I have an old jacuzzi 5rm2 1/2hp pump assembly(now manufactured by franklin pump,their part number is jrm05c1-c). My problem is with water pressure,or lack of it. When I prime my 1-3/4" shallow well(23ft.),the pump starts to build pressure,rises to 25-30lbs(slower than normal),but continues to rise(now very slowly),to 48lbs(cut-out setting). Eventually it turns off. Pressure will stay constant at 48lbs for at least an hour,so no leaks are present. My problem starts when you open a faucet. I have a faucet on the pumphouse,so I can see what is happening. The water will flow full force for about a minute or so,then the pressure starts to drop,at 28lbs the pump turns on(cut-in setting). About 10-20 seconds after pump kicks on,the pressure drops to about 5lbs and will not build up until I shut the faucet. Once faucet is closed the system goes thru the same cycle as before. One forum said the jet might be clogged,causing the slow pressure problem. I took out the plastic plug but didn't see a jet inside. Franklin pump list a jet,part number 18-1278-03-r,for this pump. Is anybody familiar with this pump and jet? Does anyone have a manual or diagram or picture of jet placement in this pump?

richard j ryan jr