St3000
 

hi,i have a few questions,i have a 3000 on an ace big bingo,it seems to be having a problem turning up. it only turns a topflite power point 18x8 7500 rpm,and i am not sure if the needles are set right,but it transitions great,and seems to hold it's rpm ok. but, the engine sat for a while,and i was afraid the carb was gummy,so,i had another nib 3000,and when i got the carb off of it,it had a sleeve around it,took the sleeve off,and it fits the first one,but rpm doesn't seem to be any better. it does still put out some nasty black oil on the plane as if to not be broken in fully. by the way.i am running byrons ST fuel,and for some goofy reason,it likes an idlebar plug,any help???????

St3000
 

It doesn't sound like the engine's running badly at all. The top RPM sounds good, and if the idle and transition are good, then it's running well.

As far as the exhaust stream is concerned, you should capture some of the oil on a piece of white card stock. Just hold the card near the muffler outlet and let a puddle of oil accumulate. Take the card away, and let the oil absorb into the card. If there are any metal particles in the exhaust stream, you'll see them on the card. If there are no particles, then the oil is most likely 'cooking' inside the muffler. That can turn a synthetic oil dark. Also, if the engine's running a bit hot, that can also cook the oil.

You may wish to try a fuel with a bit more oil content to see how it performes. The big 'Tigres need a fuel with about 15% oil content until the first few gallons' worth of fuel's been run through them. Then you can go to a low-oil fuel if it's mostly castor oil (that's per SuperTigre).

ST 3000 running problem
 

Hi, I'm not sure if you know or not, but according to Supertigre, The ST 3000 Is the most efficient at an RPM range of 7300-7800 rpm. I don't understand why everyone is so concerened about reaching RPM's above that. If you are giving yourself a headache trying to get over 7800, you're wasting your time. I just thought i'd let you know. If you're that concerned about reaching the most RPM that you can get, try different brand props. Again, I think you're wasting your time.

I have a ST3000 swinging a 18-10 dynathrust prop at 7700. That's perfect and i'm running it on a 17lb 1/4 scale Aeronca Champ with a 9 ft wingspan and it's got TONS of authority !!

Happy flying !!

St3000
 

Markus is correct. We usually run the engine in the mid-7,000's or so. As I said above, if you have that top RPM, a good idle, and a good transition, you're running the engine correctly.