wideblueyonder

"familiar even resistance"??? Yikes! There should only be a healthy bounce between compressions hot or cold. Definitely do not fly it in its current state. Sounds from your description that there is tightness in the engine and it needs further investigation by someone knowledgable and experienced in these matters, specifically Jab engines. Not just another jab owner, but someone who has considerable expert maintenance experience with repairing and overhauling jab engines. Well done on raising your issue for advice! Wby

3 cylinders are down on prop pull through.... You need to be a bit more specific and give us more details. If it was when stone cold and not used for a while, then un-even compressions is not uncommon for a lot of engines. If it was after a monthly run-up (preventative maintenance) then you would know that everything is close to operating temperatures, lubricated and valve and ring contact surfaces are not contaminated with surface corrosion. Give the engine a quick ground run first and check your compressions again. Do not over-do the ground run, as valve seats have been known to come adrift from overheating. I'm confident that your compressions will feel normal enough for a flight and be completely normal after your flight. Wby.

Excellent tutorial here: https://forums.sailboatowners.com/index.php?attachments/repair-of-yanmar-tach-updated-pdf.59966/ how to rectify your failing VDO hour meter display. The problem stems from a failing of the silicone rubber used during manufacture to seal the transparent conductive tracks on the printed circuit board where the ribbon connects to the board. Remove all of the crumbling sealant with a sharpened toothpick and small brush and have your hour display reading reliably again. wby.

Hi Mac, Welcome to the forum and to the wonderful world of recreational aviation! Some important things to consider when deciding what to buy: - Be led by advise, practicality and function, rather than what looks cute. - Consider as a very high priority an enclosed airplane over an open design when planning on flying in Tasmania. Our best flying is during the colder months and having to dress like an Eskimo and still freezing is not fun. ( even harder now as we are no longer 'spring chickens') - Nev is spot on. Fabric can be tested very easily and regardless of condition, usually makes for a more affordable 'first' aeroplane. - As I mentioned in a pm (personal message) there is a very nice low hour Thruster for sale in Tas. As it is already 'over the pond' it's asking price is even more attractive as it won't have to be flown/ trailered home (trailer, fuel, time, Spirit of Tasmania costs, booking availability this time of year etc. - So if you buy a single place aeroplane, you will have your investment sitting in a hangar somewhere while you pay dual training rates to learn to fly someone-else's aeroplane. I am more than happy to take you through the course of training for your pilots certificate in my Jabiru, but you will still need to fly a further minimum amount of time for any endorsements you will need such as Tailwheel, twostroke etc. - Finding somewhere to park and fly your plane near where you live in southern Tas is going to take some effort. There are folding wing designs that you can trailer and keep at home. I owned a Gazelle and kept it in a fully enclosed trailer. Best ever. - It is most unlikely you will ever intentionaly land on a sealed runway here in Tas. Your choice of aeroplane should reflect that. What is more important than speed, transponders and artificial horizons, is the ability to safely operate from paddocks. So, bigger wheels, effective brakes, softer suspension, propeller clearance, slower touch-down speed is very high on the desirable list. - If you buy a two seater (and there are lots for sale), you can't learn to fly in it unless it is 25 or 24 registered (factory built). You can learn to fly in a 19 registered 2 seat plane, but only if you built it. You can do your cross-country training in a 19 registered plane, as the flying is not for a certificate, but for an endorsment. - Get at least enough flying training under your belt to be at the stage where you can takeoff and land unassisted. This will give you a very good idea of what kind of flying you wish to persue. After a life-time of romancing of flying and aviation in general, you may have formed a mental vision of a flying style that may not be reflected in reality. - Talk to the schools who have been around for a while. They probably earnt their living in the early days from flying Thrusters and Drifters. (Fabric, twostroke, factory built= affordable.) and will be able to give you first hand experience regarding costs, maintenance etc. Good luck, hope this helps WBY

Rotax is available in both four stroke and two stroke. I'd be astounded if those Rotax failure statistics referred to the 912 series 4 stroke. The 4 stroke Rotax should be compared with Jabiru for reliability, to even the playing field. I have flown a Zenith 650 powered by a 100hp continental. Goes well, ultra reliable. Gets off and cruises adequately, even with two persons onboard and sounds tough. For the 100 hp produced, it is heavy when competed to other power plants that are also suited to this airframe. A current series (gen4) 6 cylinder jabiru would make it a much more lively performer for a similar fuel burn of 95 or 98 RON auto fuel. Ron is a "research octane number" not to be confused with "octane" which is an actual power value or the resistance of the sample fuel to detonate ( in simple terms). It does not specifically require avgas because it is not a classic slow turning engine where detonation may occur on low octane fuels at low rpm under load. I use 95 ron with no problems in both of my 2.2 four cylinder jabiru motors. Fresh fuel is the ticket. Metal jerry cans for purchace and pumped into the plane through an apropriate particle and water separating filter is the go. The volatile elements of unleaded ( that replaced tetra ethyl lead) is the first thing to evaporate from a fuel container if given the chance, leaving you with expensive 91 Ron or less, where detonation is almost guaranteed in a Jabiru motor. A Rotax 912S (100hp) is also very nice, but as others have indicated, expensive. But you do get a reduction gearbox so you can potentially swing a bigger diameter prop a bit slower than that of a jabiru, giving better takeoff and climb performance ( through efficiency). Rotax do not suffer from heat soak of the cylinder heads. ( leading to valve seats becoming loose)The engineers at Bombardier thought of that and designed the heads to be liquid cooled making them marginally quieter as an added benefit. Forget the 80 hp for the '650. Very reliable, just not enough horses for the '650 in my experience. I operated an 80 hp Rotax in a flying school plane for over 800 hours and the only maintenance I had to attend to other than the regular oil and filter changes, was to replace the oil pressure sending unit ($24.00 from Repco). Superb engineering, quality, time proven materials, smaller capacity engine turning a bigger diameter propeller through a propeller speed reduction gearbox is a modern solution and good engineering practice. Just my AUS$0.02 worth