Actual data taken on 13-B Water pump at 3 different rpm values.  Driven with
a 3450 rpm table-saw motor with 3 different pulley sizes (2-5/8" , 4", 6")
driving the 3.7" water pump pulley. No evidence of belt slippage or motor
strain, however I did not use an electronic tach for the rpm measurements,
just calculations from the motor rating.

Pressure is measured at the outlet of the pump, before going back into the
barrel through ~ 6 feet of 1-1/4" corrugated sump pump hose.

Pump is supplied from barrel with ~20 feet of 1-1/4" corrugated sump pump
hose.

The barrel was positioned to provide neutral head in a static position,
however at the higher flow rates, there is clearly pressure drop in the
supply and discharge hose that helps restrict flow.

Bill Schertz

"Schertz, William W." wrote:

One other point, looking at the pressure capability of the pump, with a
sudden increase in rpm, you could easily cause liquid to be expelled past
the radiator cap if it is on the pump outlet side.  This is the reason mine
is located on the low pressure side of the pump.

Bill Schertz

There is also a pressure drop in the block so if it is on the outlet
side beyond the block it should be OK.

Next step is measure all the pressure drops in an actual system.

Paul Lamar

Great work Bill.

How did you measure the water flow.
I will do some test on the self contained pump that I posted.
Regards Don

The usual way is a stop watch and a five gallon bucket.
Paul Lamar

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