2001 Mercury Bigfoot 50HP 4 Stroke midrange missing badly.

[Doindunes]

Hello,

Ok...Here is the prolem. Just last week my boat started to miss badly like I had a bent prop. Replaced the prop as it was due, but I still have the miss (vibration) at about 3,000 to 4,500 RPM according to my tach. It starts and idles fine and is smooth at a slow cruise. Then through midrange it is bad, then high end is fine. I had my marina look it over and they tested the fuel as well as ran aux fuel through the engine. The fuel tested fine (water free) and they even changed the fuel filter. The problen is still there. Now they want to tear off all 4 carbs and rebuild them to the tune of 900-1050 dollars. I am not a boat guy, but it seems that is should be a bit simpler than that! It was fine and even has less than 50 hours on it! The engine is on a 2001 Bennington pontoon 22 footer. Can anyone please help or make a suggestion? Thanks in advance.

Dan

 

[jodyclark8]

Re: 2001 Mercury Bigfoot 50HP 4 Stroke midrange missing badly.

If the carbs are dirty, then they just need to be cleaned. They shouldn't necessarily need to be rebuilt. Its actually quite easy to clean them, just time consuming with four of them. If your just trying to save money, I would try running SeaFoam through your fuel and see if it unplugs your jet. Just try to run it where its roughest and go full throttle every now and again. Sometimes you'll get lucky, but not usually.

 

[Doindunes]

Re: 2001 Mercury Bigfoot 50HP 4 Stroke midrange missing badly.

I wanted to close this thread out. My boat was finally fixed 2 weeks ago by Wilson Marine. It was the carbs that were bad......I did have them rebuilt by the first guy (incorrectly) and chased down the issue with more parts for the next few years. Finally too it to Wilson and paid again for the carbs to be done and it runs like a watch!