Pumps

Of core snot; that's why pumps are useless.

its a magic trick. they don't

Especially if the drive shaft is not being driven. What's the nature of your doubt?

Install a pressure gauge and see what it tells you. If you don't know what a pressure gauge is follow this procedure:

Place finger over discharge of pump for up to 1/2" npt discharge. Palm of hand for 3/4"--->2" npt discharge (if you have big hands then up to 3"). Caution- do not stick these digits or extremities inside the outlet!). Turn pump on. If hand or finger is being repulsed from the discharge of the pump it is working. No pressure on finger or hand then no pressure from pump.

If the pump was last used for hazardous materials or other things detrimental to any part of the human body, DO NOT DO THIS PROCEDURE!!!!! Go back to pressure gauge installation procedure. Suggest you start and finish with the pressure gauge.

I have a very big doubt too. You didn't say but it could be a vacuum pump!

Good Luck, Old Salt

Well, if it isn't producing pressure, and a pressure gauge downstream will reveal this one way or another, switch the bloody thing off and fix it!

Do you know what a pump curve is?

What is a pump and how does it work

I give up.

I think OP 'go bye bye'

Back to basic question,

if you look in to fluid mechanic basic, pump does not give the pressure it gives the flow.....and they says restriction to flow gives pressure....that simple.

in case of rot-dynamic pumps you get pressure up to certain value then surge comes in picture, but it positive displacement you can reach up to infinite bar until your pump cracks.