EGT probe question

[planeolbob]

Hi everyone,
Well, its always something.

After one of my mags stopped while flying in Nov. (I turned on my electronic system and flew back to OJC but not before checking if you could fly with only two cylinders - 84 mph on a cool day with a light load!). So I bought and installed two new mags. pulled the heads and inspected them, installed new plug for the mag side and new plug wires for the electronic side. Fired the engine up and it ran better than ever.

However, my EGT read out went wacky on my as shown in the video at this link

https://www.flickr.com/photos/planeolbo ... /lightbox/

I believe that the probes were damaged when removing or reinstalling them as they had some build up after 400 hours.

What do all of you "Grey Beards" think.

Bob (to hot to fly) Mika

[mike.smith]

Seemed like the EFIS was what was going wacky, since it kept turning off. What was up with that? Since more than one EGT number seemed to be off the charts then I don't think it's the probes. Seems like a grounding issue, or some other electrical gremlin. Maybe I'm not correctly interpreting what I'm seeing?

[planeolbob]

I was turning the unit on and off to try to reset it

[WesRagle]

Hi Bob,

A shot in the dark. Are your pipes wrapped? If so, and if the unit requires the TCs to be grounded, maybe one of them didn't make it through the wrap (and it's driving the TC amp out of it's common mode range).

Wes