How To Replace The Diaphragms And Change Oil - Bertolini GIARDINAGGIO Serie Manual De Uso Y Mantenimiento

6.4

How to replace the diaphragms and change oil

The pumped liquid could damage the mechanical components if one or more of the
diaphragms failed.
The diaphragm failure is denoted by:
The whitish colour of the oil (water in the oil)
–
Excessive oil consumption
–
Sudden disappearance of the oil from the filler, thus from inside the pump.
–
The diaphragm failure is frequently caused by:
Throttling in the suction circuit (see paragraph "SUCTION HEAD AND NEGATIVE
–
INLET PRESSURE")
Use of extremely aggressive chemicals.
–
WARNING!
All the nuts and bolts unscrewed in order to service the pump must be retightened
to the required torque value with the proper torque wrench. Consult the charts in the
spare parts catalogue for the required driving torque values.
Replace the diaphragms and the oil as described below:
1.
Disassemble the pump heads one by one.
2. Use a setscrew wrench to remove the diaphragm bolt and plate.
3.
Remove the diaphragm.
4. Remove the piston sleeves, if necessary.
5. Allow all the oil in the pump to drain out.
6. Flush out the inside with diesel oil, depending on the state of wear
7.
Fit the new diaphragms on the piston at half of its stroke. Insert the diaphragm
edges into the groove along the circumference around the piston sleeves.
8. Use the proper wrench to tighten the bolt to the following torque values:
M6x1 = 5N/m M8x1.25 = 12 N/m
9. Fit the heads back in place and tighten the corresponding bolts.
10. Fill the pump with oil and, at the same time, turn the shaft manually.
After this operation, proceed with the installation and follow the instructions of the
paragraph "PRELIMINARY OPERATIONS".
M10x1.25 = 25N/m
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