2008 Mercruiser 3.0L needs a carb cleaning

[TBarCYa]

I believe that the fuel that was in my carb from the end of last season has gone bad and gummed things up so I'm planning to disassemble and clean the carb. The question is, do all of the gaskets in this carb need to be replaced or are they good gaskets that can survive a disassembly and still be usable? The engine has about 20hrs on it and a couple quick searches have not revealed a gasket kit.

When I first took it out on Wednesday it ran great for the first couple minutes then it wouldn't rev past 4000rpm. If I set the throttle and let it run, after a minute it would accelerate like crazy for a minute then go back to running bad and continue this cycle the whole time it was moving. I'm going to pull the plugs but I suspect that they're going to tell me that it's running lean.

Any help is greatly appreciated.

Thanks.

 

[Bondo]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

Ayuh,...

I'd start by changing the Fuel Filters...
If that don't Fix it,.. Buy a Carb Kit...

 

[ziggy]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

so did ya store it with stabil in it?

i know nothing of your brand new engine. but i personally wouldn't suspect the carb. right off the get go.

since it's a new boat, is it under warrentee?

did you check out the won't reach wot thread in the adults only sticky at the very top of the i/o forum?

lots of possible causes of not reaching wot other than needing a carb rebuild..

any gasket in a carb is not reusable best i know, at least not if you want to be successful at a carb rebuild.....

 

[TBarCYa]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

For some reason there is no water separating fuel filter yet and from what I remember of looking at it, I don't recall seeing a filter other than the one I know is in the fuel inlet of the carb. I wasn't looking for a filter tho so I may have simply overlooked it.

Last season ended and my hose froze before I had a chance to winterize the boat so I added stabil to the tank and fogging oil to the cylinders but was unable to run the engine to get the stabil into the carb or do a proper fogging. This is the main reason I'm thinking gummed up carb.

It is still under warranty but if the issue is in fact a gummed up carb it wouldn't be covered anyway.

 

[JustJason]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

a 3.0L doesn't come standard with a fuel/water seperator.

Before you go tearing into the carb, get a small outboard fuel tank with fresh gas and hook it up to the fuel pump.

Stabil or no stabil it's been a long cold winter up here in new england. Running off an outboard tank will tell you if you have spoiled fuel or not.

 

[TBarCYa]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

The tank was little better than half full when it was stored (mistake #2) and I topped it off before heading out. I'll try an auxiliary tank and if it turns out that the gas is bad, I'll use it in the lawn mower. That thing will run on anything that smells like gas!

 

[Bondo]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

For some reason there is no water separating fuel filter yet and from what I remember of looking at it, I don't recall seeing a filter other than the one I know is in the fuel inlet of the carb. I wasn't looking for a filter tho so I may have simply overlooked it.

Ayuh,... There should be another 1 inside the Fuelpump...

 

[fat fanny]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

When you said your hose froze before you got a chance to winterize it. I sure hope you drained the block and manifold before or after you fogged it.

 

[TBarCYa]

Re: 2008 Mercruiser 3.0L needs a carb cleaning

I didn't get to fog it because I couldn't run it without water. The block and manifold were drained with the built-in drain hoses after the last time out and the drain plugs removed when I finally put it up for the winter. I sprayed the fogging oil in the carb and pulled the plugs and sprayed it in the cylinders too.

As it turns out, when I pulled the plugs expecting to see that it had been running lean, I found that all 4 looked perfect except for the insulator being badly cracked on one. Since this is likely the cause of the poor running, I'm going to hold off on tearing into the fuel system until I get a chance to run it with new plugs.