flyrotary@lancaironline.net Mailing List Archive

Jeff, I have gotten RF interference from resistor type spark plugs including BR10EIX when the internal resistor element fails and an arc occurs internally. This can be verified by checking the resistance between the center electrode tip and the end where the spark plug wire attaches. The resistance should be in the neighborhood of 5000 ohms with a good plug and infinite or open circuit on one that has failed. My experience is that this type of failure is unrelated to SAG. Steve Boese > On Aug 30, 2020, at 4:34 PM, Jeff Whaley jwhaley@datacast.com <flyrotary@lancaironline.net> wrote: > > ◆ This message was sent from a non-UWYO address. Please exercise caution when clicking links or opening attachments from external sources. > > > I have an unusual experience to recount about electrical interference. I parked my Mazda-Powered 2+2 for about 2 weeks in favour of flying the Tri-Pacer for a while. It was parked during a hot/dry spell and I picked it up after the humidity increased, on a misty rainy evening after work. On the ground and at low RPMs everything seemed normal but once I was airborne at full throttle and even at cruise RPM the radio was 100% static - like the squelch was adjusted wrong - I endured this for a 20 minute flight. > Today it was relatively dry so I decided to fly it and see if the symptom persisted ... it was slightly better but still a lot of static. > I put in a new set of irridium spark plugs BR10EIX, took it up for another flight and it was now crystal-clear - not even one chirp. > I have never experienced SAG - Sudden Attention Getter - which has been attributed to failing spark plugs ... so I am wondering if anyone who did experience SAG, if they ever had increased radio static prior to their plugs really failing? > These plugs are about 2 years old and have about 50 hrs on them ... I don't see anything obviously wrong with them, they look like any plugs I've pulled over the years. My educated guess (35 yrs RF experience) is that what carbon build-up on them is causing some of spark to be transferred to the engine block ground ... > Any other suggestions ?? > Jeff > <SparkPlug-4.jpg> > <SparkPlug-1.jpg> > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html