BLACKMER 111-F01, Installation, Operation And Maintenance Instructions

111-F00     Page 6/16 

OPERATION 

FLUSHING THE PUMP 

NOTICE: 

If flushing fluid is to be left in the pump for an extended 
time, it must be a lubricating, non-corrosive fluid.  If a 
corrosive or non-lubricating fluid is used, it must be 
flushed from the pump immediately. 

 
To flush the pump, run the pump with the discharge valve 
open and the intake valve closed.  Bleed air into the pump 
through the intake gauge plug hole or through a larger 
auxiliary fitting in the intake piping.  Pump air for 30 second 
intervals to clean out most of the pumpage. 

1.  Run a system compatible flushing fluid through the pump 

for one minute to clear out the remainder of the original 
pumpage.  The valve in the discharge line should be 
restricted to build up 10 psi (0.7 bar) to force flushing 
liquid through the bearing seal chamber. 

2.  To remove the flushing fluid, follow step 1 above. 

3.  After flushing the pump some residual fluid will remain in 

the pump and piping. 

4.  Properly dispose of all waste fluids in accordance with 

the appropriate codes and regulations. 

OPTIONAL PUMP RELIEF VALVE: 

Hazardous pressure 

can cause personal 

injury or property 

damage

An external bypass valve and/or an 
internal relief valve MUST be installed in 
the system to protect the pump from 
excessive pressure.

Hazardous pressure 

can cause personal 

injury or property 

damage

.

Incorrect bypass valve or internal relief 
valve settings can cause pump 
component failure, personal injury, and 
property damage. 

1.  Blackmer ProVane pumps may or may not be fitted with 

an internal relief valve.  If an internal relief valve is not 
supplied, an external bypass valve must be used. 

2.  The pump’s internal relief valve is designed to protect 

only the pump from excessive pressure and must not be 
used as a system pressure control valve. 

3.  Internal bypassing of liquid elevates liquid temperature.  

Internal relief valve should only be used for brief periods 
and for differential pressures below 125 psi.  For 
extended periods, an external bypass returned to source 
must be used. 

4.  The pump relief valve cap must be on the inlet side of the 

pump.  If pump relief valve is installed improperly, it will 
not operate and a component failure may result.  See 
Figures 4 and 5. 

Fig 4 Right Hand Orientation 

Fig 5 Left Hand Orientation