I do not use Champion plugs. In the past I have had 1 out of 4 beeing bad
out of the box.
I have (with another company) done extensive reasearch on plugs with a dyno
and 5 gas analyser and the best plugs that we found were Nippin-Denso and
Bosch. Champions were the worst because the resistance varried 20,000 to
40,000 ohms wen they got hot (normal running temp) and sometimes went bad
altogether.
ND (whick makes Accel. ND plug colored yellow) and Bosch had the lowest
variations (+ or - 1,000 ohms) of all.
Steve Darby
Sports Cars Int'l
Jim Stuart wrote:
> Prompted by a tech tip in Moss Motoring, I wrote a reply, copy to the MG
> list & several others, that blindly using anti-seize on spark plugs was
> not a good idea. To summarize, Champion spark plugs have an anti-seize
> coating from the factory & other products are not recommended. Perhaps
> other spark plugs do also, I do not know. Never use any coating without
> consulting the owners or repair manual first. Many dry coatings now
> exist & may be present on aluminum cylinder heads that may render
> anti-seize redundant, at best.
>
> I am not saying that anti-seize should not be used, only that caution
> should be used first.
>
> The other point that I tried to make was that there are 2 grades of
> anti-seize, low temp & high temp. Low temp is great for suspension
> bolts, not good for exhaust manifolds. High temp is more expensive, but
> can be used every where.
>
> The original problem that Dave had where the spark plug had aluminum in
> the threads is a common indication of cross threading. This is easy to
> do with an aluminum head. The shop manuals & some spark plug boxes
> contain installation instructions that few bother to read. Spark plugs
> are to be threaded by hand until they reach the seat, then are turned a
> further amount dependent upon design & the use of a gasket. It is
> impossible to cross thread by hand unless King Kong shrinks his fingers
> to fit a little spark plug in an often hard to reach location. The plug
> holes should always be chased & blown out before installing new plugs.
>
> The best mechanic I ever knew tried very hard to teach me a little of
> his skill & knowledge. "If its hard, you are probably doing it wrong."
> He must have told me that a hundred times, & it certainly applies to
> starting threads in aluminum.
>
> Jim Stuart
|