X3n0

I need help. bad. My limited understanding of how an engine is tuned and what I am experiencing first hand seem to be two different things.

Caliber 30 with OS 37 engine. futaba 9CHP super.

Throttle Curve is pt1. 15
pt2. 25
pt3. 50
pt4. 75
pt5. 100

Pitch Curve is pt1. 25 -3 Degrees
pt2. 50
pt3. 55 +6 Degrees
pt4. 65
pt5. 75 +9 Degrees

Engine needle(high ?) is out 1.5 turns. Low Needle is at factory settings.


I've tried everything that I know of and I cant get this thing to fly right.

Symptoms are : fires up fine. But if glow driver is removed it dies. So I increased throttle trim and it was ok.

then As I bring up the throttle stick there seems to be decent power till I get close to half stick then I get smoke and it bogs for a bit. Advancing past this point get me lift off and a hover for a few minutes before then engine completely cuts out and I plop back to ground (hover only 1-2 ft off ground for safety). I've left the radio settings alone and played with the engine needle alone, both leaning and enriching and I seem to ge the same result. I am at a loss. Glow plug is quite new.

Also at some points (I am sorry I cant rememeber what settings) my engine sounds like it has sort of bubbly sound. Not the "eeeeeeeeennnnhh" normal sound.

mtwister

You're too rich still. What fuel % are you running, and with what pipe? That engine typically runs very well. Also, if it was all brand new, did you tighten the carb screw when you took the motor out of the box? They're shipped loose. What you need to do is get the engine running decent, hold it in a hover for a minute or two and land, instatntly take a heat reading at the head. Let us know what that temp is. Also, I noticed on your PC and TC chart, that you have your TC going higher than the PC. You don't want this. Always have the two close to equal. You're over speeding in that set up. Also, glow plug brand plays a huge role in helis. Make sure it's an OS #8 or an O'Donnell.

X3n0

its a stock pipe. 30 % Nitro. the Plug is OS #8.

I didnt NOt know about the carb screw. Are those the TWO screws that hold the carb body to the engine ? Problem is I cant hover long enough. I do know that I can hold my finger on the engine for 4-5 seconds before it get uncomfortable . And how do I gt the TC close to the Pc. thank you for helping ..

Bugzilla

If you can hold your finger on it for that long, you are running way rich. If you don't have a temp guage, you can do the water drop test. After it runs for a few minutes and gets up to whatever temp it gets to, drip a drop of water on the head, if it takes 2 to 3 seconds to completely sizzle away, then you are running close to optimum temp. Any faster and your running lean, any slower, or if it doesn't sizzle at all, you are to rich. Ideally you are looking for the setting that doesn't bog when you punch the throttle, but still gives a nice plume of smoke through the whole throttle range. Hope this helps.

veralee

If the mechanics is set up "right" then from the curves it seems you're trying to hover at 50% throttle. I don't really know but that seems short. Try to borrow an optical tach and see what rpm you have at half stick. I'm guessing it's low. So you may need to increase the throttle at point #3... a wild guess maybe 70%. If you get it running more with the eeeeeee sound... then check temperature as others have said, and recheck the rpm.

Missileman

The best help you can get is hands on.
Check out the Whirlybirds. They where flying at Freedom Hill on 16 mile but I heard they can't fly there any more because of budget cuts to the parks. Wouldn't hurt to call them though.
I work in Pontiac and would be glad to help but I just don't know enough about engines in nitro helis, I can easily tune an airplane engine but that is quite different.
http://www.michiganwhirlybirds.com/