White spark plugs - Running lean?

[Paddy_g46]

After having the plugs out today to do a compression test the tips of my spark plugs were a bit white, so im thinking the car is running lean.

So what do i need to do to doible check it and fix it?

Patrick

 

[Russ_16v]

get it on a good set of rollers and get the AFRs checked fella, and see whats what

 

[sideways danny]

plug colour will only tell you roughly what the fueling was doing a few seconds before turning it off

 

[Paddy_g46]

get it on a good set of rollers and get the AFRs checked fella, and see whats what

will any rolling road do this?

plug colour will only tell you roughly what the fueling was doing a few seconds before turning it off

My mate said something like that, so its not so much that the plug is stained over a period of time just at the instant?
If that is the case why do i always read about telling how it runs by plug colour? In a haynes manual for example?

 

[powey]

Its true, when setting up a carb on a bike you do a full throttle run but then switch it off at WOT

 

[Paddy_g46]

Its true, when setting up a carb on a bike you do a full throttle run but then switch it off at WOT

at wot? :rasp:

 

[sideways danny]

Long term bad running can cause damage to the plug. There's a few clues can be taken to engine condition, but fueling is quite complex so plugs aren't the way to analyse it

 

[Russ_16v]

Most rolling roads do mate, just check before booking

 

[powey]

at wot? :rasp:

Wide open throttle

 

[mattjk]

Maybe you need a colder range spark plug?

 

[Paddy_g46]

Maybe you need a colder range spark plug?

whats that then?

 

[mattjk]

A colder plug wil disspate more heat

See here

http://static.howstuffworks.com/gif/ignition-system-hot-cold.gif

I dont know what car/spec you are running so it could be running lean

My Ecoexplod engine had white deposits on the spark plug then changed from heat range 5 to 6 and now looks better

 

[MAXIBOY]

whats that then?

shouldn't do on a standard motor though..

 

[Paddy_g46]

iv got a valver that had headwork and is running kent cams and verniers.

 

[MAXIBOY]

yeah..but standard plugs should be fine..i run colder plugs but only because of the turbo..i think if you are running lean theres a fault somewhere its not because you need colder plugs.

 

[powey]

yeah..but standard plugs should be fine..i run colder plugs but only because of the turbo..i think if you are running lean theres a fault somewhere its not because you need colder plugs.

Again talking from a bike backround a friend blew a hole in his piston due to messing with different temperature plugs instead of setting up the carb