Motor?

[jeremyt]

After having my boat at the mechanic for five weeks with no service I picked it up. My problem was that the boat is sluggish, it will only push about 5k rpms and it seems that I have to push the throttle down a lot further to get it spun up at all. I got it home and changed the plugs, fuel filter and the fuel water separator. I had about half a tank of fresh fuel left so I burnt that out, filled back up added some startron and took her out. I am still getting the same performance out of the motor.

A friend told me it could take a tank or two before it starts running right. Is that normal? Another guy told me that it could be the coils or stator, but I figured I would start with the more inexpensive stuff that I could do myself before I moved on. Any suggestions? The motor is a 2006 merc 4 stroke.

[Way2slow]

It's not going to be very practical to start just swapping parts. They are very expensive and you can go through a lot of other peoples thoughts and still not get it running right.

Have you check the simple stuff like making sure the throttle is opening all the way and the timing is advancing properly.

When you start getting to indepth trouble shooting, you will need the computer software and connector cable. Very good change it will tell you what the problem is. A misfiring cylinder drops about 1,000 rpm. I've never worked on a four stroke but I know a two stroke can be down a cylinder and you may not feel it, just the drop in performance

[ww2farmer]

Same year as mine 2006, Merc 4 stroke. Sounds like the same problems I had last year. Have you drained the float bowl's on your carb(s)?? Also the startron is good for preventing fuel problems.............cure them, it will not. Once you have problems, your better off using a dose of seafoam mixed with the startron, and then just the startron after you get it "cured". I did every thing you described too, changed plugs, fuel filter, changed all the rubber fuel lines, drained the old gas and replaced with new. But it wasn't untill I drained the float bowl, and ran about 1/4 tank of the seafoam startron mix through it that it cleared up. Don't skimp on the seafoam either, use the whole bottle, and then after you run that tank through, change the fuel filter again.

[jeremyt]

My motor is efi, I did find something new today. I primed the bulb and heard a sucking sound coming from the fitting where the gas line hooks to the tank. I cut an inch off the hose and refastened it and no longer had that issue and the ball tightened right up. Could that cause the problems I am having?

[Fishing Rhino]

Yes it could. Any loose fitting/connection between the tank and the motor will allow air to be sucked in.