Uneven spark plug condition

[Evcamp]

I have a 1997 XP with a brand new rebuilt engine. I started it for the first time on the hose today and after about 3 minutes of running I pulled the plugs. Mag side was brown and pto side was perfectly clean and looked brand new. Anyone know what could be wrong and how to fix it?
thanks
Evan

 

[etemplet]

I wouldn't run it that long on the hose. I have in the past but the water seal gets awful hot with no water cooling it. I'd take the ski to the water and ride it. There is likely a lot of oil and/or assembly lube in the engine that needs to be burned off. Take the ski to the water and do the proper break-in, stopping every so often to let it cool down and monitor. That engine is gonna take some time to settle in so you can't tell a lot with the spark plugs just yet. Checking and monitoring the plugs is a good idea. I always add extra oil to the fuel when breaking in a new engine. At least 80:1 in addition to the injection system lube.

NOTE- If you suspect that cylinder is running lean (not getting proper fuel) that is a concern. Could be carburetor adjustment or issue with the carbs. Did you rebuild them and set Pop-Off... such as that?

 

[Evcamp]

I’m planning on putting it in the water tomorrow. The carbs were rebuilt 2 years ago but have been sitting for awhile during the rebuild. I’m running premix in it for the break in but still don’t know why one plug is brand new and one almost looks burnt. If I were to rebuild my carbs, where is the best place to buy a good kit?
thanks

 

[KyleW2]

I’m planning on putting it in the water tomorrow. The carbs were rebuilt 2 years ago but have been sitting for awhile during the rebuild. I’m running premix in it for the break in but still don’t know why one plug is brand new and one almost looks burnt. If I were to rebuild my carbs, where is the best place to buy a good kit?
thanks

OSD Marine. I’d go ahead and rebuild them if I were you. For a fresh engine, I’d want everything to be fresh

 

[etemplet]

Did you determine what caused the last engine to fail? I always try to identify the root cause which can be difficult. I second @KyleW2 on the rebuild of the carbs. I had trouble getting carb kits from my supplier. I guess everyone is fixing the old skis out of necessity. Good Luck !