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Spark plugs

That OHMS test works!
New Tempest plugs smoothed things out..!
In Contientals and Lycomings.
 
Yep! Run Tempest, any Tempest. I have been running Tempest since I learned about this issue.

My next door neighbor tested his 200 hour Champion plugs he was running in his O-320 powered Citabria after I informed of this issue, all 8 failed by a wide margin.

Tempest as a neat little very quick and easy to use device you can buy from Spruce that tests resistance, its a simple go/no go tester, about a hundred bucks, worth it in my opinion.

Kurt
 
Are they worth three times as much? How long do they last? Is there a performance difference?

Yes I think they are they are worth it.

If you dont want to spend that much then buy the standard Tempest plugs, either way, get the champions out of your airplane and get Tempest, at least until Champion fixes this issue.
 
Are they worth three times as much? How long do they last? Is there a performance difference?
Don't think there's much of a performance difference, but the fine wires are FAR more resistant to lead fouling, and should last easily 3X as long as the massive electrode plugs. There was a recent discussion of this on another forum, and a couple of flight school operators reported that is was fairly routine to go full TBO (Lycoming engines) on a single set of Tempest fine-wire plugs. Mind you, they also teach "aggressive leaning" on the ground, and teach their students to operate LOP in cruise flight. But I was pretty impressed.
 
I have Tempest massives now.


Yes I think they are they are worth it.

If you dont want to spend that much then buy the standard Tempest plugs, either way, get the champions out of your airplane and get Tempest, at least until Champion fixes this issue.
 
Are they worth three times as much? How long do they last? Is there a performance difference?
I put them in the 180 with new cylinders 950 hours ago and they show no wear, far smoother in my opinion and absolutely no radio interference. Recently changed from Tempest massive in the cub when those started to football at 800 hours.

Spendy but sometimes you can catch a show deal.
 
Fine wires last three times as long but cost three times as much. If there is no performance gain then I see two advantages. 1. Less likely to foul 2. Easier to inspect and easier to clean at annual.

Disadvantage- shelling out $1000


Don't think there's much of a performance difference, but the fine wires are FAR more resistant to lead fouling, and should last easily 3X as long as the massive electrode plugs. There was a recent discussion of this on another forum, and a couple of flight school operators reported that is was fairly routine to go full TBO (Lycoming engines) on a single set of Tempest fine-wire plugs. Mind you, they also teach "aggressive leaning" on the ground, and teach their students to operate LOP in cruise flight. But I was pretty impressed.
 
Fine wires last three times as long but cost three times as much. If there is no performance gain then I see two advantages. 1. Less likely to foul 2. Easier to inspect and easier to clean at annual.

Disadvantage- shelling out $1000

One Aviation monetary unit...

Easier to do a one time 1,000 than have to keep pulling and replacing plugs. Had a clinker ground out a plug in a nasty spot once, thought the engine was going to come off the mount. I like less worry in my engine.
 
Long story short.... had never done the resistance check before this.

Friend with 185 had a couple trips left to do to cabin. Asked me to look at engine since it had gotten rougher over the end of the summer. Planning new engine over the winter.

I looked at fuel nozzle flow equality, all the fuel system screens, verified proper fuel flow, checked magneto timing, checked compressions, looked for induction leaks, air filter and plenum, and checked muffler for obstructions.

Nothing amiss

Owner had cleaned plugs in attempt to fix roughness.

But I cleaned and sparked them anyway. Did resistance check and all but 2 were in the 15000 to 25000 Ohm range

I didnt have new plugs so I found enuff plugs from the junk spark plug box in the proper heat range that made less than 5000 Ohms on "this new Ohms test deal".

Owner called after first flight and said that engine had never run smoother.

Been doing resistance check on all recips since then and will continue to.
 
This is a surprising amount of discussion over a 4 year old article and an issue that has been known for close to 10 years. Champion claims they have fixed their production issues. Who knows? Maybe. I have found a couple of Champion plugs that failed in the decade, but haven't seen failures to the level I would consider to be a pervasive problem.

Personally, I run massive electrode Tempest in one plane, and NGK autoplugs with Emags in the other. I don't buy Champion simply because they cost more, and as discussed, have a reputation issue.

-Cub Builder
 
This is a surprising amount of discussion over a 4 year old article and an issue that has been known for close to 10 years. Cub Builder

and the AD or SB issued number was???

or was it just internet theory ???? I don't follow/pay attention to much internet theory...

not saying i don't appreciate the heads up... it makes sense!!
 
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Better late than never!!

I live in a cave, in the dark, and can not read unless the magazine has pretty pictures. One of the reasons I keep membership is to get the great calendar to look at.:pty:

This might be well known to some, but was the first I had heard about all of this. Maybe I should try to exit the cave once in a while.:oops:
 
I tested my Champion plugs when I overhauled my engine last summer, and all but one measured open with an ohm meter that would read in the mega-ohm realm. I took one plug apart, and could see where the internal resistor was arcing to its contact. Replaced with Tempest massive. The engine was running smoothly, but there was some tracking in the mags - maybe due to the plugs?? The Champion plugs I replaced were purchased and installed in 2011, and had just under 500 hours on them.
 
On what I consider a more serious side of this, Granted I have been out of the loop on these plugs, But, With the number of planes that "hit the dirt" over the years to partial loss of engine power. Many for reasons never explained. Or were noted to be internal magneto issues. How many might well have been due to spark plug related issues that were design related?
 
Just an anecdote: I recently had a intermittent cylinder head temperature rise (just 25 deg., but not typical) and slight roughness. Eventually, I tracked it down to a spark plug with an intermittent internal resistor. I wiggled the voltmeter probe, pressing fairly hard, and the resistance would vary from 1500 ohm to open. The other plugs were constant at about 1500 ohms. The bad plug also had some yellowish discoloration on the ceramic insulator, presumably lead, but the other plugs were clean. Replacing the plug solved the problem.

I wouldn't have thought of checking resistance before I read the Tempest app note a couple of years ago:
https://www.tempestplus.com/Portals...ht Way to Check Spark Plug Resistors 0213.pdf
 
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Trouble-shooting page from Aircraft Magneto Service's website.

https://www.aircraftmagnetoservice.net/magneto-troubleshooting-guide

Key phrase: Most “bad mag checks” are spark plug related.

Common wisdom is that you can expect about 500 hours of service from massive electrode spark plugs.
In my experience, a Bendix mag will fire a substandard plug long after a Slick will not,
although the engine may still feel rougher than normal.
It's probably a good idea to ohm-meter your plugs at every annual,
and replace them when they peg out at 5000 ohms, per AMS's advice.[SUB][/SUB]
[SUB][/SUB]
 
and the AD or SB issued number was???

or was it just internet theory ???? I don't follow/pay attention to much internet theory...

not saying i don't appreciate the heads up... it makes sense!!

I'm not trying to discourage the discussion. Mike Busch has written extensively on this subject for 10 years now, published in AOPA, Sport Aviation, and numerous other magazines as well as quoted repeatedly after that. I'm just surprised that this hasn't been discussed here before (about 10 years ago), or that this group in particular, whom I consider to be pretty heavy on knowledge and expertise, was not already aware of the issue.

There was no AD or SB as the FAA nor the manufacturer (Champion) considered the problem to be serious enough to require immediate intervention. Champion in particular simply denied there ever was a problem. While some plugs do fail, in most cases the resistance is out of whack. That will cause the mags to run hot, potentially arc internally, or arc across the secondary windings in the coil, especially a Slick Mag, potentially causing a mag to fail prematurely. The resistance checks are something we should be doing any time the plugs are out for cleaning.

-Cub Builder
 
???? Check the instructions for one of your "multi-meters".
but i know web will say this is a good one you can trust, so your not throwing 100 dollar spark plugs away.
never have had one. ebay has em for 5 to 500 bucks. fluke is a popular name.
 
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