95 Merc 115

[Kancel]

I hope someone out there can help me with a strange problem.<br />I have a 95 Astro S18FS with a Merc 115 outboard. It's always run top end @ 6K RPM @ 50 MPH. It's now running @5K RPM @ 40 MPH. I replaced the plugs and wires and ran Sea Foam through it. Even went so far as to fill a gallon jug with gas and a can of Sea Foam and ran it through 3 times. No luck.<br />It runs smooth, no bogging missing or backfiring, just not where it used to be. What's uh the deal? Anybody?<br />Thanks,<br />Mike

 

[studlymandingo]

Re: 95 Merc 115

Have you replaced the prop? Is it waterlogged? Any difference in weight/distribution since you last ran it at 50?

 

[Kancel]

Re: 95 Merc 115

The prop is a Quicksilver Laser II 3 blade, don't know the pitch and the weight and all is SOS from last year.<br />No water in the boat, can a prop get waterlogged?<br />Any other thoughts?<br />Thanks for everyone's help.<br />Mike

 

[north40]

Re: 95 Merc 115

You are fortunate that it is still running as the max recommended rpm is 5250 not 6000. You should change fuel filter and make sure your carb linkage hasn't moved and is still opening up carbs fully.

 

[KCLOST]

Re: 95 Merc 115

Also check compression and spark to rule that out...