|
Matronics Email Lists Web Forum Interface to the Matronics Email Lists
|
View previous topic :: View next topic |
Author |
Message |
kirk(at)mninter.net Guest
|
Posted: Tue Jan 10, 2006 8:12 pm Post subject: Rotax 912 |
|
|
Thanks to everyone that posted ideas for my Rotax 912 UL ignition problem.
As to the heart of the matter:
I have had a slight rough sound in the engine for about two years. I didn't not think much of it because I didn't have anything go wrong until last winter. The carbs started to leak fuel from the vent line. I sent the carbs to Lockwood, they checked out fine. I changed motor mounts, balanced the prop, and installed new carb mounts. I checked resistance with an ohmmeter on the ignition coils and found three were out of spec. I bought three new coils from Lockwood and changed all the plug wires. I changed all the sparkplugs as well. Still had the slight rough sound in both sides of the ignition, and the "B" side ignition had a slightly lower drop than the A.
I pneumatically synchronized the carbs three times getting Them exactly even. Still had the problem. I took off the gearbox and had Lockwood change out the springs. Slight roughness still there. I did that about two months ago.
About three weeks ago, I tried to fly the plane and the engine was more rough than usual. I did an ignition check at 3850 rpm. The B side dropped about 325 rpm.
I swapped the red leads from the stator, and the rough drop stayed with the B side. I swapped the four pole connectors from the modules to the stator and the rough drop stayed with the B side.
I asked Lockwood about the stator and they replied that it could not be the stator because that would be a total failure like the modules.
I called Lockwood again and they told me it had to be the spark plugs the plug boots or the connection to the coils. The plugs are only a year old with about 60 hours on them.
I checked all the boots with an ohmmeter and they were all in spec except one. The one was about 6.02K ohm. The book says 4.4 to 6 K ohm. So, this may be the cause I don't know yet.
As I stated before, I changed out three coils because they were out of spec. I thought maybe I should buy the fourth coil, but the rough drop in rpm is on the B side ignition, and the old coil is on the A side ignition. Keep in mind that there is a slight roughness in BOTH A and B side ignitions. It's just that the more rough, and 325 drop in rpm, is on the B side, and I cannot fly the plane.
Thanks again to everyone that posted a response. I will keep up the fight. The answers got to be there somewhere.
Kirk Martenson
Classic IV 912 UL
| - The Matronics Kitfox-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
Back to top |
|
|
morid(at)northland.lib.mi Guest
|
Posted: Wed Jan 11, 2006 4:17 am Post subject: Rotax 912 |
|
|
Kirk, did you try a complete new set of plugs?
Deke
| - The Matronics Kitfox-List Email Forum - | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kitfox-List |
|
|
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|