Dumb spark plug question: Metric or not?

>Your socket is too large in diameter to fit down into the spark plug well
>far enough to engage the hex. You can grind the end of the socket a little
>smaller in diameter to make it fit.

But it fit OK in the other three cylinder holes

wrote:
>
> I'm wondering if there is some kind of "crud" down
> there say wedged in between top of plug and sides of
> hole that is blocking the wrench form seating on the
> plug.
>
> Just seems like no matter what I do I cant get the
> wrench to 'seat" on the hex head of the plug!

Try to clean that hole with a steam cleaner. If that does not work... you
can try some cunning plan with epoxy and a use-once tool that you can make
(good luck with thay!), or you will have to remove the head to have a look
from below

I don't recomend any of the above though. Just keep on cleaning that hole,
it can´t be that hard to get it out!

There may not be enough room to use a straight wrench extension. Try a
u-joint or flexible socket extension. My 11mm plug socket has an outside
diameter of 21.5mm. It's hard to believe that the opening around the plug is
smaller than 25mm.


> wrote in message
...
> >Remove the little rubber inside the socket. Fit the socket on the plug by
>>hand so that you can feel it slide into place. If the plug has corroded in
>>place, you will need to use a piece of pipe as a handle extender on your
>>wrench. Make sure you are attempting to turn the plug counterclockwise.
>>The
>>plug will come out!
>
> Done the above but still no go
>
> My plugs are in a recessed hole abt 6 inches deep
>
> I'm wondering if there is some kind of "crud" down
> there say wedged in between top of plug and sides of
> hole that is blocking the wrench form seating on the
> plug.
>
> Just seems like no matter what I do I cant get the
> wrench to 'seat" on the hex head of the plug!

> wrote in message
...
> >Your socket is too large in diameter to fit down into the spark plug well
>>far enough to engage the hex. You can grind the end of the socket a little
>>smaller in diameter to make it fit.
>
> But it fit OK in the other three cylinder holes

3 out 4 of isn't bad.
Maybe a piece of the connector is stuck on the plug, look down in there with
a CSI lite.

Chas Hurst wrote:
> > wrote in message
> ...
>>> Your socket is too large in diameter to fit down into the spark plug well
>>> far enough to engage the hex. You can grind the end of the socket a little
>>> smaller in diameter to make it fit.
>> But it fit OK in the other three cylinder holes
>
> 3 out 4 of isn't bad.
> Maybe a piece of the connector is stuck on the plug, look down in there with
> a CSI lite.
>
>
Apologies for this not threading properly; my newsreader has purged the
older posts.

Pic of NGK BKR6EIX spark plug removed from 1997 NA (BP 1839cc engine,
standard tune). Don't worry - the centre electrode - the iridium one -
is supposed to look like that. Just to show it's in good condition and
the right plug for the engine.

http://www.peeble.com/car/plug1.jpg

Pic of above spark plug in 10mm (British terminology) spark plug socket:

http://www.peeble.com/car/plug2.jpg

Pic of spark plug showing model number:

http://www.peeble.com/car/plug3.jpg

Pic of calipers showing both plug and socket are 16mm across flats:

http://www.peeble.com/car/plug4.jpg

Close-up of caliper measurement:

http://www.peeble.com/car/plug5.jpg

They're good plugs; the service life is probably 50,000 miles or more
and there is a tiny improvement in miles per gallon. It's best to take
them out occasionally to ensure they don't get seized, as 10 years
installed in a low-mileage engine might be pushing your luck.

"Zog The Undeniable" > wrote in message
...
> Chas Hurst wrote:
>> > wrote in message
>> ...
>>>> Your socket is too large in diameter to fit down into the spark plug
>>>> well
>>>> far enough to engage the hex. You can grind the end of the socket a
>>>> little
>>>> smaller in diameter to make it fit.
>>> But it fit OK in the other three cylinder holes
>>
>> 3 out 4 of isn't bad.
>> Maybe a piece of the connector is stuck on the plug, look down in there
>> with a CSI lite.
> Apologies for this not threading properly; my newsreader has purged the
> older posts.
>
> Pic of NGK BKR6EIX spark plug removed from 1997 NA (BP 1839cc engine,
> standard tune). Don't worry - the centre electrode - the iridium one - is
> supposed to look like that. Just to show it's in good condition and the
> right plug for the engine.
>
> http://www.peeble.com/car/plug1.jpg
>
> Pic of above spark plug in 10mm (British terminology) spark plug socket:
>
> http://www.peeble.com/car/plug2.jpg
>
> Pic of spark plug showing model number:
>
> http://www.peeble.com/car/plug3.jpg
>
> Pic of calipers showing both plug and socket are 16mm across flats:
>
> http://www.peeble.com/car/plug4.jpg
>
> Close-up of caliper measurement:
>
> http://www.peeble.com/car/plug5.jpg
>

Well thanks, but the question remains unanswered. That question being "What
feature of the subject spark plug corresponds to 10mm?"
The thread size of the BKR6 spark plug is 14mm.

Here's what you previously wrote.

> Spark plug spanners (and *only* spark plug spanners) are sized by the
> thread major diameter here. A bit of Googling suggests the rest of Europe
> uses the actual across-flats measurement, so maybe the US does the same.
> You learn something new every day!

Chas Hurst wrote:

> Well thanks, but the question remains unanswered. That question being "What
> feature of the subject spark plug corresponds to 10mm?"
> The thread size of the BKR6 spark plug is 14mm.
>
> Here's what you previously wrote.
>
>> Spark plug spanners (and *only* spark plug spanners) are sized by the
>> thread major diameter here. A bit of Googling suggests the rest of Europe
>> uses the actual across-flats measurement, so maybe the US does the same.
>> You learn something new every day!

My only guess is that the BKR6xx plugs have a non-standard
thread-to-flats relationship. Normally 16mm across flats would indicate
a 10mm thread, but here it obviously doesn't. At the end of the day I
have all three common plug socket sizes, so it doesn't matter.

"Zog The Undeniable" > wrote in message
...
> Chas Hurst wrote:
>
>> Well thanks, but the question remains unanswered. That question being
>> "What feature of the subject spark plug corresponds to 10mm?"
>> The thread size of the BKR6 spark plug is 14mm.
>>
>> Here's what you previously wrote.
>>
>>> Spark plug spanners (and *only* spark plug spanners) are sized by the
>>> thread major diameter here. A bit of Googling suggests the rest of
>>> Europe uses the actual across-flats measurement, so maybe the US does
>>> the same. You learn something new every day!

To the above statement. Whitworth and British Standard wrenches and sockets
are sized by thread diameter. This is likely a rather clumsy carry-over to
spark plug sockets.
16mm or 5/8 has been a standard hex size for 14mm threads for decades. I
have no knowledge of a 10mm thread sparkplug being used in a Mazda. Most
10mm plugs are found in motorcycles.

> My only guess is that the BKR6xx plugs have a non-standard thread-to-flats
> relationship. Normally 16mm across flats would indicate a 10mm thread,
> but here it obviously doesn't. At the end of the day I have all three
> common plug socket sizes, so it doesn't matter.

Chas Hurst wrote:

> To the above statement. Whitworth and British Standard wrenches and sockets
> are sized by thread diameter. This is likely a rather clumsy carry-over to
> spark plug sockets.
> 16mm or 5/8 has been a standard hex size for 14mm threads for decades. I
> have no knowledge of a 10mm thread sparkplug being used in a Mazda. Most
> 10mm plugs are found in motorcycles.

It's strange you should say that; I bought those iridium plugs from a
motorcycle dealer.