I have a 1977 Johnson 55hp outboard (55EL77D) that fights to start and run at lower RPM's while on the lake. When it gets going at high RPM it runs like brand new. It refuses to start after it is warmed up and dies when I put it into gear. It idles rough and also slowly cruises rough. This is the 3rd fuel pump I have put on this motor. The fuel pump put out a continuous 3 psi no matter the engine speed the other day when I got the primer bulb to a firm position. I took it out on the lake and everything just went to heck. It didn't want to start and when it did every time I would put it into gear it would die. I would prime it until the bulb seemed firm, start it and then die. When I did get it running it wanted to die but would take off when I choked it for a quick second. I had to use the thumb wheel on the throttle cable to increase the RPM's to a minimum of 2400 then slam it into gear, choke it and then pray. I rebuilt the carbs last year which included soaking both of them. The jets are set so no adjusting them. Cylinder compression is 150 psi on both. Plugs have a nice tan look so no fouling or flooding. I have shortened the fuel hose so the bulb is as close as possible to the tanks. The tanks are Attwood 6 gallon poly. Maximum spark gap is about 1/2 inch and strong. I'm about 2 seconds from going against USCG recommendations and put an electric fuel pump on it. Any help would be appreciated.