Hardi Boss BS 300, Instruction Book

Page: 22 / 60

20
Diaphragms
Remove the diaphragm cover 4. The diaphragm 5 may then be
changed. If fluids have reached the crankcase, re-grease the pump
thoroughly. Check also the drain hole at the bottom of the pump is not
blocked. Reassemble with the following torque setting.
Pump Valve cover Diaphragm Diaphragm
Model Nm cover Nm bolt Nm
1302 45 50 25
1202 70 70 60
1 Nm = 0.74 ft-lb
Changing the ball seat in operating unit
If the main ON/OFF valve does not seal properly
(dripping nozzles when main ON/OFF valve
is closed), the ball and seat should
be checked.
Remove the 2 bolts fixing
the main ON/OFF-pres-
sure valve unit to the
bracket, unscrew the
union nut A and pull the
valve away from the distribution valves.
Check the ball for sharp edges and scratches, and check the ball seat
for cracks and wear - replace if necessary.
Nozzle tubes and fittings
Poor seals are usually caused by;
• missing O-rings or gaskets
• damaged or incorrectly seated O-rings
• dry or deformed O-rings or gaskets
• foreign bodies
A
T199-0001