Spark Plugs

[Holden202T]

what you've just described is a "fouled plug" not "failed" i reckon a quick clean with a wire brush and some carby cleaner and you'll find they'll work again thats what i've been doing with my gemini ngk's

[Dec_head]

You would think so but for some reason the ngk's fail completely cleaning won't fix them i have tried.
And why they foul to the point of not working so easily i can't understand myself when the bosch plugs don't do it .
I am referring to the budget plugs not platinums or anything special.
Although my mate used ngk's with the platinum tip and the tips fell out inside his engine somewhere he wasn't very happy.

[charlay86]

http://www.ngk.com/glossaryImage.asp?imgID=721

They have inverse heat ranges... that might explain your problems

[Dec_head]

I experimented with different heat ranges over the years on over 20 different motorbikes either way same failures now i just refuse to use ngk.
I have even had several new plugs not work at all straight out of the box.
And new plugs wich were missing and farting on 2 strokes changed to another problem solved .
It is not as if it is a one off or one engine problem seems to be quite a well known issue with older bikes with a lot of riders choosing champion or bosch.
I took the risk rather then drive an extra 10 k's for bosch and bought them for my commodore and got burn't again.
Anyway this has turned into a spark plug debate and way off track i was merely suggesting that if he was using ngk's that the new cam putting the tune out and making it rich can cause plug failure as happened to me and changing them to new ngk's didn't last long and they failed again.
but the bosch ones didn't foul or fail and gave me a chance to sort out the tune and are still in the car now with no issues.

[Holden202T]

well you must be unlucky then!

all i've ever used is ngks and never had a problem ever, there was one time when i snapped one and had to go to the only place that was open at the time (kmart) and all they had was bosch ones ..... let me tell you they didn't last long, backfiring and carrying on ..... thats my only one experience with them and have never been inclined to use them since ..... stick with what i know .... cheap ass dodgy reliable ngks

[Dec_head]

Maybe you should give bosch a try in your gemini so you don't have to clean them all the time lol

[Holden202T]

well the above mentioned issues i had with bosch plugs were in the 202 when it was in the torana, and its now in the gemini

[Dec_head]

Yeah wrong heat range was my guess i bet they didn't foul up though did they lol

[Holden202T]

no they were just shit from the word go .... but they were what was "standard replacement" for that motor and thats all i ever use in ngk brand but i dunno what the numbers were.

just been wasting some time on the googlenet and found this:

spark plug heat range comparisons.jpg

also found alot of info about all things spark plug related at http://www.sparkplugs.com

[v6bucket]

Just a bit of advise when cleaning plugs, don't clean them on a wire brush as it can leave a metallic deposit on the porcelain thus causing a miss fire.