[NSRCA-discussion] After run oil?

[Tom Simes]

The list is a little quiet this morning, and I'm troubleshooting a
possible delivery issue with AOL, so I thought I would lob in a question
likely to spur some discussion :)

For years I was in the "just run the fuel out and put it away camp". 
However, I had the occasion to send an engine back to OS because the
cylinder plating had failed.  To their credit, they replaced the whole
engine gratis, even though it was a year out of warranty.  Their only
comment on the receipt was to make sure I was using after run oil.

I don't think the plating failure was caused by not using after run, but
I do know that I replaced bearings in that engine very early in it's
service life and there was internal rust after < 2 gallons through it. 
At the time I put in stainless bearings and didn't worry about it
further.

Some things I *think* I know about after run oil....

Hobbico AR is Marvel Mystery Oil (MSDS documents are the same) and it
has no particular anti-corrosion properties.  My understanding is it's
basically a combination of solvents in a light carrier oil.

Silicone components in some engines (YS) may be damaged by some commonly
used AR oils.

ATF seems to be popular and has good anti-corrosion agents.

Rislone also seems to be popular - like MMO, lots of solvents but with
some added anti-corrosion agents as well.

Synthetic oils (Mobil 1) seem to be safe for all engine
components (including YS?).

When OS says in their instructions not to put AR oil in the carburetor,
they are specifically referring to not putting it through the needle
valve / spraybar.  Putting AR oil in via the carb barrel is fine, and
something like 1/4 - 1/2 tsp is an appropriate amount.

So, if you are using after run oil, what kind are you using and how do
you keep it from making a mess in your field gear?  I've been using
Mobil 1 5W30 and applying it with an eye dropper, but I'm looking for
suggestions.

Thanks

Tom
 
======================================================================
   "Z-80 system stack overflow.  Shut 'er down Scotty, the system's
         sucking mud" - Error message on TRS 80 Model-16B

Tom Simes                                       simestd at netexpress.com 
======================================================================