Hey, engine was running on occationally so took the plugs out, the electrode was really clean on all of them so i think my plugs are a bit too hot for my engine. Went and got some colder ones and chucked them in and went for a burn pushing the bus pretty hard and when i got home no run on at all. Anyway here are the plugs i took out which are NGK B5ES, they have been in the bus for about a year of occasional driving and recently been a daily driver (since december 05) i think im running a bit lean. Wat are the effects of a lean engine besides temp?

Cylinder #1

CYLINDER # 2

CYLINDER # 3

CYLINDER # 4

the plug tips should be a light brown colour if all is well......yours are white...i think your right. a bit lean. but someone who knows what they are talking about will tell u for sure.

lean ritch would make them black brown is nice & make sure tjhat you need long reach plugs they will damage valves if they are wrong and you should be using shorts

Hmmm, this it wat i got from repco outta their catalog. B5ES is their code. And im pretty sure they arent damaging the valves, fingers crossed... Will a lean mixture do anything besides increase engine temp?

Mmmmm looking at them, id be quite happy with the heat range. Im with the others as I would be tempted to adjust your jetting a poofteenth richer tho. Just a poofteenth mind you.
Not a lot mind you as no colour at all is not really a bad thing.

What kind of driving was being done just before the plugs were pulled?
L8tr
E

Just been using the bus as a daily driver. I knew i was going to check the plugs so i drove down to work to pick up something, let the engine get to operating temp then drove it home pretty hard and shut it off as soon as i got home. Ill pull the new B6's out next weekend and see if they are fouling but since putting them in the engine hasnt run on once... not at all.

Yer K.
IMHO, Id be pretty comfortable with that colour.
See what they look like when you pull the new ones.
L8tr
E

Agree with tassupervee the colour on these is not either good or bad. but is more good than bad. I too would adjust mixture to be a little more rich. When lean the motor might experience runon as the heat in the chambers is what ends up igniting the fuel further. By going cooloer plug you are just making sure that part of the chamber is cooler and thus runon is not occuring. I think you might be masking the problem rather than fixing it. Do a plug cut of your new ones and see what you have. My guess might be that the plugs look clean/white and thus too lean and too cool. Just my thoughts anyway.

I would not nesseccarily just dump the new plugs though. Look at the colour and decide whether to adjust the micture and run them still or swap back to the old ones. My gut feelign is try the slightly rich mixture (maybe 1/16 of a turn) asnd see how this goes. you might find a slightly more drivable car than at present.

A lean mixture does a few things. some are over time some are instant.
1. increased chamber temps
2. increased oil temps
3. harder starting when cold
4. Increased fuel consumption. (most people will think that this is a sign of rich, which is is as well but, the issue comes from using more throttle to getthe vehicle moving.)
5. Tendency to burn valves due to increased head heat
6. tendency to ping/pink again due to increased inlet/chamber temps

all in all it is slightly better to run rich then lean.

Cheers

How do i go about making my mixture richer?

Here is some article on plug reading as well

http://www.superhunky.com/SparkPlug.html  (superhunky???)