Mailing List flyrotary@lancaironline.net Message #62281
From: <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: Oil Scavenge Pump vs Custom Oil Pan
Date: Fri, 15 Jan 2016 01:43:16 -0500
To: <flyrotary@lancaironline.net>
Crank case venting should be as large an ID as is possible. The stock vent is too small for mild street use and not at all adequate for sustained high power applications. The rotors built up to factory specs leak like a screen door. So oil is contaminated with combustion products and debris. I build up side seal gaps at less than zero. So long as the 2 side seals and corner seal can move as a unit, everything is golden. Instant starting even when hot. Good for 10 races, shifting at 9,600 RPM,  then that engine becomes the spare and a fresh engine goes in for next season. On teardown the side seal gaps are still tighter than stock minimums.
 
Oil recovery systems need to enter the pan well below the level of the oil. This forms a one way valve where oil can return from a separator and stack up in the return line a bit higher than the oil level, but pan oil cannot be lifted up the return line by crank case pressure. Return lines also need to be as large a diameter as is possible. Foamed oil has no interest in flowing down a dash 4 return line. And rotaries foam the oil inside the rotors. Much worse than piston engines. Foamed oil is very light and tends to flow slowly.
 
Racing oils have many features that are a help in rotary engines. High film strength. High anti scuff content.
Large amounts of antifoaming agents. I use 40 weight RedLine racing synthetic in the crank case. I mix 1 ounce of RedLine racing 2 cycle oil in each gallon of fuel. The fuel is regular gas with no alcohol. You can use Mr Sohns gizmo to run oil through the stock system from a bottle of synthetic 2 cycle oil. No mixing required.
 
I can have any oil pressure I want because I use a three stage external oil pump and a dry sump oil reserve tank. I have 85 pounds at idle and as soon as the revs come up, a solid 100 PSI. My oil pan is a flat plate. Before we got all fancy with the oil system we ran the stock pump in our 12As. Take off the stock bug screen. It is too course to stop anything dangerous, yet so small it restricts oil flow. Next look at the sharp edged oil pickup tube. A flow disaster. Braze a large diameter 1/4" thick washer to the end of the tube. Radius the inlet so as to look like the bell on a trumpet. Lap the flange end flat and install it with no gasket.
It cannot fail if it isn't there. Drill and safety the little bolts. The pickups do fall off once in a while.
 
Marvel Mystery oil is a mystery. What is in it is the mystery and it has no place in an aircraft. I use it to wipe  rust off of things, as lubricant for drilling holes and for killing weeds. Engines survive in spite of Marvel Mystery oil, not because of it. Use the full one ounce per gallon of 2 cycle oil please.
 
No oil related failures since 1980.
 
Lynn E. Hanover 
 
   
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