Spark Plug electrical noise
in 912 / 914 Technical Questions
11 years ago
After I was visited by Rick Wright of Copperstate Aero who solved my 914 engine problem I tested my radios found a high level of noise coming from the engine. S/N I estimated 1:1. Makes it hard to hear the tower and other planes.
I have checked all the grounds from my engine through the grounding of my instrument panel. I installed .01MF caps on the ignition switch, checked and replace 4 bnc connectors. Shunted the panel ground directly to the battery. After all that done I really havent impacted the electricle noise. The wires from the CDI modules to the ignition are shielded and well grounded. The engine is well grounded. I have outside star washers under all the bolts that provied grounding to the engine. I'm able to squelch the noise off but it's annoying to have the noise riding on top of any and all transnmissions when the squelch breaks. Oh I have a composite (Plastic) plane
I have used a handheld radio with a peice of wire stuck into the antenna and can hear the noise being transmitted. Abount 60 hours previously I replaced all my ignition wires with Rotax supplied wire. The plugs were purchased from Rotax about 70 hours agokand were just regapped to .028. A few of the plug caps were replaced because the connectors opened up. Performing a run up there is no difference in noise when running the engine from the Left CDI or the Right CDI.
I know there are a few things I've forgotten to add to the mix but that's all I can say now. I was told that trouble shooting electrical noise in a "Plastic" airplane is 5% knowledge and 95% Voodoo. Short of planting a potato in a full moon and dancing around in a circle I've run out of ideas.
Appreciate advise and information you can provide. :side: :silly:
I have checked all the grounds from my engine through the grounding of my instrument panel. I installed .01MF caps on the ignition switch, checked and replace 4 bnc connectors. Shunted the panel ground directly to the battery. After all that done I really havent impacted the electricle noise. The wires from the CDI modules to the ignition are shielded and well grounded. The engine is well grounded. I have outside star washers under all the bolts that provied grounding to the engine. I'm able to squelch the noise off but it's annoying to have the noise riding on top of any and all transnmissions when the squelch breaks. Oh I have a composite (Plastic) plane
I have used a handheld radio with a peice of wire stuck into the antenna and can hear the noise being transmitted. Abount 60 hours previously I replaced all my ignition wires with Rotax supplied wire. The plugs were purchased from Rotax about 70 hours agokand were just regapped to .028. A few of the plug caps were replaced because the connectors opened up. Performing a run up there is no difference in noise when running the engine from the Left CDI or the Right CDI.
I know there are a few things I've forgotten to add to the mix but that's all I can say now. I was told that trouble shooting electrical noise in a "Plastic" airplane is 5% knowledge and 95% Voodoo. Short of planting a potato in a full moon and dancing around in a circle I've run out of ideas.
Appreciate advise and information you can provide. :side: :silly:
