Hello
Recently been working on a 1991 Bayliner Capri with a 4.3 Mercruiser engine. Boat sat for several years and was difficult to start and idled very rough. I drained the fuel tank, replaced fuel/water separator filter, soaked carb with seafoam spray and treated fuel with seafoam, filled with non-ethanol gas and was able to get engine to idle well and come up to temp on the muffs and in the lake.
However, on the lake, the boat will quickly come up onto plane with about 3/4 throttle and run great for a few minutes. Then after a few minutes it begins to bog down. Sometimes it will then regain power but quickly bog again (sometimes several times). Otherwise engine typically bogs to the point of stalling. This also happens if throttle is pushed past the 3/4 point and it will cause it to bog out quickly.
Engine typically starts right back up fine and is able to drive back to dock at low speeds and sounds fine. Also, decided to anchor out and let the boat sit for about an hour. After the hour, boat seemed to have full power again for about 5 minutes (again not past 3/4 throttle), but then exhibited the same bogging.
From other posts it seems the list of possible causes is endless between plugs, wires, distributor, fuel pump, carb, etc. Looking for some insight on where to start rather than just throwing parts at it.
Thanks in advance!
Recently been working on a 1991 Bayliner Capri with a 4.3 Mercruiser engine. Boat sat for several years and was difficult to start and idled very rough. I drained the fuel tank, replaced fuel/water separator filter, soaked carb with seafoam spray and treated fuel with seafoam, filled with non-ethanol gas and was able to get engine to idle well and come up to temp on the muffs and in the lake.
However, on the lake, the boat will quickly come up onto plane with about 3/4 throttle and run great for a few minutes. Then after a few minutes it begins to bog down. Sometimes it will then regain power but quickly bog again (sometimes several times). Otherwise engine typically bogs to the point of stalling. This also happens if throttle is pushed past the 3/4 point and it will cause it to bog out quickly.
Engine typically starts right back up fine and is able to drive back to dock at low speeds and sounds fine. Also, decided to anchor out and let the boat sit for about an hour. After the hour, boat seemed to have full power again for about 5 minutes (again not past 3/4 throttle), but then exhibited the same bogging.
From other posts it seems the list of possible causes is endless between plugs, wires, distributor, fuel pump, carb, etc. Looking for some insight on where to start rather than just throwing parts at it.
Thanks in advance!