Servicing and Overhaul
I have a lifetime of experience of tinkering, fiddling, experimenting, building and yes actually doing real qualified trade work as well. Aviation and motorcycles are the fun stuff, hydraulics, diesel, petrol, gearboxes are fascinating. Plus a little too much time doing composite work, painting, welding and machining when you just can't go and buy something.
Workshop
Our workshop is conveniently located at YGAW, Gawler Airfield for normal people. Located only 1153 nm from Perth and 803 nm from Brisbane. Feel free to stop by for a chat and a coffee and if we have time actually do a little work.
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The street address is,
Hangar M5
1 Ward Belt Road
Gawler Belt
5118 South Australia
But flying in is just so much of a cool thing to do however.
The things that you find when working on other people's aircraft.
I am not going to mention Anthony's name as I don't want to embarrass the man. But this find in the back of a Jabiru 170 whilst changing the fuel filter just had to cop a photograph.
Just some of the things that go wrong
This picture shows some of the oddball problems that we come up against. The only sign of trouble was the differential leakdown test failed on one cylinder. It was definitely a valve problem instead of blowby past the rings. When the valves were removed from the head, extreme wear was noted on the valve stem collet grooves. It is almost undetectable from the outside, but if it had been allowed to continue the engine would have dropped a valve with the expected catastrophic results.
Heat, the engine killer.
This is a symptom that unfortunately I see from time to time. Low cylinder compression caused by excessive blowby past the piston rings. If you look closely below the top piston ring you can see how the ring groove has started to 'move' downwards allowing the top ring to flop around and the second ring to be jammed tight in the groove.
You've seen the symptom, now here is the cause.
The picture above of the damaged piston was caused by excessive heat. What caused it was the wear in the main bearings causing a lack of oil supply to the gudgeon pin and the underside of the piston. Oil acts as a lubricant obviously and also just as importantly as a coolant. The act of the oil spraying against the various bits and pieces on the inside of the engine draws heat away, where it is drawn away by the air flowing past the engine and oil cooler.
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Unfortunately, this heat is localised. It generally won't show on the cylinder heat temperature gauge. The CHT gauge measures the heat of the cylinder head, however the heat of the combustion process heats up everything, head, cylinder and piston. The piston gets rid of it's heat via the rings and piston sides against the cylinder wall AND the oil splashing around underneath it. Not enough oil, well you can see the results. It doesn't happen straight away, it takes a little time to develop. Run a 2 stroke engine on a weak oil mixture and lean fuel mix at full throttle you don't have to wait very long for some excitement to happen. But on a four stroke, where the oil is there, but not enough it takes a little longer.
The things that you just gotta do...
This is what I had to contend with the last time that Rhonda the Honda and I travelled up to Jabiru Aircraft in Bundaberg. I was originially going to fly up, but the cyclone and extreme heavy rain put that idea to bed pretty quickly. As dumb as it sounds, travelling up by motorbike was actually the sensible idea. I would not have made it if I just driven up. I had no idea on that Wednesday just how much water was going to fall out of the sky west of the Great Dividing Range and Brisbane. I got into Bundaberg very late that night, I dried off under a hot shower and staggered into bed after a very eventful and long day.
