Re: Synth Oil Sillyness

[mike tipton <mtipton@netten.net>]

Found this statement:

 2. Additives in oil might be different in new oil than old, which cause
 swelling and changes in seals, causing leak.

Well, while I worked at Lockeeds aircraft rework facility, We had a 
problem develop when the introduction of synthetic oil caused "problems"
with seals on engines, props and gearboxes.

These problems were leaks, reduced seal life, etc...  Just like on our
automobiles.

In late 1986 auto manufacturers began to pay close attention to the 
sealing devices used throughout the auto industry.  Alot of these
same manufacturers make aircraft sealing devices. The reason for such 
srutiny was the "soon to be wide use" of synthetic oils.

Many sealing devices were designed to operate around perameters of
organic based oils.  When synth oils were introduced to these same 
seals, they began to leak almost immediatly. Back to the drawing boards 
for alot of manufacturers  

In several aircraft I worked on, I seen the results of using a synth 
oil, where it wasnt suppose to be used, and vise versa.
In all cases the sealing devices were short lived, and leaked more than
they were suppose too!

In a particular jet turbine, Mobil makes the oil, its synyhetic, and
designed to operate within very strict perameters.  If you were to put
in a non synthetic, it would ruin the motor in a very short period of 
time.

It is true synth and organic oils are very different in composition and 
design.  Therefore,seals have to be design that can be used with either, 
or one.  If older sealing devices were designed around organic based 
oil,  then with the introduction of synth, things will more than likely
start to happen!

Rest assured though, I have read in a leading automotive industry 
magazine, that most seals designed today are of much better build
qualtily, and will work with synthetics quite well.

The auto industry is catching up with the rest of the world and using
synth oils.  Of course the cost will be absorbed by the consumer!

                                  M