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sticky black stuff on spark plugs

Posted: Tue Jan 17, 2012 2:01 pm
by leerc
on changing the plugs on my nc30 and the 1st one i pulled out was covered in what looked like oul but was sticky goo'ey

it had alot red ex through it recently so i was hoping it could be that but since its not so bad on the next plug im dubious

opinions please chaps

off to tackle the fronts now

Re: sticky black stuff on spark plugs

Posted: Tue Jan 17, 2012 2:09 pm
by porndoguk
sticky black stuff sounds like oil mixed with combustion carbon, what colour was the smoke when it last ran? and what mileage has you engine done,

could be a sign of valve seals or piston rings failing.

Re: sticky black stuff on spark plugs

Posted: Tue Jan 17, 2012 4:21 pm
by leerc
alot iof white smoke from memory,it does every now n then pop a lil bit black out but not all the time

only plug that wasnt like this was the back right

19km but it wont be genuine

Re: sticky black stuff on spark plugs

Posted: Tue Jan 17, 2012 5:01 pm
by leerc
iv got some pics of the plugs ill try and stick them in here

Re: sticky black stuff on spark plugs

Posted: Tue Jan 17, 2012 6:49 pm
by leerc
Image

Re: sticky black stuff on spark plugs

Posted: Wed Jan 18, 2012 8:13 am
by leerc
pretty sure i can smell petrol in the oil-its doomed

Re: sticky black stuff on spark plugs

Posted: Wed Jan 18, 2012 9:15 am
by porndoguk
leerc wrote:Image
that doesnt look good or promising mate :s

what you need to do is a compression test first. (to rule out or prove the rings are fucked)

next is then to take the rocker cover off, and put a teaspoon of oil above the valves inlet and outlet over night and if its gone the next day then you know a valve seal is weak,

id do these before comitting to a new engine because valve seals are a few quid each and then will require a new head gasket, whereas a piston ring set isnt going to be cheap,

hopefully its valve seals

Re: sticky black stuff on spark plugs

Posted: Wed Jan 18, 2012 3:19 pm
by leerc
the old oil smelled a bit of petrol,changed that lined the bores with a lil oil (was advised this on the basis of my oil was so thin,used old but cleaned plugs) and its pulling alot better but still splutters and im yet to check the plugs

the place i did my licence with have a garage and are going to have a look tomorow free so should have a answer

Re: sticky black stuff on spark plugs

Posted: Wed Jan 18, 2012 3:38 pm
by porndoguk
Where you located?

Re: sticky black stuff on spark plugs

Posted: Wed Jan 18, 2012 4:04 pm
by CMSMJ1
I don't reckon it is that bad..

Clean the plugs up and clean, as much as you can without dropping shit in it, the recesses where the plugs live.

Nip them up, run the bike for a few days and take them out.

I reckon it is just old and mankyness...

Petrol in the oil is a sign of a shagged fuel tap and stuck, worn float needles. That can be easily fixed.

Remember to check the easy things..it is likely to be simple..