Low Pressure/low volume

Terry,
I am having a problem with my well and am out of ideas. Please point me in the right direction. My well was working properly and then went dead. The pressure switch was really rusty so I thought that was the problem and replaced it (a 20/40 version) to no avail. Upon further inspection I found that my electrical feed had one leg of the 230 volts burnt into. I repaired this and the pump came on but I only have about half the flow/pressure as before the problem. I replaced the airtank (19 gallon) with a new one as the bladder appeared to be ruptured on the old unit. It came precharged to 40 pounds and I decreased it to 18 pounds before applying any water into the tank. Turned the pump back on and the same problem. At this point I pulled the pump (120 feet of depth) and upon inspection of the wires I discovered they were exposed where the wire had rubbed the side of the casing when the pump would cycle. I spliced these and put everything back together. Still have the same problem. It's a Gould 2 wire 3/4 HP submersible pump. If it helps the model number is 2443070117. There is no control box. The pump is controled solely by the pressure switch. There isn't a pressure gauge installed in the pit so I can't tell you any readings. I have the ability to install a gauge in the line just as it come out of the casing which will have it about 4 feet from the airtank without doing any repiping. Is this location okay or must I put the gauge somewhere else? Any help will be greatly appreciated.

Thanks,
Emmett

a quick fix gauge just pop it on to the air inlet valve on the pressure tank. this will tell you the line pressure. dissconect the pipe work and run the pump into a bucket and time it how long it take to fill 3 gallons divide this by 3600 x 3 is gph of pump. work out pwl and this will tell you if pump is on par with what it should be .

cheers max