Texan2

My Feedback: (4)

I have a ST 2300 on my TF T-34, fitted with a Bison Pits style muffler. The muffler was modified so that the nose gear could be mounted underneath and the exhaust pipes were moved so that they would extend into the scale exhaust pipes a short distance. The extensions were short pieces of aluminum tubes that were placed inside of the Bison muffler exhausts. The engine was fitted with a Perry Carb. The stock carb has never been used. The cowl opening opposite the engine head is blocked off. I'm using #8 glow plug with 10% Byron fuel. I'm using muffler pressure to the fuel tank.
Here is the problem:
Maiden flight ended in a dead stick landing. The engine died during flight after attempting to transition from 75% power to full power. Same results during subsequent bench runs with cowling on , and off. The engine idles great, has smooth transition from idle to full throttle, good midrange. Needle valve set to a slightly rich setting. It will run at full throttle in level position and at 45-50 degree incline (increasing rpm slightly) and back to level. If we reduce the throttle to 75% for a period of time and attempt to increase back to full throttle, the engine abruptly quits and smokes. I'm not alarmed by the smoking because the engine suddenly lost prop wash after being at temperature. Or, should I be?
What's up with this?

vasek

My Feedback: (4)

I would start by plugging one of the exhaust tubes to provide more back pressure. There is a discussion about this in the ST 2300 thread.

speedracerntrixie

My Feedback: (29)

The engine is getting too hot. I would back off on the nitro to 5% for starters. Not knowing what your install looks like as far as airflow through the cowl is concerned makes it difficult to offer any other suggestions. Prop wash does near nothing for coolin in a cowled installation. Cooling is a result of keeping air moving through the cowl while the airplane is moving forward. As a rule of thumb you want the exit opening to be at least twice the area as the air intake.

RCVFR

My Feedback: (7)

Ditto on plugging one of the exhaust tubes and lower nitro. I had one that behaved as yours does. The engine does not like nitro. The less, the better. I ran 5%, as it was more readily available than FAI. In testing with different nitro %, more was worse, up to 15%. I didn't waste the $ to buy more than 15%, as I wasn't using more than that in any other engines. The pitts style muffler does not allow enough pressure to the tank to allow for the delivery of sufficient fuel flow for sudden throttle increase. The smoking engine is telling you something!

It is a great engine when set up right. Enjoy!

vasek

My Feedback: (4)

Hi Carl,
did you resolve the issue ?

gerryndennis

Hi Texan,

What % oil are you running?

Is the 2300 one of the 'large' Super Tigres that don't run well on any more than 12% oil?

Dave H

1QwkSport2.5r

The 2000, and 2500 need 15% oil until broke in well broke in then 10-12% after provided its all castor oil. The 2300 needs no less than 18% oil.

Bax

My Feedback: (11)

Unfortunately, this is not quite true.

The G2300 requires that you use a fuel with no less than 18% oil content by volume. The S-2000 an S-2500 need a fuel with about 15% oil content until they are well broken-in. Then they can use a fuel with 10%-12% oil content as long as the oil is 100% castor oil. The castor oil content is mentioned because that's the oil used by SuperTigre when those engines were developed. Nitro content should be 0% to 5%. Higher nitro content could cause running difficulties.

1QwkSport2.5r

I stand corrected on which is which, I'll edit my previous post to reflect the proper information. Next question would be 'who would actually use all castor oil in anything?'. I know some do including myself, but how many hobby shops carry all castor based fuel? I have to make my own.

takEon

I run 20% oil in my 2300. I have used both straight castor and a blend. I do use low nitro. Maybe my engine forgot to read the directions but it runs fantastic! People always ask about my 2300 after a flight. It did take awhile for break-in, but offers fantastic power and reliability in the 15 years I have been flying mine.