Oily spark plugs? Bad sign..

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
hardnutdvd
Senior Member
Reactions:
Posts: 1406
Joined: Fri Jan 01, 2010 8:50 pm
Bike owned: RVF400 NC35
Location: Bedford, Bedfordshire
Oily spark plugs? Bad sign..

Post by hardnutdvd » Sun Mar 13, 2011 8:48 pm

I took my plugs out today and all four are covered in oil on the thread. the tip where it sparks looks fine but the rest of it on all 4 were dripping in the black stuff. from the thread up to the washers... :(
I'm no way an expert but this aint a good thing is it...

i have done a search and it looks like it could be caused by a number of things,
the bike doesn't smoke, it starts first time everytime with no drama's, ticks over lovely and it pulls like a train when out on the road,
am i right in thinking it could be anything from simply running too rich to something very complicated (for novice) valve stem seals and piston rings
i wanted to ask what should i check first and the process of eliminating the causes..

User avatar
CMSMJ1
Moderators
Moderators
Reactions:
Posts: 9806
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: Oily spark plugs? Bad sign..

Post by CMSMJ1 » Sun Mar 13, 2011 9:22 pm

I would say a bit of oil is normal. Swimming in it not so cool, but certainly not ragnarok time and the end of the world.
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

hardnutdvd
Senior Member
Reactions:
Posts: 1406
Joined: Fri Jan 01, 2010 8:50 pm
Bike owned: RVF400 NC35
Location: Bedford, Bedfordshire
Re: Oily spark plugs? Bad sign..

Post by hardnutdvd » Sun Mar 13, 2011 9:32 pm

would this be classed as swiming?
or normal :pray:

Image

User avatar
CMSMJ1
Moderators
Moderators
Reactions:
Posts: 9806
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: Oily spark plugs? Bad sign..

Post by CMSMJ1 » Sun Mar 13, 2011 9:42 pm

no, don't reckon so. Pretty scabby, but not impending engine failure..

When were they last changed? Were they torqued up properly when last fitted?
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

arsey30
Senior Member
Reactions:
Posts: 1456
Joined: Tue Apr 29, 2008 9:13 pm
Bike owned: ftr223 650 bros
Location: Surrey
Re: Oily spark plugs? Bad sign..

Post by arsey30 » Sun Mar 13, 2011 9:51 pm

A small amount of oil needs to pass the valve stem seals and oil control ring to lubricate valves and piston.
On combustion it has no where else to go really.
Excessive oil will be blown out of the exhaust as smoke on the exhaust stroke, but if the plug contacts are not contaminated and the is no excessive smoke or oil consumption, I would say that it indicates nothing.
I have seen many plugs like that one, and ignore it if no indications of engine wear.

If 1 was a lot worse than the rest, I might investigate, as it would indicate some problem but not if all the same.

Considering the recent claims of 120,000km, engine wear is the last thing I worry about, even the NC 30 from Hell has done 122,000km

Dave.

hardnutdvd
Senior Member
Reactions:
Posts: 1406
Joined: Fri Jan 01, 2010 8:50 pm
Bike owned: RVF400 NC35
Location: Bedford, Bedfordshire
Re: Oily spark plugs? Bad sign..

Post by hardnutdvd » Sun Mar 13, 2011 9:56 pm

not sure when they wre last changed or if torqued properly as they was in the bike when i bought it last september..

dobbslc
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 1226
Joined: Fri May 02, 2008 8:06 pm
Bike owned: 3TJRRSP TRX850 XV750 cafe
Location: Hertfordshire
Re: Oily spark plugs? Bad sign..

Post by dobbslc » Mon Mar 14, 2011 10:41 pm

Mate it looks to me like your valve cover gaskets have gone thats all, If the plug tip is clean but the bit above the threads is oiled it could just be oil running down the plug tunnels. I would say you just need to get new rocker/valve cover gaskets and touque them correctly.
I know this as I drive a Vauxhall with an ECO-TEC engine........... :smile: :smile:
it looked exactly the same.

hardnutdvd
Senior Member
Reactions:
Posts: 1406
Joined: Fri Jan 01, 2010 8:50 pm
Bike owned: RVF400 NC35
Location: Bedford, Bedfordshire
Re: Oily spark plugs? Bad sign..

Post by hardnutdvd » Wed Mar 16, 2011 1:48 pm

so differences of opinion then??
leave it and sort it.

if there are things i am able to fix myself to sort it out then i will do, but if it isnt gonna kill the bike through the summer i'll leave it be rather than take it to a garage

User avatar
CMSMJ1
Moderators
Moderators
Reactions:
Posts: 9806
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: Oily spark plugs? Bad sign..

Post by CMSMJ1 » Wed Mar 16, 2011 3:44 pm

if it was your valve cover gaskets then even a child could replace them...
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

User avatar
uber pikey
Site Supporter
Site Supporter
Reactions:
Posts: 941
Joined: Sun Aug 15, 2010 9:58 pm
Bike owned: NC30, GS700e GSX750 katana pop
Location: Telford/Wolverhampton
Re: Oily spark plugs? Bad sign..

Post by uber pikey » Wed Mar 16, 2011 4:07 pm

I take it that you removed them to replace them? If so clean them up, put them back in and run the engine for a couple of days. You can then remove them and check to see if it's happening over a short period of time or longer.
It seems to be fine as it runs without any smoke. Have you monitored oil levels since you had it? is it going down at all over a period of time that you have to top it up regularly?
I saw it so I took it!


Post Reply