Has anyone changed a 2008 or newer waverunner spark plugs. Is there someplace that shows you how, other then a parts picture? I am mechanically inclined but do not want to break any seals or compound my problem.
It looks like you have to get to them by removing the valve cover with 4 hex screws, is this right?

We are having a problem where the max speed went from 65 to 35. Still has rpms to 7-8k idles fine but no hole shot or top speed.
Have been running 87 octane but recently have put in 89 and some injector cleaner with no help. It ran great the first 2 days but then started to go from 50 to 35 back to 50 and then 35 and now will not get past 35 ever. No obstructions in the impeller either.

Will take all suggestions. This is the second year out and always kept in the garage in winter, but still winterized.

also it is not in safety mode or L. but it does act like it is.

Michael

Might need to get this
http://www.goldeagle.com/brands/stabil/products.aspx#marine_formula


I've worked on older waverunners when I had them and there was never anything I had to worry about when changing plugs I not sure if they have changed that on the newer ones but I don't see why they would.

Thank you we will try this once we get the spark plugs checked. But i really want to check and or change them myself.

It was fairly easy . Of course just be careful! I suggest ask other waverunner owners & hear of their experiences and go for it. It's worth trying, and the next time you'll feel good about changing them. Took about an hour or so, including changing the oil & oil filter for me with an assistant.

Michael,
I'm having the exact same problem you described with my 2008. Did you end up changing the plugs? Did that solve the problem? What were the basic steps to changing the plugs?
Thanks.

Regarding spark plug changing, I found the following tech tips from a dealer down under. Scroll down and there are images with instructions on changing 4-stroke FX plugs.

http://www.fullwavemarine.com/TIPS%20FOR%20YOUR%20YAMAHA%20PWC.html