lml@lancaironline.net Mailing List Archive

>>> ^ >> ^ >>>> FlyRotary <<<< ^ << ^ <<< >>> ! >> ! >>>>>>>>>><<<<<<<<< ! << ! <<< >> Rob, Leon has convinced me to run a thermostat along with cowl flaps, but I'm convinced that the oil should be mixed. I admit that I am biased because this just seems so EASY to me after racing 2-stroke bikes for 20 years. BTW, Walmart 2-stroke oil is about $7 a gallon. If you can not find 2 stroke oil go ahead and mix synthetic auto oil or aviation oil. An occasional use of a low ash 4 stroke oil will not cause problems; furthermore, the 2 stroke oil has great detergent qualities and can clean things up as long as the carbon deposits are not to bad (and no, I don't know what this point is!). The accepted ratio at this time is 128:1, or 1 oz per gallon. There are SAE reports from Mazda indicating that 200:1 might be OK. Yes, your understanding of how the pump operates is correct. This pump (as well as the Mikuni pumps used on motorcycles, snowmobiles and watercraft) is a variable stroke pump; the amount of oil pumped is determined by both the engine RPM and the position of the pump lever. If you decide to use the oil injection, note that the 'air bleeds' (I don't know what these are really called) at the end of the oil lines and bolted to the engine must be used. I think this was mentioned by Jon Lauter in an earlier post. Ken Powell kenpowell@aristotle.net ----- Original Message ----- -- From: RJohn15183@aol.com -- To: <flyrotary@olsusa.com> -- Subject: To pre-mix or not to pre-mix -- Date: Tue, 06 Feb 2001 15:26:04 EST >>> ^ >> ^ >>>> FlyRotary <<<< ^ << ^ <<< >>> ! >> ! >>>>>>>>>><<<<<<<<< ! << ! <<< >> I have flip-flopped on this issue myself several times. I'll think out loud on some of my internal arguments. Bear in mind that the vast majority of my flying is cross-country. I LOVE to go places. My point there is that my flying is not 1-hour cheeseburger runs or flying circuits around the patch. We drone along hours at a time. Sounds boring but I LOVE it! Now one of my arguments against the oil-metering pump is that I worry about the possibility of running out of oil before I run out of gas. I have 85 gallons max aboard and at 14 gph that's up to 6 hours max. Will the crankcase supply that much oil without running dry? There is a reason Lycosaurus has a 12 quart sump eh? So how tough would it be to build a bigger oil sump? Especially if I go plugs up and have to build one anyway? On the other side of that same coin though I have this metal image of buying the entire inventory of those little cans of 2-stroke oil at the general store in Podunk because I am somewhere that does not have a Sam's warehouse where I can get it by the gallon. SO I have this other mental image of carrying 5 gallons of 2 stroke oil with me on a long trip to make sure I can get there and back without buying anymore. BTW: let us not forget that 2-stroke oil is *expensive*. > And the argument that 2 cycle oil is designed to be > burned in a combustion chamber (as opposed to > crankcase oil) On that note one of my internal arguments FOR the metering pump is that aircraft engines are made to burn a little oil just like the rotary. Aircraft oil is formulated to burn cleanly just like the 2-stroke oil. For you folks that are running metering pumps may I suggest your try some Aeroshell and see how it works? PLUS Aeroshell is available every where I will ever land (on purpose anyway). 2-stroke oil is not. Back to lugging gallons of oil with me on long trips. Oh, Aeroshell is 8 bucks a gallon. What's good 2-stroke oil? At least twice that right? > Has anyone come up with a terrific way to mix the oil > thoroughly so that it's not laying in a puddle at the > bottom of the tank rather than well dispersed in the gasoline? Robin, It depends on the individual tank design but this one is a no brainer to me. Whenever I land I always have a *very* good idea of how much gas I will need. In fact it is a little game I play with myself. I usually call it within a half gallon. I even debated weather or not to even install fuel gauges in my plane. I don't need 'em, I know how much fuel I have. Anyway, before you buy fuel pour in the oil required for how much fuel you think you'll be buying. The turbulence of adding fuel will mix it pretty darn good. I think most people fall into the mental trap of waiting to see how much fuel is pumped first then adding oil. Now a new problem came up for me yesterday. I have seen the chain drive to the metering pump but I did NOT realize it had a control arm until the posts yesterday on that topic. I had foolishly assumed that since the pump was direct drive the engine RPM would control how much oil it put out! In fact I will venture a foolish guess and say that is why people who have just wired it wide open have not had oil loading problems when running at reduced power settings? Slowing the engine down slows the pump down and it pumps less oil. No? I WILL use a thermostat but I am still 'conflicted' about the metering pump! :-) Rob >> Homepage: http://www.members.home.net/flyrotary/ >> Subscriptions: http://olsusa.com:100/guest/RemoteListSummary/flyrotary >> Homepage: http://www.members.home.net/flyrotary/ >> Subscriptions: http://olsusa.com:100/guest/RemoteListSummary/flyrotary