Fuel separation and water

I replaced the motor on my 2005 Amberjack recently. Everything seemed to be going great. While on the hose, the motor started fast and ran very well. I was finally able to take the boat out to the lake and this is where I found problems. The motor ran good at idle speed and handled well. It was when I increased the throttle that I ran into problems. Anything over idle speed and the boat would lose power and start to shake really bad. I pulled the boat back out and again, at the house, I could find no problems. While on the hose everything was normal. The motor would rev up without a problem and when placed in gear, the drive was fine. I put the boat back in the lake and it idled fine but upon increasing power, it would drop RPMs and start to shake. I brought the boat back home and started to scratch my head. Since the motor is a closed cooling system, I knew the problem had nothing to do with lake water. I then decided to check the fuel. I put my fuel pressure gauge on the fuel rail and everything was normal. I watched for leak down but did not see any. I then started the motor and after a tiny dip in pressure it came back to normal. I revved the motor and it had small dips in pressure but recovered quickly. So this ruled out fuel pump and pressure problems. I then went to bleed off the pressure to remove the pressure gauge. I had a small Ball jar and released the pressure into the jar. I capped it and placed it on the deck and put everything back to normal. As I climbed out of the engine compartment, I picked up the jar and noticed a small separation in the little amount of fuel in the jar. I went back down in the engine compartment and reconnected the pressure gauge. I built up fuel pressure several times and relieved it into the jar. Sure enough I had a small phase separation, not much but it was there. My fuel gauge showed about 30 gallons of fuel but it was fresh and non ethanol fuel. My guess is, I still had bad fuel left in my tank. I found a place to put the boat on about a 15 degree incline and I disconnected the fuel line and connected an electric fuel pump to the line. I then was able to pump out almost 1 1/2 gallons of bad fuel. As I pumped, I did not see a separation until I started on the second gallon. I then pumped until I got a full gallon without a separation. A friend of mine recommended a product call K100. I ordered it and I am waiting for it to come in before taking the boat out again but I think that the separation of fuel was my problem.

 

Sorry it was so long but just wanted to explain how I got from A to Z.