Champion Spark Plugs-No Longer Champion

[CCowboy]

Had to abort a flight due to cyl 6 EGT going to zero on mag check.  Turned out to be not a fouled plug , but a defective Champion plug on the M20K, TSIO 360LB. 2 months ago all plugs checked OK at annual.  After engine rebuild 500 hrs ago, have had to replace 8/12 plugs.

 

Have read a lot of negative posts and press on the Champion plugs going bad with ultra high resistance.  This plug had over 12K ohms, the others 5K and below.  

 

This am changing all plugs to Tempest on next oil change in May. Strongly considering the Tempest fine wire.  Although 3X as much, they are said to last the TBO life of the engine. The other indirect financial consideration is the cost of scrubbing a mission due to one out of 12 bad plugs.  If the failure factor of massive electrode plugs are that much higher than fine wire, the dispatch reliability is probably worth the extra $600 over the next 1000 hrs.

 

Anyone with experience with this engine and fine wire plugs and/or Tempest v Champion, please chime in.

[carusoam]

Cowboy,

Have you seen this thread?

Connecting the two threads together.....

http://mooneyspace.com/topic/15074-201j-a3b6d-bad-champion-plugs-fry-magneto/#entry208814

There probably isn't a happy owner of a champion spark plug left on earth, regarding the high internal resistance situation.

Best regards,

-a-

[KSMooniac]

You won't regret the change.  Having said that, an engine monitor, some spare plugs and a couple tools in your fly-away kit can turn such an event into a minor delay instead of a complete mission scrub.  (although switching to Tempests will reduce the chances of needing to use those tools considerably!)

[Awful_Charlie]

A previous owner put Tempest fine wire in my Bravo 10 years and 1000hrs ago - they're still running fine. Avoided a trip to the grit blaster since I've owned it (5 years and 500 hours) but I did have to dig a spot of lead out of one of them a year or two back during annual, and had to re-gap one of them too (a bit of a fragile operation - quite possibly scraps the plug).

Maybe they know I've got a spare set in the cupboard!

[FBCK]

Put Tempest fine wire in my 231 two years back and they have been great.

[yvesg]

Cowboy, if you are lucky like I am, wait a bit... maybe you'll win some nice Tempest plugs in Oshkosh as part of the Mooney Caravan. The ones I won were installed last summer and run great!

Yves

[Hank]

There probably isn't a happy owner of a champion spark plug left on earth, regarding the high internal resistance situation.

Actually, the set of Champions I bought three? four? years ago from Byron is doing great. Lots of leaning, cleaning and gapping, very few lead balls. Don't recall exactly, but REM37BY seems right, may be 38BY.

Sorry, Anthony! Blame it on my carburetor. Many injected owners put fine wires in the bottom, others use them everywhere.

[NotarPilot]

Can you guys who run fine wires comment on any improved fuel efficiency with them?

[Nemesis]

Chuck,

 

When I bought N231NF I redid the mags and put in all new Champion massives. Less than 3 years later and 310 hours, I was having problems with the lower plug on #2 cylinder. Kerry McIntyre told me that was about the life limit of Champion plugs. I thought he had to be kidding but sure enough, 7 of 12 plugs had high resistance - greater than 5k ohms. The one that was in the bottom of #2 had 28k ohms. I have never really seen a problem with too many lead balls gathering or shorting so I went with Tempest massives.

 

Dave