Uneven engine speeds.

[Doc O Rock]

Last fall, the last day before the boat went to sleep, I noticed that to get the engines to sync on the meter, I had to have the throttles uneven. Never had that problem before. I'm thinking fuel filters. Any thoughts?

 

[fwebster]

Perhaps, but just as likely an injector failure, a plug wire breaking down or one or more fouled plugs.

 

[Doc O Rock]

Plugs and wires are 2 seasons old, the injector is a question mark. It's a good thing my mechanic owes me.

 

[MickT]

Or worn throttle cables, or something slowly going out of adjustment...

 

[TNT8808]

While these all sound like good ideas to check out, I had what sounds like a very similar situation at the beginning of last year with my previous boat (2001 410DA). I chased it for about a month with our marina mechanics, and even had Michigan CAT on the boat and they finally determined it had nothing to do with the engines or electrical systems and was in fact a bad tachometer. Long story short, I replaced the factory tachs with Aetna digital tachs and all was good the rest of the summer (70 hours) and sold the boat in early fall.

 

[370Dancer]

Perhaps, but just as likely an injector failure, a plug wire breaking down or one or more fouled plugs.

+1 Mine was fouled injectors, and a couple of cracked injector connector blocks a while back, causing an intermittent loss of RPM.