VAF instruments OILCON MARK 6M, Technical Manual

Page: 86 / 175

85
9.2 WINDOW WASH PUMP
Drawing
0871-1213
shows the window wash pump and will help to visualize the different parts.
NOTE
When the pump is disassembled for repairs, all matched parts should be handled
carefully to avoid damage to lapped or honed surfaces.
CAUTION
Repair work must be carried out by qualified specialist personnel.
Ensure absolute cleanliness. Even the smallest impurities may cause serious damage
to precision machined hydraulic and pneumatic components.
9.2.1 Disassembling the window wash pump
1. Isolate the pump and relieve any pressure from the pump.
2. Disconnecting the 2 water pipe lines and the air supply line.
3. Remove the pump from the skid assembly to a clean and well-lit work place.
9.2.2 Air side maintenance
1. In the eventuality of an air drive malfunction maintenance should be performed on the spool
valve housing (15). Inspect this first and maintenance if necessary, prior to retesting before
further disassembly of the air drive.
2. The spool valve housing (15) is most easily removed by removing the three Allen screws
(26) and carefully lifting it up. Behind the spool valve housing O-rings are located. The spool
(18) and spool valve sleeve (16) can be pushed out by removing the snap ring (23) first.
Spare parts kit
0390-1403
contains all the replacement parts.
9.2.3 Water side maintenance
1. The inlet and outlet couplings are provided with non-return valves. Should a leakage occur
on the water side, replacement of the O-rings (58) should be carried out. Remove inlet
and/or outlet gland completely and replace the O-ring (58) by a new one.
Spare parts kit
0390-1403
contains all the replacement parts.
2. If water is leaking from the wet side to the air side then the following parts should be
replaced. Entrance to the parts will be gained through the hex head screws (37). Remove
the top cap (1). Remove the air cylinder (28). Remove the air piston (30). Place the lower
assembly into a bench vice. Remove the cap nut (44). Now the O-rings (17) (59), glide ring
(47), retainer ring (49) and seal (50) can be replaced.
Spare parts kit
0390-1403
contains all the replacement parts.
9.2.4 Re-assembling the window wash pump
1. Before starting the reassembly operations, all metallic parts are to be washed thoroughly in
solvent.
2. The air piston (30), air cylinder (28) and O-rings should be lubricated on assembly with
lubricant provided in the spare parts kits.
3. Re-insert the air piston (30).
4. Place the air cylinder (28) and the top cap (1) onto lower pump body, taking care of the two
O-rings (4) to sit well and are not “pinched”.
5. Place the pump into the skid assembly and reconnect the water and air service pipes.