question about engine running...
 

Hello guys, I am in fact not a beginner but I have a beginner question I guess:

What is the maximum length of time we should fly a plane at maximum speed? thinking about the engine during a flight of 10mins for example.

For instance, I have a mustang PTS flying with an OS 46FX, the power is very nice of that engine and I like to fly it at max throttle (even though sometimes I keep it at 95% throttle). The thing is that I feel I am somehow "abusing" of the engine if I fly too long at full throttle..... is there any concern that I burn out the engine or the piston gets overused or damaged if I fly too long the plane at max throttle????? I do not want to damage my engine, therefore I usually fly at mid-stick but I would prefer to fly longer at max throttle...

Thanks!

RE: question about engine running...
 

As long as the needle valve is set correctly and the engine does not go lean, I do not see any problems with running it at full power. Good Luck, Dave

RE: question about engine running...
 

Same here, about 3 to 500 RPM off max and it should be fat enough.

RE: question about engine running...
 

Back in the 60's we flew wide open throttle all the time

RE: question about engine running...
 

Back in the 60 you were doing it in a tweed sport coat and a pipe in your mouth!!:D

RE: question about engine running...
 

RE: question about engine running...
 

Uh, I'm going to change clothes now.:D

RE: question about engine running...
 

Go and talk to a pylon racer about running wide open for a whole tank....sure it only lasts for a minute and a half at 25,000 rpm but who's counting....

RE: question about engine running...
 

Pedel to the Metel Baby!!!:D

RE: question about engine running...
 

Hello guys, in this case, I just tun the engine on the ground at max throttle but I just tun it with my 'ears'.....

How can I be more precise and make sure it does not go lean on the air after 5mins full throttle????

I have both: temp gauge and tachometer..... can I use them for that???? how???

Thanks



P.S. I have those tools but I usually use them in my nitro helis, never in planes cause so far it is enough with my 'ears' but If I want to fly at full throttle all time, I would like to be double sure that I properly tunned my engine...

RE: question about engine running...
 

To use the tachometer to tune your engine, you put the tach on the prop while leaning out the needle until it peaks. Read that peak rpm off of the tach. Then re-tune the needle until the rpm is about 500 rpm below that peak value. Then you are good to go flying.

RE: question about engine running...
 

We have some guys in our club that have a toggle switch for a throttle. All the way off or all the way on!!! They seem to fly several times a day and as many times a week as they can.

CGr.

RE: question about engine running...
 

Hello, sorry, some clarifications:
1. what do u mean by "peak"
2. what is "line out", close the main needle or open it some clicks???? Before this term, I just knew "lean in" (close the needle) and "rich out" (open the needle)...

Thanks!

RE: question about engine running...
 

By peak I mean until you see a maximum rpm. What will happen as you are leaning the needle is the engine rpm will pick up until a maximum is reached. Then if you keep going, you will get too lean and the rpms will drop fairly quickly. This maximum rpm is referred to as the peak. So get a reading on what the peak rpm is of your engine setup and then richen it up a little until the rpm is about 500 below the peak rpm.

RE: question about engine running...
 

Matador,

"Lean Out" and "Lean In" mean the same thing, like "Flammable" and "Inflammable". Just delete the "out" or "in", and lean the mixture by screwing in the high speed needle.

Actually, with some engines, I can richen the air-fuel mixture untill RPM starts to drop off. Then I lean the mixture until I just get back to peak RPM, and call it good.

Best wishes,
Dave Olson

RE: question about engine running...
 

"Peak" Highest point

RE: question about engine running...
 

Ok, ok,
got it, I'll do that....
put the tachometer, max peak by leaning, when reached, then rich up to reduce about 500RPM and then is good to go!

Thanks a lot!!!!!

I'll fly full throttle then!!! the mustang pts flies very nice in high speed.