Model Forum / Radio Controlled / Helicopters / June 2004

> Here's one for all you engine gurus.
>
> My mate Rick has cooked his TT 50:-(
>
> It's about three months old, (about 20 tanks) has been running on Prosynth
> 5% nitro and up until last weekend was fine. Sunday it sounded a bit harsh
> and due to operator error, spat out a glow plug at some altitude, not a

> of height, just enough to make Rick glad he'd been practicing autos on the
> sim! (Reflex XLR, awesome graphics!).
>
> A new plug was screwed in, this time tightly, and all seemed to be well.
> Yesterday he went out on his own and after a short while phoned me to say
> he'd had an impact with the hard bit at the bottom of the sky, bad enough,
> all the usual damage, but when he tried to turn the engine over by hand,

> wouldn't. The backplate came off and there was the con-rod in two bits. NO
> sign of overheating, nice and clean inside. At the time the engine was
> running at more than three turns on the main needle and producing smoke.

> The other factor was that he'd changed to Prosynth 10% and had mixed half

> gallon of 10% with the remains of the 5%, thus making approximately 7.5%
> Nitro mix.

> The motor came from Cyber and they have suggested by mail it was probably
> due to a lean run........;-)

> Any thoughts......