puzzling problem help please.

[choppaholic]

here the problem?

engine starts to over rev,
Throttle hold
Engine still going like nuts.
Have full control on heli,
Autoed down,

Engines still revving full throttle.

No drive to the blades so I plug the exhaust and kill the engine.

What just happen???

What I did before.

New heli, built run in, throttle set correctly.

6th tank leaned out went up.

Though lets get the governor on, switched it on mid flight everything seemed fine then idle up. Went for a tic toc. Engine went dead quite and then kicks back to life full throttle.

Throttle curve normal is 0 17.5 40 65 100.
Idle up 100 55 40 55 100.

What am I doing wrong..

The thing that’s puzzle me is why would it rev with throttle hold, hold works fine.

Cant be loss of signal as I had full heli control

Governer is working and sensing magnet properly
But how can it rev on hold …

[tonystevens]

Has this been happening scince you started using your gov?if so i would start looking there

EDIT: Check that your rotor arm hasnt come loose on the carb too.

[choppaholic]

yes, just check the governor on other heli it works fine, but what i cant figure out is why would it keep going even at throttle hold??

[Jamin_00]

Throttle servo wire? Check that and make sure it's connected properly to the rx.

Might sound silly but I had it come lose in a rx before.

[choppaholic]

just checked everything, all looks normal, when i switched of the engine the throttle was working fine, but cant recall if it was stuck at a position, when i go back to the pits it was not stuck at 100 it was in the idle position and the throttle lever is not slipping either the mark on throttle was also at idle, going now to test again, may be the carb is gone>>

[choppaholic]

just checked everything, the only thing i can see is the idle settings have all changed it was at like 1/4 throttle at low stick. but before the flight i had just reset the throttle re-tightened everything. so i am puzzled why the position changed after this event.

the no drive is because of a slipping on way bearing on the main gear. good that happen on the right time or else i would have to wait for fuel run out.

but why wouldnt the throttle hold work it was working fine before and now. ????

[electricsceadu]

check that the throttle hold is set up to turn the gov off

i've seen it with a gv1
hold works ok until the gov was turned on
the pitch range was working as in hold but the motor was still at the gov rpm

[choppaholic]

not sure how i can do that on the DX7 mate, but when i just run it on the bench the hold and throttle are working correctly. i am not sure whats happening, just stripped the engine everything seems fine

[Britflyer]

What engine? Is it getting hot? If it overheats the carb could be sticking, so even though the servo trys to move it can't.


Paul

[choppaholic]

i only checked the back plate that was not even hot, but when it rev hard yes it was hot, but this happened in about 1 minute into flight so i don't think it heated up before this happened.

[pchristy]

....... but when i just run it on the bench the hold and throttle are working correctly.(

But when you try it on the bench, is the engine running? If not the governor won't be getting any signals from the sensor, and will revert to "normal".

First thing to do is fly it *without* the governor in circuit, and see if you still get the same issue. That should tell you where the issue lies......

[choppaholic]

yes engine running, and the governor seems to be doing its bit when i try and stall the head buy hand (no blades on of course). off to the field not to see what up with it.

thanks guys

[GravityKills]

>>Engines still revving full throttle.

>>No drive to the blades so I plug the exhaust and kill the engine.

Possibly your clutch is burnt and / or broken.

[Mslater]

Govenor in wrong RX Channel ?

If its the align gov, you need Ch3 and Ch7 (on futaba) I don't know about other radios but you will need 2 channels to control it properly

[Mslater]

Er just thought of something that happened to me.

Engine running backwards due to a back fire.

I think you are suffering something like this - maybe because the govenor is getting the wrong signals - but i'll bet it is and is causing a backfire and reversed engine.

Results in high RPM with no drive.