What should an OX66 spark plug look like?

family affair

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For those of you that are confident your engine is running properly, what do your plugs look like when you pull them? My '99 225's are translucent black and wet, but not fouled. After reading Sal's post on the o2 sensor, I'm wondering if this could be an issue for me.
If what I have is not normal, would dirty injectors cause a similar issue?
 

grady33

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Looked at mine while winterizing and they were clean, dry and a few had a little carbon but very very little. I use ring free every fill up and only use non ethanol fuel. Cleaning the 02 sensor is a must every year as is replacing spark plugs. I usually keep a 2 sets on the boat just in case. The other things that need attention are the low pressure fuel pumps and vst filters. I replace my pumps about every 3 years. They are not the expensive. I clean the 02 sensors very carefully with ring free. Hope this helps. Good luck.
 

seasick

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grady28 said:
Looked at mine while winterizing and they were clean, dry and a few had a little carbon but very very little. I use ring free every fill up and only use non ethanol fuel. Cleaning the 02 sensor is a must every year as is replacing spark plugs. I usually keep a 2 sets on the boat just in case. The other things that need attention are the low pressure fuel pumps and vst filters. I replace my pumps about every 3 years. They are not the expensive. I clean the 02 sensors very carefully with ring free. Hope this helps. Good luck.

I compare all the plugs to each other to look for differences. There shouldn't be a lot on SXs
Here is a decent article on plugs
http://www.gnttype.org/techarea/engine/plugs.html
 

family affair

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I know what a plug should look like from a 4-stroke, but rarely have I seen a nice tan plug out of a 2-stroke. Should I expect a tan plug (void of carbon or oil) from a properly running OX66?

Grady 28,

How many hours do you put on in a year? I wondered why you replace plugs annually. Unless the electrode is eroding or another issue is evident, plugs don't need to be replaced too often.
 

freddy063

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I learned something this year, I had a plug that looked just like new, turned out being a coil, plug never fired , and the sick thing is was like that for two years till I found the trouble, motor ran ok but not great. :bang
 

seasick

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family affair said:
I know what a plug should look like from a 4-stroke, but rarely have I seen a nice tan plug out of a 2-stroke. Should I expect a tan plug (void of carbon or oil) from a properly running OX66?

Grady 28,

How many hours do you put on in a year? I wondered why you replace plugs annually. Unless the electrode is eroding or another issue is evident, plugs don't need to be replaced too often.

The center porcelain on mine are tan after a season. The metal inside shell is often black with light buildup.
I ran less than 100 hours this season I guess, about 400 nm. I do replace my plugs in the spring AFTER I start the motor and burn off the fogging oil etc. My plugs are cheap about 3 bucks a piece so replacing them is one of the lower cost maintenance items. If they were platinum or iridium, I would plan on more usage between changes.