9-58
PTT gear pump
0
1
2
3
4
5
6
7
8
9
10
A
A. Up-relief valve
B. Down-relief valve
2. Remove the bracket “1” and O-rings “2”
and “3”.
3. Remove the gear housing “1”, and then
remove the drive gear “2”, driven gear
“3”, balls “4”, and pins “5”.
4. Remove the valve seat “1” and O-ring “2”.
Checking the gear pump
1. Check the drive gear and driven gear.
Replace the gear pump assembly if dam-
aged or worn.
2. Check the up-relief valve and down-relief
valve. Clean if there is dirt or residue.
Checking the gear pump housing
1. Check the PTT body. Replace if corroded
or cracked.
Checking the valve seal
1. Check the main valves and the shuttle
piston. Replace if damaged.
2. Check the manual valve, manual valve
seat, adapter, and springs. Replace if
damaged.
Checking the filter
1. Check the filters. Clean if there is dirt or
residue.
AB
1
2
a
b
21
3
4
5
6
7
8
1
2
3
1
2
3
4
5
5
1
2