jetboy

Jabiru carb version has different float system to Rotax, AFAIK is the float valve rubber tip in good condition? also the spring inside the valve working properly? I replaced my valve some years ago because the carb would leak a little while parked It still does (possibly needs a new seat) but I turn the fuel off at the end of the day per the manual

Its good to evaluate buying vs renting right at the start. True that nobody really knows what type you are going to prefer to own but that can be changed later anyway, every $300 you spend building hours in a hire is $300 less available to buy one (less the fuel / mtce costs of course) but it adds up quickly consider on average you need 70hrs training to go to PPL. I did all my training at an aero club and like any organisation the rates are stacked up to suit their operation, we were to fly at reduced rpm so they could pay less for fuel while charging out more hours flight time and overhauling the engines less often (tacho time is less). I know that effectively got us a PPL at lower cost along with bumping our bookings whenever a tourist wanted the plane for scenic - depends what price you put on your time and if those logged hours are effective value for the money. The other factor is you dont get to take a rental anywhere or anytime you like, it has to be booked and if you get stranded with weather etc. you might be paying twice for someone else to get it back. To go on holiday the economics of hiring self fly dont stack up but if you already own it then the actual cost of making that trip is only the cost of fuel and oil and landing / ATC charges all the other costs are going to happen whether you fly that trip or not. I chose an older Cessna after doing due diligence on the type, visiting more than 2 mtce shops for advice on the pros and cons, Lycoming issues vs. Continental. Avoided a syndicate because I wanted full control over useage and no arguments over mtce standards. I was able to save a lot of costs by doing simple items like corrosion control under advice / supervision, often they would let me use their workshop facilities while I was there for the annual no self respecting LAME would rather do this work if you will its like the garage sign that reads "repairs $100 / hr while you watch $120 / hr while you help $140 / hr" They had told me an annual on a Cessna would take about 9 hrs vs. 11 or 12 for Cherokee as the removal for inspection work is more. It cost less if I opened up all the inspection panels for them also it doesnt cost any more to maintain 4 seater vs. 2 the inspection items are equally tedious. Best of luck choosing, either way I dont regret getting into flying. Its an observation that pilots often prefer the type of plane they trained most in, I started with C172 and preferred high wing ever since. Mate was a Piper man, so much hassle getting in & out but it got us there regardless.

best value Flightline 760 https://www.aircraftspruce.com/catalog/avpages/vhfcomtranceiver.php Unless you are fitting an ADSB Trig Xponder, then it might be better to get the trig VHF at the same time

Youre right it was probably the Daihatsu 360Max https://en.wikipedia.org/wiki/Daihatsu_Fellow_Max#550cc_era At the time there were also Suzuki Fronte and the original Jimny cruising the streets with the rin tin tin noise

I liked the concept of using kerosine instead of petrol for safety and cost - for something like a generator or boat there are advantages, I had a colleague literally blown out of his boat due to the inboard gasoline engine - probably a mtce issue but there you go. When I bought my first new generator, the catalogue had models with the big kero tank and the small gasoline starting tank, but this version not available in NZ. Mate was studying at Med school and with not much money, used to make the 1000km trip home in holidays with the trusty 2 stroke Daihatsu Charade, no modifications, start on petrol, go to the servo and fill up around the corner "home heating fuel" thats not even real kero - put enough in to run out before the ferry terminal, put a bit of petrol in so the car would make it on and off the ferry, back on the boiler fuel for the rest of the trip. And our farm motorbikes we put a 1/16" aluminium gasket under the head and ran white spirits for them. The tax in NZ is more than 100% for petrol, whether you use it in the plane or boat there is no refund for recreational or offroad use. I get my kero from the JetA pump at the airport, so it costs about the same as Diesel. I was using rather a lot in JetCar, wouldnt buy it at the hardware store when youre burning 1L / min. The reality is that petrol engines are so lightweight and efficient - skyactive X etc. that its not feasable to use the Diesel / kero equivalent in aero applications the extra weight is too much. There are some Smartcar Diesels that might be possible conversions. Getting the engine is difficult as they were not sold here. My last 2 work cars are Diesel and I really like them, currently Ford Escape it runs smooth, not endlessly changing gears and barely any noise. Pity that for reasons not related to the engine itself, they have gone out of favour. I see merit in Diesel - electric series hybrid with a small battery for boost / regen on aircraft.

You really need to check how the probes are attatched as well. If they are the old way, a ring around a randomly chosen spark plug, there is huge margin for error. The new Jabiru method not much better, a ring lug attached to a screw on the surface of the head. Proper way is thermocouple junction entirely "down the hole", immersed in heat conducting paste, covered over by silicone RTV or similar. If not an instrumentation error, then maybe you need to increase the baffles in the air ducts per jab installation instructions.

With Jabirus, failure of the sender has been common for years. Its not to do with the orifice which is already part of the sender. Its caused by the improper location of the sender onto an oil port upstream of the oil cooler where pressure pulsations are high however the actual oil pressure to the gallery and mains (where the reading matters) is lower. If you dont want to keep replacing senders every 150 hrs then shift it to the other port available on the front of the crankcase. see where the windings are worn out due to consant movement. when the wiper fails open the gauge will read full scale

Mine is a CZAW built kit, has threaded rods for the flaperon and nosegear steering parts. The plans for rods 2J and 7C1-6 are - solid threaded steel rod 5/16" x 24 rod ends are CW5-12 with jam nuts AN316-5R, except the two upper 7C1-6 rod ends get a quick disconnect (Superior linkage products SS 103) It always seemed a heavy way to do it but as the kit is designed to be built at home I'm satisfied with the tradeoff.

Can the LiFePo4 battery system tolerate the jabiru / Kubota pulse type rectifier / regulator? The behaviour you are describing is typical of an overvoltage cutout system operating when it thinks the 20V or 40V spikes put out by the Jabiru dynamo (PMA) occur, which will be most prominent after the battery has been topped off from the starting and ground idle discharge period. With a standard Jabiru wiring and lead acid battery this is not a problem. The Lithium Ion battery usually has management circuitry built in. I think Powermate and / or the regulators sold by B+C Specialty for the homebuilt market are linear regulators and might be better suited. The later Jabiru PMA is rewound with double the output voltage of the original, in an effort to please the US market where they hang lots of extra avionics and the charging system doesnt work enough at idle. I dont think that is a good idea. Ralph

The new interpretation / diisertation is not specific to Rotax, seems that Rotax are more affected because they have calendar items and times which most others dont. It could be very bad for 582 / 503 engines in service....isnt there a crank inspection every 300 hrs? The Microlight organisations here (at least 2 of the 3) are in discussions about it RAANZ info posted here http://raanz.org.nz/wiki/pmwiki.php?n=Main.Whatsnew Dont know what SAC are doing exactly BTW the flight permit document also specifies a new permit must be raised whenever an engine or propeller is different to the one listed. Seems they use the same form that was written for multi engine / CSU prop certified aircraft. Costs about $300. Not fun if you want to swap to climb prop for a weekend of bush flying..

Mine gets better climb rate and engine cooling with flap set. I use 50kts and a climb prop running at 3200 - 3300 rpm. strut fairings made a big difference to climb rate too. yes nothing can fix a hot day with full load, in that situation I plan on a climb rate around 200 - 300 fpm, its not pleasant and even a Rotax 2 stroke would probably do better. Ralph

I've often suggested a look at the Flightline 760 (ACS) as it seems to have similar features to Microair or Xcom at a lower price point. There are few of them about so quality is unknown - the first one I've seen was in an aircraft last week and they had no issues with it. Trig has a good record here. Ralph

The standard setup has to be rigged with enough slack in the elevator cables to allow full right aileron deflection and then the left deflection makes the cables loose. I think the rigging instructions are deliberately vague because the simple to construct design has these issues. Another not obvious rigging situation is the rudder tensions, which need setting with the nose unloaded because the cables go slack with nose strut compression. Incidentally my initial CAA inspector was puzzled with the tightness of the cables and thought it might be due to the plane being rigged in the Czech winter and now its summer in NZ and aluminium fuse has expanded....I still laugh about this. Rather than second - guess the design I just call it a backup feature that holds the rudder firmly on - anyone familiar with 701 Hstab and rudder attachments will know I'm serious about this. If you are at the fabrication stage I'd do the mod to not have the elevator yoke rotating on an offset to the aileron tube. I've been flying mine since 2004 and the remedy to reduce the aileron bias (to the left) was to alter the position and tension of the bungee inside rear fuselage so it pulls the upper cable to the right. this by no means cures the problem just makes flying less tiresome - it holds a bit of trim tension the way that centralises the stick. Ralph

I'm a bit confused about the "Jabiru return system". Apart from mate with SK who would empty the catch container to the sump as part of preflight checks. If done with a designed oil seperator, theres probably nothing bad about a return system, did Camit offer one? My 2200 would fill 500ml catch bottle about every 15 hours. A bit less often now with new rings @ 500 hrs. I have the original dipstick before Jab "fixed" the issue of blowby by shifting the full and empty marks down about 1/2" I'd rather keep the level up at least the underbelly of my plane is corrosion treated daily. I just had another pail of oil delivered, 19L cost $299. Maybe I should reconsider.

a long time ago I bought Headsets inc. (link in Downunder post) ANR kits and fitted them to my existing headset. They work well and still in use, but I run them on aircraft power rather than 9V battery

For a well known brand its normal. "exhaust valve opens 65 deg BBC." For a Jabiru, probably not. they usually leak throughout.

I put one on my 2200 to measure the prop load vs rpm temporarily. You just remove a small screw from the middle of a port on the carb underside and place the hose there. It doesnt matter what type of gauge you use if you convert the units of scale. I just borrowed a gauge from a set of 4 carb balancing ones from a m/cycle supplier, these come with a damping valve fitted so you can remove the chatter, depending on what you are trying to use it for. they are compound gauges, not sure why for m/cycle tuning because bikes dont usually have turbos. Bought the gauges because the cars i was working on needed 4 carbs balanced - Honda S600 & H1300 Coupe

Bruce, If you are looking at mixture issues and the behaviour of EGT at full power, a lot of this has been covered by various Jab servvice letters, Jabbachat and finally the "manuals" My engine was a few hundred prior to the 'economy running kit' which after about 5 reissues became the production carb jetting setup today. Note that it only applies to the correct type of prop loading conditions. I spent lots of time swapping / redrilling jets as starting with OEM kit #1 it needed constant updating by factory SB. In the end I got the correct response which is a higher EGT at cruise power 2900 - 3100 rpm and a reduction of EGT from 3100 - 3300 rpm. This is very similar to the behaviour of the MS carb / O-200 my C150 had. Other than prop loading, there are a couple of things that might affect your response. The way the carb float vent line is vented (must be into the air intake after the air filter) Some jab engines were / are supplied with larger float valve seat diameter. There are different float valve spring tensions available There is different fuel pump spring tensions there is different fuel pump plunger lengths They changed the cam profiles they retarded the timing on 3300's

My engine (2003) and those up to about 2010 came with red HT leads which are plastic core carbon type. To be fair, the old automotive carbon leads were much less reliable than Jabs (leads) as the core seemed to be cotton wrapped carbon which would crumble out. Jabiru switched to the black leads which are believed to be inductive wire type - I havent had the opportunity to test them. I use the Bosch ferrite core helical wire inductive leads from SCA. The wire is SS and has a resistance proprtional to length but generally less than the original carbon plastic core Jab OEM red ones. Cars use these leads together with R spark plugs, but that cant be compared to the Jab setup which uses lawnmower parts mixed with a car distributor (variable spark gap right there) so I tested the voltages and spark with different leads, plugs and gaps first. If you wanted low resistance you can buy Magnecore or similar. care needs to be taken if reterminating these leads, different plug caps use diferent ways to spike the conductor. I dont know what these quotes about silicon leads are all about. Silicone leads refers to the outer insulation covering, nothing to do with the conductor.

Pity NGK dont make their shielded plugs BS-6E and BPS-6E in 12mm. Aircraft shielded leads are constructed with a helical wound wire core which is good RF supression without the carbon which hasnt been used in cars for 30 years and Jabirus for the last 10 or so....

I have been on R plugs in my 2200 for 12 yrs - ever since replacing the original resistor carbon leads with the inductor type. This was done to reduce the radio interference that Jabs are so well known for. Extensive testing with lab equipment showed no change to the loading or stress on the coil packs or any other part of the system. The coils are for Honda lawnmower engines and have a resistor plug or resistor integrated cap depending on market. I never clean the plugs, just replace at 200 hrs. They are gapped to the Jab setting as these are standard plugs. This would more than make up for the perceived effect of the resistor. In reality the resistor doesnt lower any voltage to the electrode because there is no current flowing at the time - see scsirob post If I were to fit Iridium, I would leave the gap at the wider setting its because the spark threshold voltage is lower to break across a pointy end. Next plug change I might get Iridium, but the cost benefit is not great if I'm getting 200hrs on regular plugs

Pilot dentist buddy X-Rayed one. What you see is the film taped to a window, hanging in the conventional way. The guts of the thing appear to be the connector centre shaft coming down, soldered to a flat perforated pice of metal, roughly the shape of the outer moulding. Radio is a black art, what we see doesnt allways look plausible. GPS patch antennae are another mystery.

this is what the dentist saw

No, they are more robust and expensive. The cheapest version of stick and ball are prone to breaking when washing the plane.

only new (gen4) for the Jabiru, but postpone this decision until there is an established track record. you could safely choose a timex 912 and just overhaul the gearbox, they have a good record and flight schools often renew them rather than overhaul. the D-motor is my personal 1st choice, it comes down to price and that depends on the country. In my case, the existing engine mounts are for Jabiru / D-motor / ULpower and that represents a big difference. The ring mount for the 912 is pricey but essential and adds to the cost.