Gregson-Clark V-50B-SA - Troubleshooting; Diaphragm Pumps

VSS 10-12
14
TROUBLESHOOTING
Problem
Possible cause
Solution
Low or no pressure or
Valve in suction strainer closed
Verify cup alignment with valve stem
Pump does not prime
See page 12
Plugged strainer
Clean screen
Plugged suction hose
Clear obstruction
- Check top of strainer for debris
Faulty or missing o-rings in Strainer
Replace o-rings
Assembly or pump Inlet Elbow Barb
Air leak in pump suction hose
Check hoses and fittings for leaks
Stuck or worn pressure relief valve on
Repair or replace relief valve
regulator
Low liquid level in tank
Refill tank
Improperly seated check valve(s) in
Clean or replace check valve
pump head
Fluctuating pressure
Pulsation dampener pressure incorrect
Adjust pulsation dampener pressure
(Excessive pulsation
-Should be at 20% of operating pressure
of Hoses)
Pump not purged of air
Run pump with regulator in the bypass
position to purge air
Defective regulator
Repair or replace regulator
Diaphragm Pumps
Pump oil has milky color
Ruptured diaphragm(s) in pump
Repair as necessary
Pump oil level low
Table 1