Loss of power...possible plug problem?

[itguy]

Hi - Well, it was a beautiful day so I was able to take my boat out for the second time. My goal was to see what RPM at WOT I'm at to make sure the correct prop is on the boat.

The engine started fine, acceleration was what I remembered from the first time but the RPM's were at 4600 and I could only get up to 50 with my wife and I. The first time I took the boat out (2 weeks ago) I had four adults and we hit 59 (GPS) so I guess something is wrong

I did fill it up with gas for the first time and made sure the correct amount of oil was added. I also added one can of Seafoam since I've read many good things about it.

Oh yeah, it's a 2001 150 XR6 on a 2002 Procraft 180 combo. The previous owner supplied a report from his dealer and everything checked out. The plugs, oil, fuel filter, batteries, impeller, etc... were all replaced last May.

I purchased a manual for the motor but it hasn't arrived yet. I don't know much about outboard motors but I felt I could handle average maintenance tasks.

Please see pics of the plugs and let me know what you think. I pulled all six and they all appeared the same.

Thanks!

 

[CharlieB]

Re: Loss of power...possible plug problem?

How much old fuel was still in the tank when you filled up?

The plugs are a good color but have the look of old fuel, how does the fuel smell?

The Z on the plug indicates a precious metal, not absolutely necessary, but adds greatly to the cost.

I use the BPR8HS-10 or a BPR8HS and set the gap to .030
MUCH more cost effective, and I change annually or sooner.

If the plug changes doesn't pick up the rpm's then try running on a portable tank of fresh fuel.

I suspect you had an amount of aged fuel left and you either run it out or drain it to use in your lawn mower.

 

[itguy]

Re: Loss of power...possible plug problem?

There was around 14 gallons of fuel in the tank and it was a couple months old. The boat ran fine a couple weeks ago so if it was old fuel I would think I would have had issues then. Someone else thinks there may be too much oil in the fuel...not sure.

I will put new plugs in and see what happens. I guess if it works temporarily and they foul again I'll be back to square one!