Vev

Yes Nev ... same wing on the 230 & 430 too

Turbo, You sound angry … you really need to listen to Nev… he has already given you the secret Grasshopper! Besides how much runway do you guys need over at Tooradin to land a little old 170 when your white line is wider than the Tyabb runway? Think Zen Turbo, and all will be yours (including the 170). :thumb_up: Cheers Jack

Spot on Nev … just remain ahead of the ac, use coordinated gentle inputs, be patient on landings as you hold off and you can make the old Jab sing like a bird. Get behind the curve, over input and over correct and you will spend your day in frustration ballooning on landings and doing go-arounds. Cheers Jack

G’day David, You are correct to say that limited exposure when opening containers will minimise octane depletion through evaporation and over a short period it will be very small. But that’s not to say you can store fuel indefinitely, as oxidation will take place and over time will impact many of the good characteristics of fuels including octane depletion through limited exposure if stored long enough. Over the years I have seen many well sealed containers (20lt and 205lt drums) and fuel tanks fall of sludge, albeit these have been over prolonged periods and exposed to high temperature variations…. Never the less it does happen. In terms Mogas containing of ethanol; you need to apply much the same storage considerations as any other fuels but it does tend to have heightened hydroscopic characteristic and can absorb moister from the air; thereby increasing both free and dissolved water into the fuels. This can cause problems in terms of corrosion, accelerated oxidation and burn characteristics. Personally, and for what it’s worth, I’m not a fan of ethanol and go out of my way not to use it… I know other will disagree with my position on ethanol but that’s entirely my point of view. Cheers Jack

Hi Pete, Basically the ULP will act as a diluent and retard the tempo of the lead depositations … additionally, the combustion chamber will also benefit from the detergent additives in the ULP and help slow the build up but it won’t stop it, although you will see slightly lower concentrations over all. Hope that helps Cheers Jack

Hi Pete, Generally speaking, the storage and handling of fuels does deplete octane during the logistics process. However the claimed octane by the major oil companies is always understated…. a 98 RON octane is usually 99 when you buy it from the pump. In my view there isn’t too much to be concerned about, other than follow good handling and storage processes. If you blend in Avgas you do get a slow down in octane depletion on Mogas as Avgas has a much lower volatile product (iso-octane) as its base hydrocarbon chemical make up… additionally you will get an expediential octane bump as the lead in the avgas will react with the Mogas to increase octane. Cheers Jack

Continuing to maintain a process for no better reason than because “it has always been done that way” or "they wont let us" is a nonsense to me when it come to safety improvements…. I think the current aviation weather forecasting services will make a wonderful wall decoration for The Flat Earth Society club rooms. Lets move on and use some common sense. Cheers Jack

John B … thankyou for the direction. I will be writing to my RAA board members and encourage others to do the same if they believe we should be officially allowed to use plain language weather reports for flight planning. Cheers Jack

Ian, I congratulate and thank you for providing this free service to all us. It’s a very useful and practical site … I have shared your site with a number of friends from all walks of aviation with decades of flying experience and 1000’s of hours. I have yet to come across a pilot that hasn’t thought your site as being a fabulous service and a potential life saver. Cheers Jack

Hi John Brandon, Like you, I agree Ian’s site is excellent and I use it weekly... I also appreciate your reminder of our obligations under CAR 120. Personally I think Ian Borg’s Avmet site is more likely to save a life by reducing the probability of misreading an official weather report from the current official system. Whilst I have no idea what it would take, but it would be a wonderful step forward in the interest of safety, if Recreational Aviation Aust could seek dispensation to use simplified plain language weather reports. The RAA and others have done a great job over the years in reducing complexity and making flying safer through a common sense approach, I see this issue as a potential opportunity to do more. I believe there is a reasonable case to challenge the regulators on weather report formats and would like to see the RAA consider leading the way. Regards Jack

Thanks DC10... I looked up the part number you have supplied and its off a bunch of early Honda cars. Cheers Jack

Thx Harthy, I would agree with you in the main but there are some consumable parts I feel ok about not buying from the OEM ... to name a few: spark plugs, HT leads, oil and air filters, lubricants, most o-rings, batteries, rotor buttons and distributor caps. Would I buy a set of conrods or other major engine components from an after market supplier, I think not! Its not always the money either, it's more about the access to parts when you need them and not having to run my own store of bits or wait a week to get them. Cheers Jack

Can any one tell me repco/Super Cheap part numbers for Jab 2200 engine Distributor Cap and Rotor Button? I think the rotor button is off the VP Commodore but not sure about the Distributor Cap ... does anyone know for sure? Cheers Jack

Quote Now, the problem often arises where brakes don't perform to specs and overwhelmingly the most common cause of this is brake fluid that is not doing it's job and this is governed by age, type, quality and use. Brake fluid absorbs moisture and for every application of your brakes, degrades in performance. Hard frequent use will effectively 'wear' out your brake fluid. --------------- Hi Relfy, Can you explain what happens to brake fluid during "hard frequent" braking that "wears out" brake fluid? Cheers Jack

Andy, These guys make bakes for Jabs including a differential braking set up if you want a Rolls-Royce solution. Matco Mfg | Welcome Cheers Jack

good one Peter Cheers Jack

A mate of mine (Ken Ingersoll) is a Corvair expert and has been importing these engines from the US since the mid 60’s were he made adaption kit for VW conversions. Over the past 2 years he has been developing an aero version (he calls it a Corvaero) for his Long-Ezi. He has done a great job on the engine and has sorted out all of the problems one usually hears about with Corvair aero engines. He has used the 145 cubic inch engine being the smaller of the two available (the other being 164 inch) and has mounted the alternator and starter to the rear; this has pushed the c of g back and has reduced the frontal area of the engine. He has also developed a very robust PSRU (prop speed reduction unit), as the direct drive engines rev too hard for an efficient prop speed and end up with a narrow power band to operate when you pull the power back. He says that his PSRU allows the engine to operate at optimum power setting and has a broader power range and a more progressive power curve for different rev settings. He says the engine can develop a torque value simular to a 0320 of up to 150hp and only weighs 250 lbs ish. He has also designed a heated manifold and is running an Ellison TBI and hasn’t experience any carby icing issues in his testing date. He has one of his engines on a test stand with a Bolly 3 blade prop and is running test on it now before he mounts it into his aircraft. I spoke to Ken this morning and he is happy to chat to anyone that wants to know more about Corvair engines.... He's down at Baxter in Victoria. If you want to PM me I can send you his contact details. Cheers Jack

Bushpilot quote - "The J120, regardless of category, is 430 kg - same as the old ST models." Chris, Am I not getting a point you are making? Are you sure about the 120 MTOW ... I thought it was 500kgs? Cheers Jack

Bush Pilot, I always hand pull through to make sure all feels normal and then crank with mags off and look for the oil press needle to lift off the stop a little before running the engine. I'm sure it helps reduce wear at start up. Spacewalker, what viscosity oil where you running in that engine when you ran your pressure tests? Cheers Jack

Tomo, Re Ether and problems with using it in aero engines. These commercial available sprays are usually made up of 60% Mogas, 30% Diethyl Ether and 10% Ethanol … give or take a few %. Basically these are designed to increase the cetane number in diesel application, which is gabout helping start a cold engine where the fuel quality is low and in very cold climates.. In Oz we have high quality diesel and it doesn’t really get that cold, therefore it’s a little more difficult to make an argument to use these products. When you use this stuff in an aero engine it has the same effect of reducing the octane and it speeds up the flame burn and can cause detonation .. Not a good thing for any engine any time. The chemistry can also impact on seals and other components and can cause plasticisation (make thngs go soft) of seals, o rings etc. Hope this helps. Cheers Jack

I can’t say I love the Bing … the whole carby feels like a compromise of lesser evils and one tends to run the Bing mostly too rich to keep temps down across the working load range ... this is the only way to maintain acceptable levels on the hottest cylinder. The idea of keeping things simple (no electronics) yet provide the pilot with the opportunity to adjust the mixture in flight is very appealing to me. It would be nice to be able to keep things rich and cool in climb and then adjust from your EGT readings to get set up for optimal cruise mixtures… currently with the Bing you end up with it too rich everywhere less you run the risk of burning a valve and cooking your top end. I have had a look at the XXXXX, which looks like a copy of the Ellison TBI other than the regulator is remote, where the Ellison has the reg as an integrated part of the body. They both use a fuel bar which has many very small holes drilled along the delivery fuel tube (sometimes called a fuel bar) that becomes progressively exposed as a flat slide opens… the slide process is simular to a motorcycle slide on a 2 stroke carby. The fuel delivery volume is determined by the fuel bar position (which is controlled by rotating it ) and the angle of attack of the air passing through the throttle body…. By remotely (from the cockpit) rotating the fuel bar you change the mixture and set things up just where you want. The slide controls the volume of air entering the throttle body as well as exposing more of the delivery bar as it slides up. They both have a conventional idle circuit but they do need to be primed to get them to come to life as there is no fuel bowl to store fuel. I guess this is one of the real down sides of the TBI is one could over prime and end up with a lot of fuel over flow and increase the risk of fire at start up. Intuitively (I’m guessing) the XXXXX approach may be slightly better at creating a more homogenous fuel/air distribution in the atomisation phase and therefore a reduction in the variations in CHT/EGT temps across the cylinders owing to a more even air/fuel mix… may be someone out there can verify or dismiss this my assumptions??? Personally I am still sitting on the fence and waiting to hear more reports from users and get some hard facts regarding performance before I dump the Bing…. However there are a lot of these out there, just not sure how many on Jabs and how they are going? Cheers Jack

Agree Tomo ... as a general rule it's aways best to bend as close to the time of use and if you have to store any fuels do so in full high quality containers in a cool place for short preiods. Old saying ... "There's no fuel like new fuel and old fuel is like no fuel". Cheers Jack

There are several ways for fuels to go “off” however in this context I think people are concerned about octane depletion when using Mogas compared to Avgas. In very simple terms, Avgas has lower volatility and the components that give it its octane doesn’t evaporate off very easily … whereas Mogas has lighter more volatile components which evaporates more quickly thereby depleting the key octane boosting hydrocarbons in the process. High quality well sealed container kept away from heat will slow the speed of octane depletion in Mogas. Unfortunately aircraft fuel tanks aren’t the ideal container … best not to store for too long in your aircraft.... fresh is best. Cheers Jack

Thx DJP, Good stuff Cheers Jack

G'day Matt, Very well said and written ... In my mind, there was never a monument built to a critic. Lets all hope your letter strikes a cord of unification for all that want to fly. Cheers Jack