O.K. guys. I've searched the posts, but can't find an old post pertaining to my particular problem. I have a confusing issue that has me pulling my hair out. I bought a 1986 Stratos bass boat with a Yamaha ProV 150 a couple of years ago. It seemed to have run well with muffs, but looked like a monkey had a hand in wiring it. I rewired most of the boat as time permitted, and roughly a year later, I took it to the lake. I warmed it up at the house on muffs so I knew it would start easily at the ramp. When I got to the ramp, I started the engine in the water. It sputtered, and tried to die. Water was coming out the top of the leg right below the powerhead, so I knew something was wrong. I tore the lower unit apart,to replace seals, and discovered a seal in the housing was MISSING. So I installed a new one. While I was in there, I replaced the impeller, housing, etc. A couple of months ago, I tried to test it out again, but it wouldn't run. I pulled all 3 carbs off, and went completely through them. Thoroughly cleaning them, blowing compressed air through all the passages, etc. I drained and cleaned the tank, replaced the filter, the pickup tube, and all the fuel lines, primer bulb and spark plugs are new. It ran awesome on the muffs. I took it to the lake today, and it fired right off. Then it sputtered and died. It would not restart in the water. I pulled it back up the ramp, checked spark on all 6 cylinders, and it fired right off again. When I backed it back into the water, it started, ran about 5 seconds then died and wouldn't restart. I know fuel system is always the first to get blamed, but at this point I'm wondering if something is amiss in the lower unit. Maybe too much back pressure in the exhaust? I'm fairly certain the carbs are clean and good to go. I'm truly at a loss right now. I'm about at the end of my rope. I JUST WANT TO GO FISHING!!! PLEASE HELP!!!
