Oil on spark plugs.

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AyzenShiro
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Oil on spark plugs.

Post by AyzenShiro » Mon Sep 02, 2019 7:11 pm

Hi guys,
recently i bought nc30 in decent condition, it was sitting in garage for about 6-8 months so first step was fresh oil, fresh fuel, charge battery etc. but when i get to spark plugs ...wel there was huge suprise waiting for me, spark plugs ware bearly screw in, i was able to unscrew it with my bare fingers, and everything was covered in black oil:
Image

any idea whats going on, or what went wrong?

cheers

magg
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Re: Oil on spark plugs.

Post by magg » Tue Sep 03, 2019 2:01 am

Wasn't running when you bought it? May have been decent appearance but engine could be another story. Two cylinders oily, what about the others. You could simply make should all plugs are clean and try starting. No run or poorly running with much exhaust smoke suggests engine needs rebuilding.

richyrd5
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Re: Oil on spark plugs.

Post by richyrd5 » Tue Sep 03, 2019 8:25 am

Doesnt look good.....only thing to do is take them all out,clean them and put them back in,fire it up and hope for the best...you will soon find out if it's a worn engine!!..but also if the plugs were loose it could be spark plug hole gaskets leaking into the recessed and fouling them,but looks to me as if engine is burning oil.....good luck and let us know what happens.....

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AyzenShiro
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Re: Oil on spark plugs.

Post by AyzenShiro » Tue Sep 03, 2019 3:38 pm

magg wrote:
Tue Sep 03, 2019 2:01 am
Wasn't running when you bought it? May have been decent appearance but engine could be another story. Two cylinders oily, what about the others. You could simply make should all plugs are clean and try starting. No run or poorly running with much exhaust smoke suggests engine needs rebuilding.
All plugs are like that, bike was running fine, i did test run and it was fine, just had to stay on choke for a while.

magg
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Re: Oil on spark plugs.

Post by magg » Tue Sep 03, 2019 9:57 pm

Maybe plugs came from another bike and owner failed to tighten them correctly, who knows. You could ask or just clean them and keep riding if the engine sounds good and goes well. No need to create work unless there is an issue. Choke to start but once running just a fast idle 2000-3000 rpm for 30 seconds or so and then ride away, depending on ambient temperature.

ArizonaRVF
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Re: Oil on spark plugs.

Post by ArizonaRVF » Sat Sep 07, 2019 3:26 pm

Based upon the color of those plugs and the amount of oil, I would have to believe the rings are questionable. I would recommend a leak down test.

Ozzibiker
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Re: Oil on spark plugs.

Post by Ozzibiker » Fri Nov 15, 2019 2:50 am

Any news?

Which country are you in?

Foxy400
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Re: Oil on spark plugs.

Post by Foxy400 » Sun Nov 24, 2019 11:07 am

Yes, I'd like to know how this one turned out as well.

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NGneer
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Re: Oil on spark plugs.

Post by NGneer » Thu Nov 28, 2019 11:12 am

Another possibility is that your rocker cover gasket(s) leaking a bit. I had this once and it allowed oil to pool in the plug recces giving me a VERY oily plug - on the outside anyway. That coupled with the finger tight plugs would possibly allow the oil it to seep down the threads into the combustion chamber and foul up the plugs. Just a thought.


I would either give the plus a very good clean or just bit the bullet and get some (Quality) new ones, make sure they a re-fitted correctly and then go for a decent run on the bike. Have a look at the plugs when you get back and that shoould let you know if you have solved the problem or if there is something more you need to chase down.


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