For your car

There are many myths among pilots regarding engines. I hear people saying “maybe the bearings are broken” – well the engine starts just as easily with bad bearings so trust me it’s not that. People who blame bearings often do not fly enough to break them anyway, although admittedly you can do it in one flight if you are reckless enough. But this I know – when a bearing is broken you will hear it, and feel it when turning it over.

Cylinder peel is another myth, i.e. the peeling is real enough but the manufacturing problem people blame is highly unlikely. Bad fuel and running the engine piping hot is a more likely explanation. Pitts style mufflers and tiny canister mufflers are probably to blame, as are tightly cowled engine installations. Engines need to get the hot exhaust out, it they don’t they overheat. Simple enough, so why would you fit a smaller muffler than the original, and blame the manufacturer when your cylinder goes flaking on you?

A very common myth about certain makes of engines is that bits of metal shavings can be found inside them (most makes that are made in China have this reputation). Personally, I have never looked and will never look for stuff inside and engine, because chances are the factory that made them is a lot cleaner than your workshop. I believe if you find metal inside your engine it’s because you messed up disassembling it. Leave it alone unless you are an engine mechanic.

In fact, the only thing that comes to mind that actually happens every once in a while is a broken piston ring. If stored with a lot of castor oil inside for a long period the ring will get stuck and break once you try and start if at the beginning of the season. It’s highly unlikely that any other sort of damage is the cause of your engine not wanting to start.

Let me explain what actually happens when it won’t start or dies:

Fuel: The engine needs a proper mixture of fuel and air to start. This means that if it doesn’t start, it has either too much or too little of one or the other. People are usually not aware that the engine is being flooded and this is easily overlooked because there is usually not much indication of it until the engine locks up. This happens to everyone, even pros struggle with this sometimes. But you can spot the clueless pilot easily: he’s the one blaming the engine maker, or claiming the bearings are broken. I’ve also seen people grinding away with starters at engines that are bone dry. Hey, did ya open the needle valve dude? Connect the fuel line wrong, plugging the vent line to the carb? I see it ALL THE TIME. Something I do every now and again is try to start with no air… meaning I’ve forgot the throttle cut-off switch from the flight before. Duh. But try and learn from it, and don’t blame the engine.

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