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skippydiesel last won the day on November 10

skippydiesel had the most liked content!

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About skippydiesel

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    ATEC Zephyr
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    The Oaks
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  1. Informative reply Onetrack. One small point that I might add - In piston aircraft engines, I always understood (?) that high octane fuels is required at higher altitudes (somewhere above 10,000 ft) tp prevent "knocking" in the low oxygen environment and of course allow for the development higher compression ratio (more powerful) engines. All this combined gives a tactical advantage (as you stated) by allowing allied aircraft to fly higher and faster, probably further (on a Gal of AvGas)
  2. Cetane rating for diesel (compression ignition fuels) - Octane is for petrol (spark ignition fuels). Yes I know it's not quite that cut & dried, as a hot low pressure petrol engine, with warmed fuel can burn kero/diesel/etc in a spark ignition combustion.
  3. Pleaseeease dont get me stated on diesel engines & injection types - Oh & by the way me thinks you have confused direct injection with indirect (at least in some of your comments)
  4. So why isn't it a standard inclusion in petrol ?? Price? Efficacy??
  5. Note: The Jabiru recommendations for unleaded fuel storage are at odd with the advice from the fuel company technicians which in layman's terms say - store the fuel in an airtight (non vented) container that is a t least 75% full. Fuel stored this way has a long (12 month?) "shelf" life. The fuel company advise makes more sense to me, as it is the volatile fractions which are most readily lost in a vented/open to atmosphere situation, with a resulting degradation of the fuels performance in certain conditions. By storing in an airtight container with a small air space (minimal oxygen ) the fuels volatiles are likely to be retained, thus preserving the fuels designed performance.
  6. The old saying "the proof of the pudding, is in the eating" -in the Rotax /ULP debate, I think that with so many units in operation, around the world, without drama (related to fuel) all the wise counsel regarding fuel QA , adulteration, aging, etc is good as cautionary advice , rather than any on going problem. The climate change debate is bogged down by countries claiming to contribute little to the problem or demanding more time to develop/pollute. Lead is much the same story, just because aircraft contribute very little is no reason not to try and phase it out ( yes I know that there is no viable alternative - yet!)
  7. Good oh! - I have no experience of STC'd engines so should probably not comment, but I just cant help myself; I am of the generation that saw the move from leaded fuels to unleaded. Having also lived in Europe for many years, I was familiar with high octane petrol for high compression engines - mainly sport cars and lower octanes for lesser engines (dont think Au had as much choice, certainly outside the major cities). We were always counseled against using lower octane fuels in high compression engines (cause "knocking" etc). Conversely using these fuels in lower compression engines might make us feel good but did nothing for the engine, just lightened the wallet for no gain. Whats all this got to do with aircraft engines? Perhaps nothing but the lessons learnt back then are still with me and the thought of using a fuel that the engine was not specifically designed/constructed for goes very much "against the grain" - I do appreciate that modifications can be made to adapt an engine and may be your Lycoming was designed from the outset to run on both but it still makes me uneasy. I am with Nev on the use of the correct fuel for the engine.
  8. That's okay then - I have about a 10 degree rise over ambient, within my cowling during climb. As expected this difference is reduced down below 5 degrees in cruise. I can accept a 3% loss of power - to overcome this would require a considerable increase in cost, complexity and some added weight - could easily nullify the benefit.
  9. Nev Nnev - lead is a pollutant in our atmosphere, does terrible things to the neural system/brain - especially in children. Why - Oh - why would you be an advocate ? ULP/PULP/MOGAS whatever, runs our cars and has done since about 1985 or so - it seem to be perfectly acceptable to Rotax 912/914's - no more risk than aviating itself. In fact AvGas is decidedly non beneficial to the Rotax - as I pointed out , why put AvGas into an engine that will not benefit from it/will only cause it harm - it can only be perversity or some other ego driven urge, it's certainly not logical. No offence Nev but the numbers are against you - most 912/914's run on unleaded and have done so for many thousands (if not millions by now) of hours with very few fuel related issues (probably less than AvGas and its potential to cause deposits - not every pilot has your skill /knowledge with engine management). It would seem you are unaware, all recent Rotax 912/914's are certified to run up to 10% ethanol/ULP - no problem (can't say I would want to but that's another debate) conditional on fuel storage & delivery systems also being compatible with ethanol. As for engines designed for AvGas - I agree with you - use AvGas!. Anything else has the potential to have a harmful (engine) outcome. Hopefully your bogeyman statement about "people can add what they choose to the mix" is largely a thing of the past and certainly not practised by the mainstream fuel companies.
  10. Lead! It seems to me that if the engine is designed for ULP, then it runs just fine on the stuff, putting AvGas in serves no beneficial purpose, other than to lighten your wallet & stroke your perceptions. On the other hand if its designed for AvGas and you use ULP without modifications (even with an STC) then problems may ensue.
  11. Agreed! except the X wind statement - how so? please explain.
  12. Hi Butch - The debate over additional fuel filtration on small diesels is almost as long as they have been around. These days the emphasis seems to be having the same micron filter as the OM WITH an additional nice big water separator and water warning system. I think the idea is that the filter(s) are more than good enough for removing solids but the OM system does not have enough capacity/early warning to stop you in time from trashing the common rail. Most conversations, I have followed, have the additional filter/water separator befor/upstream of the OM system but I guess that's up to the installer. Certainly there is little point in having a larger micron filter downstream and one needs to be careful that a smaller micron is not interfering with fuel delivery.
  13. No he's right on the ball - a lot of water in his fuel or is it a little fuel in his water - I get confused! On another note: I too have had dodgy fuel - many many years ago filled up (with diesel) at a no name el cheapo servo - got a tank full of something not quite diesel. Engine didn't stop but power so low that, on hill near our place that I would go up in 5th, down to 2nd with lots of smoke. Drained tank refilled and the car "came good" ! I have never used no name servos since and as I said had no problems at all.
  14. At my age I will take all the admiration you can dish out without any discrimination (high or low wing). High or low wing will make no diference to the 912 motivation itself. Fuel delivery & tank(s) may differ. Out of interest - why so definitely desirous of a high wing??
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