Ed Anderson wrote:

 >

Nope! Here it is.

Ed,
I can't help thinking that you're covering up the symptom with
this super seal.  Seems (at least on the surface) that you are
pressurizing the gearbox and really need a way to get the return
oil out of the gearbox and back to the sump smoothly.  I don't
know enough about your system, but is there some reason that
you can't increase the return line size or do other mods to let the
oil flow back by itself?  I really distrust the scavenge pump
idea since it becomes an engine failure item.

Bill
Long EZ builder & pilot
mechanical engineer

Thanks Paul

Hi Bill,
    I missed your message and asked Paul to resend it.  I agree with your
assessment and believe I may have found a couple of contributing causes for
the recent oil leaks.  When I installed the oil return fitting 7" lower on
the oil pan for better gravity drain, I used an AN-6/1/8"NPT fitting as I
had it on hand.  Well the AN-6 end of the fitting is fine, however the
1/8"NPT end has a smaller diameter opening than the AN-6/1/4" NPT use
previously.  The smaller opening returning oil clearly does not help.  I
intend to drill out the fitting to the AN-6 size.  The second and perhaps
more significant thing I found was that one of the hoses I use to vent the
oil pan had a crimp in it.  When I installed the new intake manifold I
failed to notice that the back of it was pushing enough on the hose to cause
it to crimp.

   Since I was getting oil leaks only at higher power settings, I suspect
that the crimp in the hose was pereventing "Blow by" gas from exiting the
oil pan and was therefore pressurizing the gear box.  So I will reroute that
hose to remove the crimp.

   So hopefuly fixing those two areas should lessen any pressurization of
the gear box.

   I too prefer not to use a scavenger pump and that is why I went looking
for  a better seal.  It may turn out that it was unneeded, but since I have
already ordered it, I am going to give it a try. So your assessment was on
the money.

Ed

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