[s-cars] spark plug removal problems

[Matt Russell]

Chris, et al-
IME, that is a pretty good description on how most techs do it.

One thing to add, is that there IS a tool specifically designed for this job
which works better than a conventional tap.  Mac Tools sells a set of spark
plug rethreaders.  I don't think Snap-On carries anything similar, IIRC when
I researched this.... or Snap On buys them from the same company that makes
them for Mac.

These work similar to a tap, however they drop down into the spark plug hole
first, and are then snugged up (to secure to the threads correctly) and then
"backed-out" of the hole, which cleans the threads starting from the
(hopefully) GOOD threads that are left in the lower part of the cylinder
head and works it's way UP.  A specially designed tip gets the blob of
grease which catches any filings. Obviously cleanliness is still important
but the tool does a better job of catching the shavings than a tap.

I think I paid 89 bucks for a 3 piece set on sale. Just tried to find the
part number on their website, but it won't pull up. My set has: SPKTHR03
listed.
http://www.mactools.com/Product/tabid/120/productid/320132/variantid/310891/Default.aspx

HTH,

Matt, CO
92 s4
(back to lurk mode)




On Fri, Apr 24, 2009 at 8:20 AM, <Chris> wrote:

>
>
> Gentz,
>
> I am not a fan of using a tap in the spark plug hole in this application
> while the engine is in the car. I'm wondering if it might be safer to
> just liberally coat the threads with a product like kroil to break down
> any buildup and possibly leave clean "enough" threads?
>
> With that being said I witnessed an "old school" mechanic too many moons
> ago that I care to admit use a tap to clean up the spark plug threads
> before.
>
> He rotated the engine so that the cylinder in question was close to
> top dead center, and then inserted an immaculately clean piece of cloth
> ( I believe part of a clean cloth diaper) through the hole into the
> cylinder and rotated the engine bringing the piston higher up to help hold
> the cloth in place.
>
> This part is hazy, but I seem to recall he applied a small amount of
> grease to the exposed portion of the diaper to catch debris.
>
> He then proceeded to clean the threads with the tap using a vacuum to
> remove debris. After cleaning the threads he cleaned with the vacuum and
> finally pulled the cloth out removing "the rest" of the particles.
>
> I have no idea how truely effective this method is, just thought I would
> share it.
>
>
> HTH
> Chris
>