Not sure if I'm dreaming or not so need some advice.

I have a model helicopter project in mind. It will be powered by the new OS GT15HZ gas engine when it becomes available:

http://www.os-engines.co.jp/english/...newsgt15_e.pdf

For my application, I really want to run this engine "backwards" i.e. have the crank turning clockwise when viewed from the front rather than the conventional anti-clockwise direction.

Is it just a matter of repositioning the timing magnet to the equivalent location before TDC and spinning the engine clockwise to start?

Any lessons someone can help me learn cheaply?

Good advice appreciated.

Unfortunately not. The intake is timed on the crank, so unless you had a way of rotating the carb 90º to the side of the silencer, like on Enyas, or a rear carb intake like the GT33, on this engine, you're out of luck.

Are you thinking of a Chinook to model?

I'm intending to put the GT15HZ into a Henseleit TDR airframe.

Thanks for the quick reply.

In looking at the pics of the engine, it cannot be run in reverse, unless you have a reverse rotation crankshaft made for it. I doubt OS will make one too, but you never know. The crankcase is a one piece design, so you cannot rotate the carb 90 degrees to set it up to run in reverse. Of course you'll have to retime the ignition for reverse rotation too.

Originally Posted by earlwb

In looking at the pics of the engine, it cannot be run in reverse, unless you have a reverse rotation crankshaft made for it. I doubt OS will make one too, but you never know. The crankcase is a one piece design, so you cannot rotate the carb 90 degrees to set it up to run in reverse. Of course you'll have to retime the ignition for reverse rotation too.

Indeed. Some makes did have clockwise crankshafts. Like Webra. I used one of these on a Marutaka P-38 in the 70'ies. Like earl says, with an engine that has a detachable front one can rotate it to have clockwise running.