Page 51
472H Potato Harvester Owner Operator’s Manual
4.4.3 CHANGING HYDRAULIC OIL FILTER USED IN THE ELECTRO-HYDRAULIC VALVES
The major cause of hydraulic valve failure is contaminants
such as dirt, rust, metal filings or sludge. Contaminants
cause valve spools to stick, plug small passages, or erode
components until the valve leaks. When servicing the valves
take extreme measures to keep the valve components clean.
To prevent hydraulic valve failure,
FILTER ELEMENT
SHOULD BE REPLACED
at the beginning of every season.
(See Fig. #65)
WARNING
Injury or death may result if a cylinder loses pressure
and suddenly retracts or extends. Block up or lower
the nose lift and the coulters. Move the control switches
to release the pressure in the system before discon-
necting any hydraulic connections.
WARNING
Hydraulic fluid under pressure can pierce the skin, caus-
ing injury or death. Do not expose bare skin to pressur-
ized hydraulic fluid. Use eye protection and appropri-
ate protective clothing to prevent injury. If skin is punc-
tured, seek medical help immediately.
WARNING
Disconnect the tractor battery cables by first removing
the negative cable from the terminal post then remov-
ing the positive cable to eliminate accidental actuation
of the valves or shorting tools out.
Fig. #65
15
LS
14
13
P
19
16
18
17
20
22
21
B
A
X
X
X
X
X
X
.
I N
C
Y
H
D
R
C
A
F
O
E
R
B
A
X
X
X
X
X
X
.
I N
C
Y
H
D
R
C
A
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O
E
R
B
A
X
X
X
X
X
X
.
I N
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D
R
C
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X
.
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I
NC
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I
NC
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A
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.
I
NC
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R
NOTE: VALVE SHOWN IN OPEN CENTER (STANDARD) CONFIGURATION,
FOR CLOSED CENTER OPERATION, SWITCH CARTRIDGE #10 AND PLUG #14
3
2
1
SEE YOUR DEALER FOR LOAD SENSING OPERATIONS.
ITEM
PART NUMBER
DESCRIPTION
SEAL KIT PART NUMBER
1
14148-00
FILTER, HYDRAULIC VALVE
2
14151-00
CARTRIDGE, DUMP VALVE
14353-00
3
PLUG, CAVITY
14350-00
4.4 MAINTENANCE (CONT’D)
2
3
