Champion Massive plugs

[TomD]

I had a cylinder that would not light up at low rpms. Traced everything we could think of to find the problem. Swapped #3 and #5 plugs and problem seemed to go away, but I was still a bit spooked.

My IA mentioned that he has a box full of Champion massive electrode plugs with failed internal resistors. Seems as if they would spark on the tester but the spark is weak.

I swapped to Auburn aka Autolite finewires just to be sure.

Don't know if this is wide spread but thought I would throw it out there.

TD

[Maule 9V]

I use the Autolite Fine Wire plugs in the lower positions (Cyl. 1 & 2) where ground fouling can be a problem. It was a good move.

[donknee]

I had a problem last year and then again this year with the Champion RHM 40E's. It happens within two hours of flight after the annual (spark plugs are cleaned at annual). Indication is a bad "run-up" on one side. Could be mag, mag wire, spark plug...right off the top. Easiest one to eliminate for me is the spark plug (maybe the most likely, too).

What worked for me this year, was to let the engine cool, start up again with the cowl off. Run for about 5 minutes at an idle or 1000, until I just started to see the EGT start to register, I have the mix-miser. Shut down, with an infrared thermo gun, measure the temperature of each spark plug. I had 165-175 on all the plugs but one...it was 135. I pulled that plug it was wet with fuel from not firing. Put in a new plug, and problem solved.

Last year we kinda felt the plugs and pulled a few of them and found the wet one. This year I asked Jeremy and he said infrared thermo gun or melt stick.

I may be off on this assumption, but I think maybe the plug got dropped and damaged when being cleaned at annual. Either that or they don't make them like they used to. I had the cowl off diagnosed, repaired and cowl back on within an hour...so, I hope this can help someone else out, too.

[UP-M5]

i used to consistently have bad run ups.... switched to fine wire autolites in the bottom and now it is good. will be switching to all finewires shortly.

[donknee]

Somebody (maybe TomD) said the Autolite's were about 1/2" shorter , too, which gives you a little more clearance with the cowl. This plug was #2, upper. I've been told the fine wires are more resistent to fouling from lead and oil.