Another low-percentage (1 confirmed) but possible cause is the controller coming loose in the PLCC socket. Pop lid off of EC2 (careful not to touch pins) and press gently but firmly in center of chips – they should NOT move; i.e., fully seated to bottom of socket. Jeff From: Tracy <rwstracy@gmail.com> Subject: Re: [FlyRotary] Fuel map scrambled. Date: Thu, 22 Aug 2013 06:48:11 -0400 To: Rotary motors in aircraft <flyrotary@lancaironline.net> I've written about this so many times I've lost count. The scrambled map table problem is ALWAYS caused by electrical noise spikes. The root cause of those is poor electrical system layout including ground distribution. You can sometimes fix the problem by addressing the individual sources (coil power inputs, starter solenoid, etc) but its also important to have a proper architecture to begin with. I have a two page guideline for this in the installation guide for last several years but it's too many bytes to post here. Email me a request and I'll send it direct if you want a copy and its not in your installation guide already. Tracy Crook Sent from my iPad On Aug 21, 2013, at 22:09, hoursaway1@comcast.net wrote: 1st..... am now on the ground safe & sound, no damage normal landing. The story goes....... Level at 2500' above Mason Jewett Field, ( hazy evening, aprox. 7:30 pm ) on the down wind abeam of the end of the runway, 4600 rpm, ? MAP, 125 MPH ind., 3rd circle around the patch getting ready to put in full cruise pitch on prop to do a full throttle numbers gathering. Then the eng. started running very poorly, missing, stumbling hard, destict loss of power, tryed to descend & come around to land but am high & hot with ( RV's need air brakes ) eng. smoothed out, chose a sweet spot & climbed out to go around,,, low but climbing, ran smooth 4000 rpm, landed ok. Before shutdown, checked fuel map bars for EC2 on EM2, some in the middle some at the bottom,,,Lean,,, why did the fuel map scramble suddenly, steady cruise flight, made no changes at that time? At the airport by 6:30, pull plane from hanger to do two tests tonight, 1st. run eng. at low power/idle like sitting in line for takeoff from Osh or ?, how long can we stay running without getting to hot, 18 min. coolant 205 F, oil 175 F, ok that's good enough for me lets go fly & do the prop full cruise pitch test run. That was the start of the evening, ended differently than I would have liked. But nothing bent. Did not reset EC2 yet, am going to start eng. & check to see if computer B runs ok, did not get a chance to throw that switch, when I found the sweet spot I changed nothing, just came around & landed. What is the fix for this anomaly?? David R Cook RV6A Rotary This message, and the documents attached hereto, is intended only for the addressee and may contain privileged or confidential information. Any unauthorized disclosure is strictly prohibited. If you have received this message in error, please notify us immediately so that we may correct our internal records. Please then delete the original message. Thank you.
Another low-percentage (1 confirmed) but possible cause is the controller coming loose in the PLCC socket.
Pop lid off of EC2 (careful not to touch pins) and press gently but firmly in center of chips – they should NOT move; i.e., fully seated to bottom of socket.
Jeff
From:
Tracy <rwstracy@gmail.com>
Subject:
Re: [FlyRotary] Fuel map scrambled.
Date:
Thu, 22 Aug 2013 06:48:11 -0400
To:
Rotary motors in aircraft <flyrotary@lancaironline.net>
I've written about this so many times I've lost count. The scrambled map table problem is ALWAYS caused by electrical noise spikes. The root cause of those is poor electrical system layout including ground distribution. You can sometimes fix the problem by addressing the individual sources (coil power inputs, starter solenoid, etc) but its also important to have a proper architecture to begin with.
I have a two page guideline for this in the installation guide for last several years but it's too many bytes to post here. Email me a request and I'll send it direct if you want a copy and its not in your installation guide already.
Tracy Crook
Sent from my iPad
On Aug 21, 2013, at 22:09, hoursaway1@comcast.net wrote:
1st..... am now on the ground safe & sound, no damage normal landing. The story goes....... Level at 2500' above Mason Jewett Field, ( hazy evening, aprox. 7:30 pm ) on the down wind abeam of the end of the runway, 4600 rpm, ? MAP, 125 MPH ind., 3rd circle around the patch getting ready to put in full cruise pitch on prop to do a full throttle numbers gathering. Then the eng. started running very poorly, missing, stumbling hard, destict loss of power, tryed to descend & come around to land but am high & hot with ( RV's need air brakes ) eng. smoothed out, chose a sweet spot & climbed out to go around,,, low but climbing, ran smooth 4000 rpm, landed ok. Before shutdown, checked fuel map bars for EC2 on EM2, some in the middle some at the bottom,,,Lean,,, why did the fuel map scramble suddenly, steady cruise flight, made no changes at that time? At the airport by 6:30, pull plane from hanger to do two tests tonight, 1st. run eng. at low power/idle like sitting in line for takeoff from Osh or ?, how long can we stay running without getting to hot, 18 min. coolant 205 F, oil 175 F, ok that's good enough for me lets go fly & do the prop full cruise pitch test run. That was the start of the evening, ended differently than I would have liked. But nothing bent. Did not reset EC2 yet, am going to start eng. & check to see if computer B runs ok, did not get a chance to throw that switch, when I found the sweet spot I changed nothing, just came around & landed. What is the fix for this anomaly?? David R Cook RV6A Rotary