ORIGINAL: jsf125
Hi,
I was wondering if you could give me some advice and help with my JJ1400 engine. I just got the rotor assembly back from being dynamically balanced at RTI, and I made all modifications described in post number 608 of this thread. I also sealed up the front case seam and rear tail cone seam with a high temp copper silicon. When it was run without being sealed up, there were excessive blue flames coming out the back, and a jet of air coming from the front seam of the outer case. It was too much to ignore.
So, I just got done running it with it being all sealed up, and at the lower rpm's the engine experiences a rpm drop of about 1,000 rpm just about every 4 - 5 seconds. I am sure that it is not the fuel pump because pump power is constant and doesn't fluctuate with the rpm drop. Temps are very good at about 520 C at idle. I am just trying to figure out what is causing the rpm drop. It doesn't experience the drop at high throttle positions. When I say higher, I mean from about 20% all the way up to 100% power. Do you know what might be the problem??? Maybe I should just ignore it and go flying?! It would make me feel a lot better if I knew what was causing the rpm drop.
Thanks for you time,
Brandon
Brandon
The tips in 608 were given to Airbuspilot2 in earlier PMs with Fernando as he will confirm. His earlier problems was rear bearing failure in part. So either removing the O ring or cutting it flush was a part answer as the machining tolerances vary. If getting rear bearing failure the lubrication delivery amounts/flow was another problem that required to up the flow by 200-300%. Since the early restrictor barely gave enough.
The drop in of 1K is the fuzzy logic adjusting say at idle when set 46k it hunts beween 45-47k trying to settle and is a feature of the stablity delay. Nothing to wory about if it goes up to 160K as over a few runs it will settle down. Unless you want to tweek FADEC setings for aerobatics (then PM over). The other major problem was the Non iconel CC breaking up at happened for Fernado loosing performance but Joe replaced it.
I'm just curious what FADEC settings Airbuspilot2 decided to use from those PM'd over to try out. The vid and performance was spot on.
Paul
RCdriver