Dealer Service 25; Hydraulic Valve Repair - Woods BH85 Operator's Manual

The information in this section is written for dealer ser-
vice personnel. The repair described here requires
special skills and tools. If your shop is not properly
equipped or your mechanics are not properly trained in
this type of repair, it may be more time and cost effec-
tive to replace complete assemblies.
 Keep hands and body away from pressurized
lines. Use paper or cardboard, not hands or other
body parts to check for leaks. Wear safety goggles.
Hydraulic fluid under pressure can easily penetrate
skin and will cause serious injury or death.
 Make sure that all operating and service person-
nel know that if hydraulic fluid penetrates skin, it
must be surgically removed as soon as possible by
a doctor familiar with this form of injury or gan-
grene, serious injury, or death will result.
CONTACT A PHYSICIAN IMMEDIATELY IF FLUID
ENTERS SKIN OR EYES. DO NOT DELAY.
 Before working on backhoe, extend boom and
dipperstick and place bucket on ground. Shut off
tractor engine. Make sure that all system pressure
has been relieved by operating controls before
maintenance, service, or disconnecting any
hydraulic lines.
CAUTION
 Always wear relatively tight and belted clothing
to avoid getting caught in moving parts. Wear
sturdy, rough-soled work shoes and protective
equipment for eyes, hair, hands, hearing, and head;
and respirator or filter mask where appropriate.
 Never strike a pivot pin or punch with a nail
hammer because the face may chip, possibly
resulting in an eye or other serious injury. Use a
soft face hammer.
BH85 & BH100
HYDRAULIC VALVE REPAIR (FIGURE 20)
Valve repair should be accomplished in a clean work
place. Photograph or note the configuration of the parts
before disassembling valve and control linkage. This
will make reassembly easier.
MAN1272 (10/22/2019)
DEALER SERVICE
ARNING
System Relief Valve
 Adjustment of system relief pressure must be
done by a qualified, experienced dealership. Incor-
rect adjustment can result in system failures and
serious personal injury.
No individual parts are available for relief valve.
Replace entire assembly if required.
Pressure Setting Adjustment
NOTE: Before changing the pressure setting on the
valve, determine tractor hydraulic system pressure.
Many tractors do not create 2500 psi. If your tractor
does not create 2500 psi, changing the relief valve set-
ting will not improve the backhoe performance.
To adjust relief valve setting, place a 3000 psi pressure
gauge in the line attached to the valve inlet (IN) port.
Remove cap from top of main relief (6, Figure 20). Turn
adjusting screw clockwise to increase pressure and
counter clockwise to decrease pressure. Start tractor
and set throttle for full engine speed. Move right stabi-
lizer control lever to raise stabilizer to transport position
and hold the lever so full pressure builds. Adjust screw
to attain 2465 psi for BH85 & BH100. Shut off tractor
and replace cap.
Port Relief Valves
Pressure settings on port relief valves are preset at the
factory. Although they are adjustable, they must not be
reset in the field using backhoe hydraulic system. An
incorrect setting could cause hydraulic pump to fail or
backhoe cylinder rods to buckle.
Replace Port Relief Valves
It is not necessary to remove the entire valve assembly
from the console to replace individual port relief valves.
Be sure to install valve cartridges set at the correct
pressure. Valves are similar and can be easily mixed
up.
IMPORTANT: Valve cartridges have small sealing
washers attached to them. When replacing valve,
check cavity in valve housing for any loose washers.
Port Relief Valve
Cartridge 8
Cartridge 7
Cartridge 9
Load Check Valve Replacement
The load check valves (11) are located between the
valve work ports. Remove load check assembly using

Dealer Service 25

ARNING
Pressure Setting
2465 psi
2610 psi
3045 psi