EN-1320
OPERATION AND INSTALLATION MANUAL
In the case, that the pressure will be adjusted using sealing washers - element 76 - under the cover, then
adding/removing of a washer will reduce/increase the pressure. Washer thickness of 1 mm (0.04 inch)
means pressure change as for the element 73, see above.
NOTE:
Use washers with thickness 1 mm (0.04 inch), 1,5 mm (0.06 inch) and 2 mm (0.08 inch). Maximum two
washers can be under the cover.
Screw the cover 72 (with pressing the spring) manually to the relief valve body 71. Then hold the body 71
with a suitable wrench and tighten with other wrench the cover 72.
CAUTION:
DO NOT TIGHTEN THE RELIEF VALVE BODY TOO MUCH. OVERTIGHTENING THE RELIEF VALVE
BODY CAN CAUSE SLEEVE VALVE STICKING [77, FIG. 12-35]. A LOOSE RELIEF VALVE BODY
WILL RESULT IN AN OIL LEAK.
Secure the relief valve with lock wire.
Purge air from the system at engine ground test.
(4) Remedy for relief valve leakage
Relief valve leakage can be caused by loosen relief valve cover or defective sealing.
Remove lock wire from cover [72, fig. 12-35]. Hold the relief valve body [71, fig. 12-35] using a suitable
wrench then tighten the cover.
Secure the relief valve with lock wire, use standard procedure.
If defective sealing is the cause, remove lock wire, hold the relief valve body 71 to fix it and remove the
cover 72.
NOTE:
Be careful when removing the cover to don’t loose washers 73 and to keep pin 74 on the spring 75!
Defective sealing washer – element 76 – remove and measure total thickness with accuracy 0,1 mm
(0.004 inch). Prepare new sealing with the same thickness. Use maximum two washers.
Split the new sealing washers onto the cover 72. Verify, that the pin 74 is at the spring 75 and original
washers 73 are installed.
Hold the relief valve body 71 with a suitable wrench and screw the cover 72 with the washers 76 and
tighten with other suitable wrench, see above.
Secure the relief valve with lock wire.
(5) Remedy for turning screw leakage
Remove lock wire from the turning screw 78 - figure 12-36 - and from the both tube cap nuts.
Remove the tube 86 (to the feathering pump LUN7840-8). Remove the tube 87 (to the feathering valve
LUN7880-8).
NOTE:
Before removing the tube it is necessary to loosen the nuts at each end of the tube. If it is not
necessary, don’t remove the nut 59 with the ball 60 from the turning screw 78.
Remove the turning screw 78 together with parts 45, 46, 44, 59, 60, 88 and remove defective sealing rings
89. Be careful for the ball 92.
61-10-20
PROPELLER CONTROL SYSTEM
(Installation With Jihostroj LUN-Series Governor)
Page 12-39
2017-10-06
