I have a 2003 340 Sundancer wit...

[Vermont_Sundanc]

I have a 2003 340 Sundancer wit 8.1 Mercs. It has run flawlessly with the exception of the starboard engine losing power/RPM while cruising/on plane. It drops 300 rpm +/-.

When this happens, I give it more throttle to stay synced with the port engine and after a few minutes, the starboard engine ramps up rpm and I'll readjust the throttle to match rpm again.

This happens sporadically. Any help is appreciated. Thanks.

[340_Sundancer]

my 04 did the same thing. I found a loose plug wire on the Starboard engine outboard cylinder bank. It wasn't pushed all the way on the spark plug.

[Vermont_Sundanc]

Thanks for the suggestion. I'll check the connections today.

[Flame]

I had the same issue at about 150 hrs on the engines; the starboard needing more throttle than the port to sync the RPMs. I replaced all the plugs at the suggestion of our Club's Marine Service Center. They said it is common for the 8.1s to eat the iridium plugs..

[Vermont_Sundanc]

Excellent info. Thanks Flame.