Im new to this site, but ive heard so much about it and ive actually gotten quite a bit of info from it from searches on the web.
Ive got some questions and or concerns regarding the tuning of the Zenoah 26.
First a little background on myself:
Ive recently started an aerial photography company in Denver Colorado. I am using the Bergen Intrepid EB equipped with a standard muffler and the AP-2000i (which I haven't tested yet), but finally got set up (Thanks Mark!). My radio is the Futaba T7CHP.
I have already perfomed some test hovers and basic maneauvers with it and it hovers like a dream. My questions are as follows:
I am having serios vibration issues with the machine. Among many minor hardware issues is a serious issue, which if I don't fix fast, could cause some serious issues down the road. I recently had the two bolts that hold the tail rotor gearbox to the boom shear off. Luckily, I noticed the tail rotor putting off some minor diaganol motion from time to time when in a hover and landed it quickly. Of course the bolts where held in with loctite, so the removal of the remaining bolt portions from the blind holes on the gearbox was a little tricky.
I am contributing this to what I think is a engine problem. I have read a post on here stating to monitor the landing gear when in a hover for clarity. If the gear appears blurry, then there is too much vibration. Well I performed this test today and the gear was clear as can be in a hover, but the T/R gearbox was pretty blurry. Which indicated to me there is severe vibration in the aft of the machine. I have also read in a forum from Chris Bergen, stating to remove the idle screw from the carb, which I have not done yet. Is this recommended?
Additionally, during the throttle up procedure, when at about half stick (just prior to lift off) the engine boggs down pretty dramatically. If I give it another stick positoin of positive power it recovers and regains rpms. If left at that position, the engine will die. Now, during idle through half stick, the engine is perfect, and during a hover the engine is perfect. Perhaps my thottle vs. Pitch curves are off.
My curves used in idle 1 are as follows:
Throttle curves and points: 1-0% 2-45% 3-90% 4-92.5% 5-95&
Pitch curves and points: 1-30% 2-40% 3-50% 4-75% 5-100%
My blade pitch at full negative is about 3 degrees and full positive is about 9 degrees.
Are these sufficient curves for this machine?
Any help with these issues would be greatly appreciated!
Thanks in advance everyone