Belarus 820 - Page 357

80-0000010B OM
357
End of Table 7.7.1
Failure,
external manifestation, cause
Troubleshooting
Pressure regulator engages compressor for idle stroke when pressure is below 0.77...0.80
MPa, and for o
p
eratin
g
stroke when
p
ressure is below 0.65 MPa or over 0.70 MPa
Dirt accumulation in cavities and
channels of
p
ressure re
g
ulato
r
Rinse and clean the pressure regulato
r
Faulty location of the pressure regula-
tor adjusting cap
A
djust pressure regulator as indicated in section 3.8.3
“Check and adjustment of pneumatic system pressure
regulator”
Damage of rubber parts of pressure
regulator, spring shrinkage
Replace damaged parts or send the pressure regulator
to a repair workshop
Tilting, sticking of spool of the pressure
regulator adjusting part
Ensure free movement of spool, lubricate it or send
pressure regulator to a repair workshop
Pressure regulator goes off frequently (engages the pneumatic compressor)
without air bleedin
g
from the receiver tank
A
ir leakage from the pneumatic system
or from the pressure regulator, failure of
the
p
ressure re
g
ulator backflow valve
Detect and stop air leakages
Pressure re
g
ulator o
p
erates in the mode of safet
y
valve
Pressure regulator adjusting cap is
turned in to a big value
A
djust pressure regulator as indicated in section
3.8.3 “Check and adjustment of pneumatic system
p
ressure re
g
ulator”
Jamming of pressure regulator
dumm
y
p
iston
Disassemble pressure regulator and eliminate jam-
min
g
Outlet ports in the pressure regula-
tor ad
j
ustin
g
ca
p
are clo
gg
ed
Unclog outlet ports
There is no air feeding into the connecting hose through air bleeding valve of
p
ressure re
g
ulato
r
Insufficient sinking of air bleeding
valve rod in the
p
ressure re
g
ulato
r
Screw in entirely the nut of the connecting hose on
the fittin
g
Pressure regulator has switched the
pneumatic compressor to idle stroke
Decrease pressure in the receiver tank to the value
below 0.65 MPa
Ineffective brakin
g
of trailed a
g
ricultural im
p
lement
Faulty adjustment of brake valve
drive
A
djust the brake valve drive as specified in section
3.8.2.2 “Check and adjustment of pneumatic system
brake valve drive”
Brake valve failure Re
p
lace brake valve
Failure in the brake system of the
trailed agricultural implement
Eliminate the failure in the brake system of the trailed
agricultural implement
Brakes of trailed a
g
ricultural im
p
lement release slowl
y
Brake valve drive got misadjusted
A
djust the brake valve drive as specified in section
3.8.2.2 “Check and adjustment of pneumatic system
brake valve drive”
Brake valve failure Replace brake valve
Failure in the trailer brake system Eliminate the failure in the brake system of the trailed
agricultural implement
ATTENTION: WHILE TROUBLESHOOTING IN THE PNEUMATIC SYSTEM, ALL SELF-
MAINTAINED OPERATIONS RELATED TO PRESSURE REGULATOR ADJUSTMENT AND RE-
PAIR, ARE ALLOWED ONLY AFTER THE END OF TRACTOR WARRANTY PERIOD. OTHER-
WISE THE WARRANTY FOR THE PRESSURE REGULATOR SHALL BECOME VOID. TO RE-
PAIR OR ADJUST YOUR PRESSURE REGULATOR (INCLUDING DURING TM3) DURING
TRACTOR WARRANTY PERIOD CONTACT YOUR DEALER!