body and hands away from
pinhole leaks or nozzles that eject
high-pressure hydraulic fluid.
• Use cardboard or paper to find hydraulic
leaks; never use your hands.
Hydraulic Fluid
Specifications
Hydraulic Tank Capacity: 38 L (10 US gallons)
Use Toro Premium All Season Hydraulic Oil (refer
to your Authorized Toro Dealer for more information).
Alternative fluids: If the Toro fluid is not available,
other conventional, petroleum-based fluids may
be used, provided they meet all of the following
material properties and industry specifications.
Check with your oil supplier to see whether the
oil meets these specifications. Note: Toro will
not assume responsibility for damage caused by
improper substitutions, so use only products from
reputable manufacturers who will stand behind their
recommendation.
High Viscosity Index/Low Pour Point Anti-wear Hydraulic
Fluid, ISO VG 46
Material Properties:
Viscosity, ASTM D445
Viscosity Index ASTM
D2270
Pour Point, ASTM D97 -37°C to -45°C (-34°F to -49°F)
FZG, Fail stage
Water content (new
fluid):
Industry Specifications:
Vickers I-286-S, Vickers M-2950-S, Denison HF-0, Vickers
35 VQ 25 (Eaton ATS373-C)
The proper hydraulic fluids must be specified for
mobile machinery (as opposed to industrial plant
usage), multi-weight type, with ZnDTP or ZDDP
anti-wear additive package (not an ashless-type fluid).
Important:
Many hydraulic fluids are almost
colorless, making it difficult to spot leaks. A
red dye additive for the hydraulic system oil is
available in 20 ml (0.67 fl oz) bottles. One bottle
37
cSt @ 40°C (104°F) 44 to 48
cSt @ 100°C (212°F) 7.9 to 9.1
140 or higher
11 or better
500 ppm (maximum)