06 40 4 stroke running rough

[boc9]

I have a 2006 40 hp 4 stroke bought new in 2007 fairly new motor.
It starts fine & idles fine, mid range running rough , top end seems fine.
This boat is used most every weekend , no water in gas , clean filter, & new plugs. The problem just started a few weeks ago but getting worse.
Thanks for any help !! Boc

 

[boc9]

Re: 06 40 4 stroke running rough

I have a 2006 40 hp 4 stroke bought new in 2007 fairly new motor.
It starts fine & idles fine, mid range running rough , top end seems fine.
This boat is used most every weekend , no water in gas , clean filter, & new plugs. The problem just started a few weeks ago but getting worse.
Thanks for any help !! Boc

motor also popping thru exhast... I pulled the spark plugs , the porcelian is clean on one side and black on the other ??? How about some help !! Boc

 

[Jeep Man]

Re: 06 40 4 stroke running rough

I have an '02 60 hp and the guy I bought it from ( Merc mechanic ) said he had already installed a new fuel pump because the older ones were under recall because of an internal problem whereby they cause rough operation at mid throttle. Might be what's wrong with yours.

 

[boc9]

Re: 06 40 4 stroke running rough

Thanks for input jeep man ! I tore carbs down and cleand them, i found some trash , but not much. motor is running alot better , not perfect. Boc

 

[coolguy147]

Re: 06 40 4 stroke running rough

think this motor is efi

 

[boc9]

Re: 06 40 4 stroke running rough

3 carbs