Green

[mikeallen]

No nothing to do with the England goalkeeper :bouncyeng: But the colour of my spark plug at the porcelain & the electrode

Been keeping an eye on the plug colour since fitting the Breath sweet filter & JL3 just to be on the safe side & not running too lean but I am miffed at the greenish colour of the plug.

Have done choke tests at 1/4, 1/2, 3/4 & full throttle & nowhere does it indicate that I am lean. However after doing plug chops & checking the plug after a good run out I am a bit baffled at the Green colour of the plug porcelain & the electrode In fact one side of the plug is a dark grey & the other side is a greenish colour

Hope you can make it out from the pic


The plug is an NGK B8ES with a bit of town & fast 'A' road riding.

Using same crappy unleaded fuel from Morrisons & no change to my Rock oil two stroke mixed at 4%

Is it a case of green oxide indicates overheating the plug

Rapido 225, JL3, 28phbh on Breath sweet filter, AV264 x13 @p2, 50 pilot, 120 main, 40 slide, 60 choke.

Don't want to cause damage to my engine so any advice much appreciated

[minotaur]

this is a quote that i found on a 2 stroke site

Excessive green oxide indicates overheating the plug. a lot of spark-plug electrodes have an alloy composition that will oxidize green when subjected to high temperatures. The nickel oxide on the center wire and strap would show up first at the tip of the electrode (the hottest part) and progress from there. Some would suggest going to a colder plug. I suppose a lean condition could cause this as well.

[dirtyhandslopez]

Never seen green. See red occasionally and put that down to ethanol in the fuel. Very interested in this one.

[LeeLee]

Looking at the rest of the plug, I would say that the mixture could be a bit rich.(Depending on throttle position of course).. I would have thought this would be the signs of the plug beginning to break down. I would try another plug bruv..!

[mikeallen]

Bit of an update.

Changed plug to a B7 & gave it a good run out at all throttle positions including some 60mph long cruising. Basically the same good run I did this morning with the B8.

Did plug chops & also checked plug when I got back all reading a nice light tan colour as it should be

Could it be a case of the B8 breaking down

I was just a bit puzzled as all the plug colour charts on tinternet don't seem to mention a green coloured plug

cheers
mike