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About scsirob

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  • Birthday 03/05/1963


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  1. Jabiru seems to not know that. They have used sealant on the rubber rings of the intake manifold from day one. They also use sealant on the oil pump that also has O rings installed, both on the back plate as well as the housing. On the Gen-4 engine they have changed the back plate design to include a second O ring (found in the CAMit engine), and they removed the sealant requirement there.
  2. Can we add Zoche to this list?
  3. This is my local experience in The Netherlands. I ran my previous Jabiru 3300 exclusively on Mogas (Euro-95) without ill effects. My current CAMit 3300 has 150 hours on it with Mogas as well. Last year after local authorities upped the Euro-95 ethanol content to 10% I started to notice rough running in some situations. I moved to Euro-98 BP Ultrium. This is labelled E5 which means up to 5% ethanol, but we have written confirmation that BP Ultrium for now has zero ethanol in it. Mogas keeps the engine relatively clean.
  4. I've made several prototype panels using a simple jigsaw for the holes. File and sand for good fit. When entirely happy, I then drew them in a simple CAD program and sent the resulting AutoCAD file to a local waterjet shop. €100 for three panels. Then had them stove painted for another €25.
  5. For our visiting friends from abroad, please note that on November 7th, The Netherlands will have a new CTR and changes to the airspaces around Lelystad Airport (EHLE). It will be class D airspace with mandatory radio contact, crossing clearances etc. Please make a mental note and check the AIP here: https://www.lvnl.nl/eaip/website_EFF_10OCT2019/2019-09-12-AIRAC/html/index-en-GB.html
  6. It's attached to the input side of the carb. The largest risk of ice forming is at the opposite side, at the butterfly. Especially with low power settings and the butterfly almost closed. The engine is a huge air pump. At 4600 rpm and 1200-1350cc displacement, you are looking at about 40 liter of air per second passing through that venturi. That's a lot of cooling capacity. Having 50W or 100W of electric heater on the outside of the carb body won't make a dent in the temperature of the mixture passing the butterfly.
  7. From the pictures it looks like it is on the input side of the carby. That makes no sense. No amount of available electric power on that side will significantly raise the input air temperature enough to avoid carb ice. There's other electric carb heaters producing about 50W that attach to the butterfly side where it may help a bit, and they are hardly effective. I'd opt to remove this pre-heater contraption and find a way to install proper hot air carb heat from near the exhaust pipes
  8. Nope. The frequency didn't change. Only the identifier did. In 8.33 world they don't speak of frequencies, they speak of channels. And Channel 129.830 happens to transmit and receive on 129.825MHz. The only thing that changed is the bandwidth. If you keep down your voice, your 25kHz radio will transmit nicely within the 8.33kHz wide channel. And you'll be able to hear those 8.33kHz stations just fine, but you may have to turn up the volume a it. The only problem is that your 25kHz radio may splatter over the adjacent 8.33 channels.
  9. You are kidding, right?? *THE* documented way to even out left-to-right EGT's in Jabs is to tilt the carby slightly to the left or right. The only reason this has any effect is because the poorly mixed stream hits the manifold divider, guiding more or less fuel to the left or right bank depending on offset of the carb atomizer and air stream. If the fuel was mixed properly, any tilt would have zero effect. I wish I could find the video again, but Pete Krotje, long-time USA dealer for Jabiru, had a transparant manifold made, to study what goes on. It shows solid fuel droplets coming from the
  10. The only real way to change things is to separate the carby from the plenum. This will allow the air+fuel droplets to change into a real mixture. Right now the fuel droplets simply don't have time to atomize and mix before getting to the plenum. This means puddles of fuel in unpredictable places and uneven mixture that changes seemingly random. Limbach used to have a setup where the carby was on top of the engine, and the fuel/air mixture had to travel half a meter through an aluminum tube to get to the plenum below the engine. This worked a lot better.
  11. scsirob

    Iridium plugs

    Plug temperatures have more to do with the ability to dissipate heat in balance with the amount generated by the engine. Heat Range : NGK Spark Plugs Australia | Iridium Spark Plugs | Glow Plugs | Oxygen Sensors | Ignition Leads | Ignition Coils Considering the strict ranges dictated by Jabiru for CHT and EGT, I would suggest that differences in installations are not much of a contributor. Jabiru users usually run their engines just below recommended maximums, or they struggle to keep the engine run cool enough and plug heat range is least of their worries. For EGT the user has no control over
  12. scsirob

    Iridium plugs

    I'm confused now. What fiasco? Are you saying that plug temperature is a factor? Where's the proof? It's not for a lack of available plugs, D7EA and D8EA are just as abundant as D9EA, but I have yet to see any evidence or even hints that this may be a good idea. You are not encouraging people to deviate from the manufacturers choise, are you??
  13. scsirob

    Iridium plugs

    Straight from the horse's mouth : PLUG STUDIO / NGK The resistor is not there to make the points last longer, it's there to stop RF from traveling back into the ignition wires and causing noise. AMPS are not a factor. The ignition system is a high VOLTAGE system (20kV+) with a limited amount of energy (<50 milliJoules) available. That means very low amps. Lets take 1mA as an example. At that current, the loss across a 5kOhm resistor would be 5V. Now how much impact would losing 5V out of 20.000V have? Even if you'd lose 50V (@10mA), or 500V (@100mA), the effect would be negligible.
  14. scsirob

    Iridium plugs

    NGK does not recommend using their product on aircraft engines at all. I can't find a link right now but recall seeing something along the lines of "Not for aircraft use" on the box that the NGK spark plugs ship in. The gap spec for the D9EA comes from Jabiru, we must take their word for it that that's a good starting point in their engines. As for gapping in common terms, NGK FAQ ( FAQ : NGK Spark Plugs Australia | Iridium Spark Plugs | Glow Plugs | Oxygen Sensors | Ignition Leads | Ignition Coils ) says the following: "What is the maximum I can open or close the gap? For nickel spa
  15. scsirob

    Iridium plugs

    Agree. The energy has to go somewhere. Without a spark plug to dissipate the energy, it will find some other path. That may well be inside the magneto, causing irreversible damage to internal insulation. Can't see that I made any recommendations, other than not to fiddle with the Iridium spark plug gaps.
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