ST G51 mounting orientation

Does the G51 give a good run if it's mounted inverted?
Or, will I get a burp on a tight corner?
Is the G51 happier mounted profile style?

Any experience would be welcome

Michael McMahon

I have three of the T&L ST51. These engines have been used in several different types of airplanes and all had inverted engines. The ST's ran fine and I did not experience and running problems at all.
However when starting the engine when it is cold you will need to flip her over on her back to make starting easier. When starting these engines inverted sometimes there is a tendency to flood the engine. I do not know why but it happens.
One thing that helped me the most when I flew by my self, was to develop a method to start these engines inverted.

#1. Fill the tank with fuel.
#2. Hook up the stooge.
#3. Flip the prop about 7 or 8 times until you feel the fuel start to lubricate the engine.
#4. Apply the glow driver and try to crank the engine. It should come to life in about three flips.
#5 At no time should you put your finger over the venturi and flip the prop, this will indeed flood the engine.

I have found this to be true with all of my Super Tiger engines.

Be careful and good flying
Mike Clark

My inverted out-of-the-box standard G51 is a delight. Cold starts need it to be primed until it's just starting to sound wet and no more. Hot starts need a single prime which is more to get fuel from the tank to the needle valve. I get a first flick start virtually every time and run it in a constant 4 stroke through the entire pattern and certainly no burbs whatsoever. Mine would only run like this using 25% all castor and zero nitro, with 20% castor the revs were all over the place during the flight. Fuel consumption is amazingly good at 10cc/minute which is why I suspect it needed the 25% oil.

ST 51's run great inverted. been using them stock for about 10 years now, over 1000 flights on one alone. The key is in the setup. Mount your fueltank 1/16 to 1/8 inch above the needle valve when looking at it from the top. I prop it with an old 12-5 powerprop at 9100-9300 RPM.Zingers and rev-up's are known to work well too as long as you can get it into that happy rpm range. I use Powermaster 5 or 10/22 fuel(used to use Taffinders 5 or 10 PA) and can do a pattern on 5-5 1/2 oz of fuel, pulling a 59-64 oz. stunter. I like adimisin type mufflers ,but others are known to work well too. I am constantly asked who worked over my engines an people can't believe it when I tell them that it is stock. Now my secret is out.

East Coast Flyer