[NSRCA-discussion] After run oil?

[Tom Simes]

On Wed, 9 May 2007 14:42:00 -0500
"wgalligan" <wgalligan at goodsonacura.com> wrote:

> OK.... time to open this can of worms again.   Are there some types of
> 
> additives that can cause fouling or glassing of the plug element?  It
> seems  to me after I stopped using after run oil my plugs seemed to
> last longer.  I  am like Dr. Mike, just run it. I usually run the
> engine dry if I know its  going to set up for a spell. When I take the
> engine apart even after running  the engine out of fuel there is still
> a LOT of oil in the crank.  I am sure  if the engine is going to sit
> unrun for extended periods its a good idea to  lube the engine by
> taking out the plug and running plenty of an  anti-corrosive type of
> lube through the engine to keep the crank and sleeve  from developing
> rust.

What's the average relative humidity where you and Dr. Mike are?  When I
lived in Arizona and New Mexico, the RH was so low I just didn't have to
worry about corrosion.  Now that I live in Anchorage, high RH, a
proximity to salt water and huge temperature swings combine to make
corrosion a big issue.  I fly all winter long and when cold soaked gear
is moved back into a warm environment, visible condensation forms all
over it.

While corrosion prevention is part of the picture, I'm a little
surprised that nobody has mentioned softening carbon deposits as a
feature of using after run oil.  The high solvent content in Marvel
Mystery Oil or Rislone should help mitigate some of the carbon build up
in the 4 stroke crowd.  As far as I know though, both those solutions
would be a definate no no in a YS due to their effect on the silicone
components.

With regard to the plug fouling quesion, MMO has been used for years
in aviation circles (100% scale) as a fuel additive to help counteract
lead fouling.  However, I would definately stay away from any of the oil
additives with zink compounds in them though (Slick 50, Motor Medic,
STP...)

Thanks for the information guys :)

Tom
 
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Tom Simes                                       simestd at netexpress.com 
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