1500 rpm

Yes ran up the engine today. Was very windy today so decided to face it out of the wind, with the chocks and 2 pegs into the ground holding down the fuselage.
Getting good at starting this engine, always goes, after a few tries so that’s good 🙂

Now back to the Tacho:

The tacho works now so very happy about it, still want to check it against a external speed sensor, something optical, but yes pleased. The not so good thing is that it possibly doesn’t go as fast as was hoping. It was doing 1500 rpm which according to the manual of the engine equates to about 45 hp. Maximum speed is suppose to be 2000 rpm. I am sure, and always thought that the engine is limited by something. It doesn’t produce any more power from 40% throttle too 100%. Maybe its the carburetor… So soon I will need to start getting some experts in I think, to see what they think.

I also know that, when on the ground, the prop won’t go at the full speed, it will go faster when flying, but I somehow don’t think that’s 1/4 extra….. To be continued.

But happy with the tacho working 🙂

A few hours later:
Still thinking about that carburetor….
The engine runs OK at low rev’s, but at higher rev’s is limited by something. Also the mixture control is not behaving, basically closed mixture, it should slow the engine down, or at least do something, so that’s wrong.

But I have had problems with the priming valve in the past. What if it’s not leaking anymore at low rev’s, but at higher rev’s were the engine is trying to suck more air, its possible that some fuel is starting to come through this priming valve. When I open the priming valve just a little bit while its running, the engine dies straight away, so just a little bit of extra fuel will surly stop it from going to max rev’s. I know that my carburetor is an earlier model and that later models had the priming valve modified because of these or similar issues……

THAT’S my thought at the moment…..

Maybe I should go to a new simple carb that doesn’t have these issues.

Leave a comment