I have a 1990 Wellcraft 3300 coastal, it was updated in 2000 with 7.4 Merc Bluewater Mpi engines. I purchased the boat in Aug. 2007 with approx. 250 hours on each engine. The Boat had been sitting for approx. 6 months when I purchased it ( Possibly Longer ) . Now The problem: When I was about to purchase the boat the seller had the marina get it ready for the survey, apparently the fuel was separated by this time (ethanol ) the marina had put new fuel water separators on each engine. The boat ran but never that well during the engine tests on open water never really reaching full power. The survey company checked the engines for cylinder pressure and determined that the engines were good and that it was a fuel problem related to ethanol fuel separation. The boat was run every weekend up until October 2007 with one or the other engine stalling at idle every once in a while when coming into the dock. The engines always started back up quickly but never had full power. The fuel was treated and the filters were replaced often during those few months. The Main tanks were never cleaned at that time. I kept the boat in the Chesapeake city area until February 2008 until I built a custom trailer to hall her to Pennsylvania. In May of 2008 while sitting on her trailer in PA at our shop the fuel separators were changed again with the same filters that were on the boat when I took delivery. The boat engines were started, both engines started right up and ran off of a 20 gallon axillary fuel tank until the main tanks could be addressed, they would run for a while and shut down when the throttle input was increased, but would start again.. A fuel pressure gage was connected to the upper port behind the water pump area on top of the engines. The pressure was rising to 80 to 90 psi on both engines from what I remember and then the engine would cut out, My Dad was an automotive tech and knew a bit about fuel injection however he was at the end of his career when it was new thing, lol.. We had gotten some indication that the computer was shutting down the engine because of the excessive pressure; there is a fuel cooler on the lower right side of each engine with a pressure relief valve and a return line back to the separator mount. The relief valve was changed on the port engine and the line was removed and checked for blockage. The problem was still there. Now the bad news: I caught my wife cheating about a week later and the boat was dropped like a hot potato, lol. Well it?s now June 2011 and this weekend I opened the deck up again. Thank god for fuel problems or what she thought was garbage because I still have the boat. Well now with new gas same filters she turns over but will not run or start off of the auxiliary fuel system. A spearing shot of starting fluid in the intake brings both engines to life for a second this ruled out any other engine problems like spark or timing. I put an electric fuel pump at the auxiliary tank to help prime the system however I don?t think she?s getting fuel to the rail or injectors and that?s the new problem.
Multiple problems here any input will be helpful. I am in the middle of PA not really near any marine dealers that want to make house calls; the boat is 13 feet wide and can?t be easily haled without a tractor and permits.
I?m only left with the limited mechanical knowledge that my dad taught me over the years that we spent working on weekend projects.
Questions:
Is there any procedures for bleeding the air from the fuel system?
Is it possible that the marina put the incorrect fuel water separators on, not letting the fuel return?
Are the injectors bad?
What are the proper filter #s for this engine and its separator mount?
Multiple problems here any input will be helpful. I am in the middle of PA not really near any marine dealers that want to make house calls; the boat is 13 feet wide and can?t be easily haled without a tractor and permits.
I?m only left with the limited mechanical knowledge that my dad taught me over the years that we spent working on weekend projects.
Questions:
Is there any procedures for bleeding the air from the fuel system?
Is it possible that the marina put the incorrect fuel water separators on, not letting the fuel return?
Are the injectors bad?
What are the proper filter #s for this engine and its separator mount?