ok i know i posted before about this but the post wasnt going anywhere. So i got a diagram and some voltage readings hope this helps

i have a/c on my boat but the compressor wont run. The charge is good, im thinking either the a/c compressor is bad, something with the capacitor, or in the circuit board. Anyways its a 115v ac system.
The purple wire going into the compressor from the circuit board has 115v, there is 115v on the orange wire coming from pin S (compressor), pin c 115v (compressor), pin R 1.2v (compressor). There is also 1.2v on the white wire coming from the capacitor which has 115v going into it.
Alright NOW with the white wire removed from pin R at the compressor the compressor shows 115v on that pin. With both white wires removed from the circuit board at the compressor run it shows a output of .5v
Im very new to 115v AC current compaired to 12v DC. If you need more info ill try to fill you in. But this is what i got from testing last night. Below is a wiring diagram

Not for nothing but....I know you have been messing with this for quite some time. Have you tried some kind of HVAC forum? I know it is in a boat, but you might find better advice from those guys.

Caps can and do go bad sometimes, it might be something to try if you can get a replacement for cheap enough, just know that if you go this way, most supply houses will not take it back.

Ya, i found a hvac forum and they have me on a path. i need to check one thing out tomorrow and get the part number off the cap.
Thanks for the help

Are all your voltage readings taken to ground???.....a voltage reading taken to ground doesnt tell you much in an AC circuit.... all readings in a 115 v circuit are to be taken to neutral (white)....1.5 or .5v is taken as zero.....what do you get when you put your meter across purple and white on the terminal strip on the board???.....im guessing zero.....when your trying to get the unit to start does the comp get hot????.....typically small units like this have problems with the T Stat.....do you know how the T stat works??....is it wall mounted or is there some sort of a dial on the unit??....either way put a jumper wire across the stat terminals and see if it fires.....D

did you check the power to the fresh water cooling pump? i believe it goes between the compressor circuit so it can pump water to cool the condensor..their may be some kind of water pressure circuit involved as well..If it dont see water pressure going to the water cooled condensor it may not turn on the compressor..