Belarus 820 - 7.12 Possible failures of hydraulic lift linkage and instructions for troubleshooting

80-0000010B OM
366
7.12 Possible failures of hydraulic lift linkage and instructions for trouble-
shooting
A list of possible failures of the hydraulic lift linkage and instructions for their trou-
bleshooting are given in Table 7.12.
Table 7.12
Failure,
external manifestation, cause
Troubleshooting
RLL with agricultural implement attached will not rise
No pressure in the hydraulics:
 sticking of bypass valve;
Remove the valve parts, rinse and install into the
body. The valve must move freely
 clogging of safety valve;
Disassemble the safety valve, rinse, reinstall. Adjust the
valve actuation pressure.
 insufficient amount of oil in the
tank.
Add oil to the tank to the recommended level
Loss of pump efficiency Check pump performance, replace if necessary.
Regulator control rod length is
maladjusted
Adjust
Weight of the implement exceeds
the allowable value for the tractor
lift linkage
Use agricultural implements, as agreed with the manu-
facturer
No forced lift linkage lowering
Regulator control rod is improper-
ly adjusted
Adjust
Slow rise of lifting linkage with agricultural implement attached
Air suction into the hydraulic sys-
tem
Identify place of suction and eliminate the failure
Loss of pump performance Check pump performance, replace if necessary.
Weight of the implement exceeds
the allowable value for the tractor
lift linkage
Use agricultural implements, as agreed with the manu-
facturer
Oil foaming in oil tank and spitting through the breather
Air suction into the hydraulic sys-
tem through the suction line
Tighten the connection and replace the gaskets of
suction pipe branch if necessary
Air suction through self-tightening
cuffs of the HLL oil pump
Check condition of self-tightening cuffs and replace if
necessary.
Oil level in the tank is too high Drain excess oil to recommended level.
Increased oil heating during system operation
Insufficient oil in the tank Add oil to the tank to the recommended level.
Oil lines bent or crumpled Repair the crumples or replace oil line
Sticking of spool of hydraulic dis-
tributor
Return the levers of hydraulic distributor to the neutral
position after finishing the operation
Hydraulic motors of the imple-
ment are not in agreement with
the tractor pump feed in terms of
consumption
Apply implements as agreed with the manufacturer