View Full Version : Loss of power when inverted on Raptor 50
Skarn
06-09-2008, 10:45 AM
Hey all,
First off, I haven't had time to check any of the obvious things like fuel clunk etc. But I wanted to get some ideas ahead of time before I go home and start troubleshooting.
Yesterday, I went out and flew a full tank of fuel without any issues....inverted hovering, flips, loops, no issues. I landed, refilled the tank, and this time, whenever I would do anything that wasn't perfectly flat flying, it would momentarily completely loose power until I righted it back level again. Even hard banked turns did this. I got lucky it didn't crash, but once level it would fly fine.
Any ideas for me to check? It's a OS 50 engine and I'm running 30% Cool Power Nitro. It was VERY humid and I was concerned about condensation in the fuel, but I've all but eliminated that since I figured I'd have problem all the time not just inverted.
Oh and I do run a header tank.
Skarn
BarracudaHockey
06-09-2008, 11:14 AM
Fuel lines would be my first guess.
gadawg58
06-09-2008, 11:17 AM
Does the problem start out right away even when both the header and main tanks are full or does it only occur once you've emptied part of the main tank? When the problem occurs is the header tank still full? I had a problem with the main tank clunk line with a small crack in the line that showed up after 1/3 tank was run out...noticed that the header tank would start emptying out while main tank was still 2/3 full...replaced the line and all is well!
Skarn
06-09-2008, 01:35 PM
Header tank stays full and the problem happens almost immediately when I start my first hard banked turn.
I'm guessing like the rest of you something to do with fuel lines or clunk.
Man, this reminds me of why my trex electric is sooo nice to just plug in and go! But there is just something so cool about nitro ;)
Skarn
alienteabagger
06-09-2008, 04:53 PM
Header tank stays full and the problem happens almost immediately when I start my first hard banked turn.
I'm guessing like the rest of you something to do with fuel lines or clunk.
Man, this reminds me of why my trex electric is sooo nice to just plug in and go! But there is just something so cool about nitro ;)
Skarn
It's the exhaust.... something in it, like crack. :smokin:
forjer
06-09-2008, 07:15 PM
Possibly as simple as a clunk stuck in an upper corner of the tank? Does it happen to run fine inverted?
Raven_darkcloud
06-09-2008, 08:57 PM
Look for build up in the lines or weak spots in it. I had this happen on a car before (real one)
Check for vibration wear on the tank due to rubbing of the supports or a small crack on the line connector. A very small hole would allow air excape faster than fuel, this could explain the diference in presure , thus engine behaviour , depending on the angle of the model.
and maybe the nitro leak goes unnoticed because your model ends up soaked in nitro anyway.
.......just maybe
Another posibility:
check that your flybar paddles are perfectly horizontal ( 0 pitch when blades are at 0 pitch)
if they have diferent pitch between them or they have ...lets say +5 it could fly perfectly fine and the paddles will even help to lift the heli, when you aren`t using any elev or ail or neg pitch. but as soon as you have any diferencial pitch ( due to swash angle) or neg pitch your paddles will star to generate excess drag ( in -4 neg pitch the paddles will work in the oposite direction +1), hence your loss of power.
Another.... check for excess play in your swash plate, seesaw and links,( by twisting the blades, both from max+ pitch to max - ) if you see twisting or any other movement that is not comming from the servo, this means you will set your pitch at home to (+11 /-11) and when you are flying it will behave (+11 /- something else)
This also modifies aileron or elevator behavior because the diferencial pitch is also affected
This might generate excess drag or/and too much pitch for your motor power.