Idling Rough...Lost Power...3.0 Mercruiser

[scottinvabch]

I have a 2003 Bayliner Capri with a 3.0 Mercruiser I/O. I has run great all summer until this past week...it started idling really rough almost not staying on. I put some fuel system cleaner in the tank and tried to take it out today to run it...and now it will not go above 15 MPH even at full throttle. Any ideas would be greatly appreciated. Thanks!

 

[Don S]

Re: Idling Rough...Lost Power...3.0 Mercruiser

When was the last tuneup? Have you checked for water in the fuel filter or carb?

 

[scottinvabch]

Re: Idling Rough...Lost Power...3.0 Mercruiser

The last tune-up was done before the season started...3 months ago. It does not look like there is any water in the carb and i am not sure exactly where the fuel filter is...is that something easy to change? I have noticed that the flange at the top of the carb stays open...is that normal operation?

 

[Wotknot]

Re: Idling Rough...Lost Power...3.0 Mercruiser

The "flange" or choke plate is supposed to be closed on initial start up. After engine warms up it's supposed to open. Sounds to me like you've either gotten some bad gas on last fill up and/or you've gotten some trash up into your carb.

 

[scottinvabch]

Re: Idling Rough...Lost Power...3.0 Mercruiser

Would bad gas or trash in the carb cause the flange to stay open though? If i manually close the flange and try to start it, it will not start when it is closed.