Oh, and there's starting a Gipsy on a VERY cold morning. I was trying to do this once and the engine wasn't having it. The on-airfield aircraft engineers were open that morning and they couldn't start it using the usual methods either, so I was instructed to get in while two hefty lads lifted the tail to the level attitude.
The chief engineer then did the tickle, suck in, called for 'CONTACT', and swung it. It started first swing.
"Usually when you suck-in you are sucking in vapour from the pool of fuel at the aft (lower) end of the inlet manifold", he explained. "When the wx is VERY cold the fuel doesn't vapourise as readily and probably only the back cylinder gets a whiff. Hold the tail up so the manifold is level and so is the pool of fuel, and they all get some".
Well, it certainly worked!