One thought, where is your T- for the vacuum to the two MAP sensors, suggest having separate lines for full isolation, if rub through-leak accured then would not affect both.. wife says have to leave now ,.David
From: "steve Izett" <
flyrotary@lancaironline.net>
To: "Rotary motors in aircraft" <
flyrotary@lancaironline.net>
Sent: Friday, August 5, 2016 7:31:14 PM
Subject: [FlyRotary] Finding the gremlin
Hi Guys
We got some further fault finding done today towards isolating the cause of the massive missing problem with our Renesis 4 port.
The troubling symptom / major problem is as we approach 23-24” MAP at various prop pitch and rpm’s (both A and B computers),
with very little warning begins to miss and then pretty much go immediately into massive missing and popping in the exhaust.
Just before the bad stuff begins the EGT’s read 1540 and 1440.
I have only done mode #3 programming and adjust the mixture with the manual mixture control while watching the narrowband. The mixture tables were reset.
It stages at 19”Hg as per Tracy’s recommendation for Red and Blue Injectors.
Also the Skyview and EM3 stops displaying RPM at around 6000 rpm. The EM3 reads NOP instead.
So order of events today:
I wondered previously what the seals where like so having received a new $22 pressure transducer I took out trailing plugs and
grabbed some pressure data while cranking.
See plots in WORD file attached - (File to big, I’ll have to reduce before posting)
All faces around 80psi when cold. Rotor #2 has one pulse down by max of 6 psi compared to the highest pulse. Does this mean that side seal is leaking?
We then went after 3 key possible problems:
1st being Engine monitors holding Injector #1 open so:-
A. Disconnected Dynon engine monitor to isolate it as a cause of disturbing Injector #1. No change.
B. Disconnected EM3 to isolate the same as above. No Change.
2nd being Pulses in the intake manifold messing with EC2 fueling.
We inserted a 0.6mm restriction in MAP sense line. (This line then ’t’s’ of too A and B Computer MAP’s. No Change.
3rd Renesis CAS generating higher input voltage. Tracy recommends 1K across CAS’s.
I think this mod may have been done. See photo of EC2 PCB below pin 4 & 23 both tied back to pin 22 via something inside the heat shrink.
Note to Tracy. - Did you incorporate in your code any way of knowing if the EC2 entered a watchdog routine?
So I’m stumped for the moment.
At least we know more of what the problem isn’t, Which is helpful.
Appreciated any input.
Cheers
Steve Izett
<EC2PCB.jpg>