Mark,
Yes and no with the OMP.
Forgetting about the small risk of failure of the OMP (which does happen),
in the Renesis engines manufactured until, I believe 2004, the ports squirting
the oil into the trochoids were insufficient (there were only 2 per rotor) and
they had multiple problems, so much so that Mazda, I am told, built a factory
just to rebuild the Renesis' at no cost to the owners. If you have a pre-2005
renesis with 2 injection ports per rotor don't even consider the OMP. If you
want to consider the OMP, that is a decision with pros and cons on each side
which I will not go into.
One way of mixing the fuel and oil is to get a large cappable poly syringe
or syringes . Fill it (them) with 2 stroke oil and while adding fuel,
inject the appropriate amount as the fuel is flowing. They used to do this with
a product called Prist for Turbine engines. (although they used aerosol cans
with a tube which attached to the filler nozzle.)
If you know that you are going to put 10 gal in your tank, when you start
fueling, squirt the stuff in in the beginning when you start to add your fuel.
Since the 2 stroke is or supposed to be miscible with fuel, adding it this
way especially with the initial agitation of filling, despite the baffles,
it should evenly distribute. If you want, you can rock the wings. Remember, the
baffles are not continuous and have relief ports at the bottom of each.
One question that I have about any of the 2 stroke oil bulk adding is is
there a difference between the brands on their misciblity?
Rich
In a message dated 5/21/2015 9:17:34 A.M. Central Daylight Time,
flyrotary@lancaironline.net writes:
Bill,
I used to pre-mix my oil & gas back when I was running auto gas
(non-ethanol), pumping into a fuel trailer at the nearby gas station. I
would pour the required amount of 2-stroke oil into the trailer tank, then add
fuel. By the time I was back at the airport it was well
mixed. After they started blending all mogas with ethanol, I was forced
to go to 100LL as my wing's adhesives are incompatible with alcohol. My
wings have a series of baffles, so adequate mixing became a
problem. So, I switched to the oil metering pump (OMP), using Richard
Sohn's OMP adapter and drawing from an auxiliary tank mounted on the
firewall. Now, I just have to remember to keep the oil tank full.
I often add a small amount of 2-stroke when filling the tanks, but that is
probably overkill.
It is my belief that the OMP puts the oil exactly where it needs to be,
directly on the apex seals rather than mixing in with the fuel only to be
burned up and blown out the exhaust, most of it never reaching the apex
seals. (Probably a topic for future discussion.) Anyway, I'm happy
with the OMP approach. It is a very simple pump and has proven effective
in millions of RX-7's and RX-8's. The one modification I made was to
fabricate steel oil lines to replace the plastic lines.
Mark S.
Lancair ES - 20B - pport