Champion spark plugs alert

Watched the EAA webinar about spark plugs the other night that Mike Busch led. Discussion was limited to aviation plugs rather than the automotive plugs that I use, but was surprised to hear that he had a strong opinion that Champion spark plugs should be avoided due to persistent problems with the internal resistor being bad. This results in resistance values way over the optimal 1-2k ohms (up to 5k is ok). At a minimum, resistance values should be checked regularly with these plugs, as there is a potential for some bad juju to occur when the resistance values get real high. Check the webinar for the details. Just thought I would spread the word.

Erich

Their fine wire plugs are even worse. The insulators crack and cause preignition. There have been a handful of Bonanza and TN Cirrus engines destroyed because of this. Tempest plugs dont have these issues.

40 yrs later and some things have not changed.

40 yrs later and some things have not changed.

Back in the 70's when we were still running points and condensers and were Hot Roding around in our 440's and 383 Magnum as well as the hi strung 340, the best we could get out of the Champion Plugs were around 10,000+- miles. At that point they looked ok but they would start missing and we would have to can them.

Switched to Autolite or AC and we could easily get 15,000+ miles on them.

And you should see the rubbish they have been publishing, and writing to individuals.

Byron will no doubt see this soon enough and have his $0.02 worth on their stupid head in the sand stance.

Not the same company

Champion automotive and Champion aviation are not the same company. AC doesn't make plugs. Champion and NGK makes most of their plugs. Every Chrysler comes with Champion plugs so I guess all these Chryslers are getting plugs ever 10K miles. Do your home work before painting with a wide brush. I raced a Ramcharger Dodge with Champions and today several top fuels run Champion.

Run like @#*% from Champion... they are Crappppiest plug available today in the aviation world of spark plugs!!!!!!!!!!!!!!!!

The word concerning out-of-spec resistance has been circulating for a while. We've certainly found some high resistance Champion plugs at our airport; the local A&P has a nice collection. On the flip side, it is not universal. I just checked mine at annual, 225 hours. They were all 2-3K except for one at 4K.

High resistance in a massive electrode plug causes misfire, and it is also hard on magneto coils. Not desirable, but not dangerous. The failing center insulators on the fine wire plugs is a whole different problem.

Two years ago I purchased 4 new Champion plugs. Two failed within 50 hours. I called them and it took them three months to replace them. I am a firm believer in Tempest now for plugs and oil filters.

At 90 hours (during the last annual) I replaced one plug that measured a little over 5k, this cured a mysterious stumble that happened occasionally when operating below 60% power. It also cured what seemed to be a fouled plug on run up that I could 'clear' by leaning.

This plug along with all the rest showed no evidence of carbon or lead deposits beyond a thin light grey flashing that I presumed to be normal.

DanH said:

The word concerning out-of-spec resistance has been circulating for a while. We've certainly found some high resistance Champion plugs at our airport; the local A&P has a nice collection. On the flip side, it is not universal. I just checked mine at annual, 225 hours. They were all 2-3K except for one at 4K.

High resistance in a massive electrode plug causes misfire, and it is also hard on magneto coils. Not desirable, but not dangerous. The failing center insulators on the fine wire plugs is a whole different problem.

Click to expand...

Dan, Give then another 100-150 and you will be in the zone of when they start drifting.

Over 1,400 hours

I got over 1,400 hours on my Champion Massive Electrode Spark plugs before replacing them. They never missed a beat and were still serviceable when I removed them for UREM37BY plugs.

It sounds to me like a lot of people are mishandling their spark plugs. Once you drop them, they go in the trash and not back in the airplane.

Aircraft Sparkplug Service in Van Nuys CA.

I see the ad in Trade-a-Plane, and when I bought the T-18, it included service cards from them, to send in plugs for reconditioning.
Do they (Jeanne?) replace the massive or the resisitor or anything?
The reviews are all good, I just wondered what the scope of the work is, and if a bad resistor can be replaced, or a dropped plug repaired?

Thermal cycles affect life span of cylinder heads as well as spark plugs. I would bet that those that are careful operating their engine and fly long xc's will have longer plug life. One reason for having redundancy.

Just about rotating my Champion spark plugs (I have two sets) which I rotate at each oil change or 50 hours. Checking the resistance, they all came at 1.1 and 1.2K. These sets have roughly 200 hours on them.

I recently removed a set of REM-40 plugs from my SNJ. They had served me well for about 12 years, and about 1000 hours. They never missed a beat, but were well-worn, i.e. the center electrodes were no longer round, but were very much like a football.

I tested them with a cheap ohmmeter, and about half of them showed high resistance, with two showing "open". But they were working great when removed.

I spoke with a Champion rep at the Reno Air Races this year, and asked about the resistance thing. His answer was that the resistor is made to show the proper resistance whenever a high-voltage pulse is present, and can't necessarily be measured properly with a 9-v ohmmeter.

He said the proper way to test a spark plug is on a spark plug testing machine (Bomb Test). If it functions well on the bomb test, should work well in the airplane.

(Don't shoot the messenger, just passing his comments along.)

Over 600 hours on my massive stock Champions. Every 50 hours clean up, rotation and regap no degradation in performance noticed. I take every alert seriously and will keep close watch on them.

PCHunt said:

I recently removed a set of REM-40 plugs from my SNJ. They had served me well for about 12 years, and about 1000 hours. They never missed a beat, but were well-worn, i.e. the center electrodes were no longer round, but were very much like a football.

I tested them with a cheap ohmmeter, and about half of them showed high resistance, with two showing "open". But they were working great when removed.

I spoke with a Champion rep at the Reno Air Races this year, and asked about the resistance thing. His answer was that the resistor is made to show the proper resistance whenever a high-voltage pulse is present, and can't necessarily be measured properly with a 9-v ohmmeter.

He said the proper way to test a spark plug is on a spark plug testing machine (Bomb Test). If it functions well on the bomb test, should work well in the airplane.

(Don't shoot the messenger, just passing his comments along.)

Click to expand...

The problems will readily show up if the plugs are high resistance, and when running LOP, and have a slightly larger than normal gap. Some last longer than others, it seems random.

As for Bomb testing, this is NOT proof the plug will work fine in an engine. We have prooven this by taking a known to be failed plug, and bomb testing, then heating it to 420F and testing again. Tested perfect. Put in an engine where the pressures are much higher...FAIL!

So don't assume if it tests well it is well!

"I spoke with a Champion rep at the Reno Air Races this year, and asked about the resistance thing. His answer was that the resistor is made to show the proper resistance whenever a high-voltage pulse is present, and can't necessarily be measured properly with a 9-v ohmmeter."

His statement is only remotely true if there is an open circuit inside the plug in series with the resistor that is acting as an spark gap at high voltage. If this occurs there is energy being wasted in arcing across the gap, possible damage being done because of high temperatures and ionized air across this gap, and deteriorating performance of the plug as a result. I would think this could also cause damage to the magneto coil and result in increased radio noise as well.

Not a good situation at all.

I would think this could also cause damage to the magneto coil and result in increased radio noise as well.

Click to expand...

This has been published decades ago.............

Champion are ducking weaving and burying their heads in the sand. Sad to see.

RV10inOz said:

Dan, Give then another 100-150 and you will be in the zone of when they start drifting.

Click to expand...

You were right. Previous annual at 225 hours. At that time they were all 2-3K except for one at 4K. This time, at 315, only one checked at ~2900 ohms, with the rest being far higher to infinity. The lowest was about 9K. I even installed a new battery in the trusty Fluke just to make sure of apples-to-apples meter power.

Had two almost new Champions with less than 50 hours on them fail in the same cylinder on the same flight in my old Cherokee. Switched to Autolite/Unison/Tempest UREM37BY plugs and never looked back.

Just pulled my HIGH DOLLAR fine wire Champions (REM38s) from the bottom positions on my RV -- LS PIII on top with $2 NGKs/Slick 4371 with $90 each fine wire champions on the bottom. I did this due to an unacceptable mag check trend. Checked the four fine wires with an ohm meter--3 of the 4 would not read at all (open circuit) while one was still in spec at 1400 ohms. Ordered a set of Tempest massives at $23 each (AC Spruce) to replace these bad boys. Just hope the mag coil has not taken too bad a beating.

Cheers,

db

RV10inOz said:

And you should see the rubbish they have been publishing, and writing to individuals.

Byron will no doubt see this soon enough and have his $0.02 worth on their stupid head in the sand stance.

Click to expand...

I posted an email but I erased it. Basically they blame detonation from running too lean, those guys in Ada trying to sell their GAMI injectors.

I had two champion plugs go bad at 75 hours on my first plane and have been a Tempest guy for years now. I've switched to Tempest Oil filters too just to get away from champion. I found a place that ships free online. qaa.com prices are good and I get my tempest shipped free to my shop, hassle free.

I know the VP of Marketing for Tempest and I saw him at Aircraft Spruce when they had their big sale in the fall.. I seem to recall him telling me their plugs were guaranteed (at least in the respect of testing bad on resistance). If one ever failed they would replace it. I can double check with him if you guys want me to..

bkilby said:

I know the VP of Marketing for Tempest and I saw him at Aircraft Spruce when they had their big sale in the fall.. I seem to recall him telling me their plugs were guaranteed (at least in the respect of testing bad on resistance). If one ever failed they would replace it. I can double check with him if you guys want me to..

Click to expand...

And I would be they can replace faster than Champion

RV6_flyer said:

I got over 1,400 hours on my Champion Massive Electrode Spark plugs before replacing them. They never missed a beat and were still serviceable when I removed them for UREM37BY plugs.

It sounds to me like a lot of people are mishandling their spark plugs. Once you drop them, they go in the trash and not back in the airplane.

Click to expand...

Gary glad to see I am not alone satisfied. I am very happy with Champion Massives and I still keep originals on top after 1K hours. Never missed a beat. Will be ordering a new set (8) soon exactly the same model. Dropped couple of them and replaced with shiny Tempest. They already turning rusty but performing great. Yes I have a mix


1,000 hours Champion. Picture of electrodes will be added in couple weeks.








120 hours Tempest. For those who like polished maybe not a great choice.

Vlad said:

Gary glad to see I am not alone satisfied. I am very happy with Champion Massives and I still keep originals on top after 1K hours. Never missed a beat. Will be ordering a new set (8) soon exactly the same model. Dropped couple of them and replaced with shiny Tempest. They already turning rusty but performing great. Yes I have a mix


1,000 hours Champion. Picture of electrodes will be added in couple weeks.








120 hours Tempest. For those who like polished maybe not a great choice.

Click to expand...

Vlad,

My name is John Herman and I am President of Tempest Plus Marketing Group, LLC. I noticed you have had an issue with corrosion on your Tempest plugs. When we acquired the product line from GE (Unison), our goal was to improve on a product we felt was already of very high quality. One of the areas we felt we could improve was the plating material and process due to some reports of corrosion. We have since made the necessary improvements and are happy to report very good results in reducing corrosion. I will be honest, the only way to totally eliminate corrosion is to go to a stainless steel and that is cost prohibitive. However, I believe you will be vary satisfied with the improvements.

If you will please email me your contact information I will be happy to resolve the issue you are having to your satisfaction. My email address is [email protected].

Thank you for your business and support. Look forward to hearing from you soon.

nice message John.....

or......how to score points with about 5,000 current and potential customers here on VAF!

How many of you guys rotate the plugs from positive to negative firing, to even the wear on the electrode? ( ....... you'd have to to get 1000 hours eh?)

Seems some folks feel this is a fallacy, I would think it's either true or false based on how the magneto distributes current.

Somebody way smarter than me can set us straight!!

Nope

Since electron flow is from the negative to the positive, the plugs' current flow path is always from the ground electrode to the center (positive) post.

Swapping them doesn't reverse current flow.

Best,

Welcome to VAF!

jcherman said:

My name is John Herman and I am President of Tempest Plus Marketing Group, LLC.

Click to expand...

John, welcome to VAF

Always good to see representation from those folks we do business with, taking a part here.

Good to have you aboard, and get ready to answer questions, pretty sure there will be some shortly.

Vlad

Check those Champion plugs for high resistance. There is evidence that suggests that this may be one of the reasons for coil degradation due heat stress.

And for everyone watching....... John Herman is the real deal. Good bloke and delivers on customer service.

welcome JH.

and this is the funny part......FWIW

pierre smith said:

Since electron flow is from the negative to the positive, the plugs' current flow path is always from the ground electrode to the center (positive) post.

Swapping them doesn't reverse current flow.

Best,

Click to expand...

Pierre, I totally agree with your theory....so of course, there has to be another equal and opposite polarity...I mean...explanation....because these things are just like that!

John at SacSkyRanch, who is considered by some to be a good source of info.....has the following commentary.....


The following discusses the advantages of rotating spark plugs to positions of opposite polarity. It was written by John Schwaner of Sacramento Sky Ranch. For more information you can contact him at (916) 421-7672, or visit their website at www.sacskyranch.com.

Why Rotate Spark Plugs?


Here is a method of plug rotation that not only swaps plugs from top to bottom, but also swaps from short lead to long lead, and reverses spark plug polarity. This method works with most horizontally- opposed engines.

For a six-cylinder engine move plugs:
1T to 6B
2B to 5T
3T to 4B
1B to 6T
2T to 5B
3B to 4T

For a four-cylinder engine move plugs:
1T to 4B
2B to 3T
1B to 4T
2T to 3B

Spark plug life can be just about doubled by proper plug rotation. Look at the spark plug electrodes the next time you remove the spark plugs from your engine. One electrode is usually worn more than the other. On one plug, the center electrode may be worn, while on another plug, the ground electrode may be worn. Swapping plug position evens out the wear between the center and ground electrode, thereby preventing any one electrode from incurring excessive wear.
The spark plug?s firing polarity causes uneven electrode wear. The magneto generates energy by means of a rotating magnet. As the magnet rotates, the magnet?s north and south poles generate positive and negative electromotive force. The magneto sends a positive voltage down one lead and a negative voltage down the next lead and so on. Each ignition lead always fires the same voltage (on horizontal-opposed engines), but the voltage alternates among leads. (D-2000/D-3000 magnetos on 4-cylinder engines always fire at the same polarity). Current flow, from the spark plug?s cathode electrode to the anode electrode, causes the cathode electrode to wear.
To equalize wear, move the spark plug to a different position so that it fires at the opposite polarity. Do this by swapping the spark plugs with worn ground electrodes with the plugs that have worn center electrodes. You may also move the spark plug to the next lead position coming out the back of the magneto. Spark plugs also wear unevenly due to differences in lead salt deposits and ignition lead capacitance. The higher wear rate on spark plugs operating on avgas than on autogas is due to lead salt corrosion from the lead in avgas. Swapping plugs from top to bottom helps equalize wear caused by lead salt corrosion.
The greater the ignition lead?s capacitance, the more current flows across the spark plug gap and the more the plug electrodes wear. Shielded spark plug leads, having an insulator separated by two conductors, act as linear capacitors. Approximately 25 percent of the energy sent to the plug from the magneto is used to charge the lead?s capacitance. Once the lead is charged, the voltage across the spark plug electrodes increases until a conductive path forms between the ground and center electrodes and the plug fires. The conductive path completes the electrical circuit between the lead?s center conductor and the ignition lead shielding. Capacitance energy stored in the lead then discharges across the spark plug gap after the original arc. Usually, the spark plug has already lit-off the fuel/air mixture, so this capacitance energy is of no use except that it causes electrode wear. The longer the lead, the greater the capacitance, and the more the electrode wears. Swap spark plugs between short and long leads to equalize wear caused by lead capacitance.

jcherman said:

Vlad,

My name is John Herman and I am President of Tempest Plus Marketing Group, LLC. I noticed you have had an issue with corrosion on your Tempest plugs. When we acquired the product line from GE (Unison), our goal was to improve on a product we felt was already of very high quality. One of the areas we felt we could improve was the plating material and process due to some reports of corrosion. We have since made the necessary improvements and are happy to report very good results in reducing corrosion. I will be honest, the only way to totally eliminate corrosion is to go to a stainless steel and that is cost prohibitive. However, I believe you will be vary satisfied with the improvements.

If you will please email me your contact information I will be happy to resolve the issue you are having to your satisfaction. My email address is [email protected].

Thank you for your business and support. Look forward to hearing from you soon.

Click to expand...

John thanks. Maybe I worded it wrong, English is my third language but I am OK with the Tempest plugs. I bought them a year or so ago and they never missed a beat either. I fly all year around and as one of my buddy would say - could slowly run a hardware to its physical end... so those tiny rusty spots are OK with me. You should see some other spots on my unpainted non primed airframe.

I was introduced to your product in funny way. I was finishing an inspection and dropped one of my Champions. No crack was visible but the Champion run rough on high RPM. I had to fly someplace and borrowed a new plug from our flight school mechanic. It was shiny Tempest then I ordered four new from Spruce. Returned one and installed the rest on the bottom. Run great. Give me a stainless and I will corrode it too

pierre smith said:

Since electron flow is from the negative to the positive, the plugs' current flow path is always from the ground electrode to the center (positive) post.

Swapping them doesn't reverse current flow.

Best,

Click to expand...

Actually it does. Ground is not always negative with respect to current flow. The rotor in the magneto generates alternating positive and negative pulses relative to ground. Each plug in the firing order receives a pulse opposite in polarity from the previous one.

Plug resistance is changing.

Can any one tell me what actually causes the increase in plug resistance? Is it corrosion of the actual resistor, physical damage or something else. I have all 6 lower fine wire Champion plugs showing high resistance. (9 to 37k ohms) AND this is the second set of bottom plugs that have done this. The top ones are all fine and don't seem to be having the problem.

Any help would be much appreciated.

RV 10 with a IO-540

FWIW, a couple of years ago at the Reno Air Races, I spoke at length with a Champion rep, at their booth in the pits.

He explained to me that the resistor in the Champion plugs was designed for very high voltages, and could not be measured properly with a standard low voltage ohmmeter.

He further stated that the way to check the plugs was with a "bomb" tester, which applies air pressure. If the plug sparks properly on the tester, it is good for flight.

If your engine is running well at all power settings, why change plugs?

I used a set of Champion plugs in an R-1340 for about 15 years. Bomb tested them every annual, never checked the resistance. The center electrodes finally wore out. I have a mixture of Champions and Tempest now. Some of the Tempest plugs were difficult to get threaded into the engine.

My two farthings..............YMMV, etc.

ednetherton said:

Can any one tell me what actually causes the increase in plug resistance? Is it corrosion of the actual resistor, physical damage or something else.

Click to expand...

A very good question.

PCHunt said:

FWIW, a couple of years ago at the Reno Air Races, I spoke at length with a Champion rep, at their booth in the pits.
He explained to me that the resistor in the Champion plugs was designed for very high voltages, and could not be measured properly with a standard low voltage ohmmeter.

Click to expand...

Sure, given enough voltage the electrons will overcome a resistance measured as infinite with an ohmmeter, the spark plug electrode gap being a fine example.

When the secondary discharges, voltage rises until it reaches a level high enough to jump the plug gap....at 0.018" and normal pressures, about 14,000V, give or take. The gap resistance then falls to a low level as the gas between the electrodes is ionized.

If initial resistance at the spark plug is higher than at some other point in the secondary circuit, the electrons take the easier path. The alternate path can many forms; I'd guess flashover inside the rotor housing or insulation breakdown in the coil are the most common.

So much for the basics, so let's theorize a bit. It would seem that with a new plug, the voltage potential must rise enough to pass the sum of the gap resistance and the moderate fixed internal resistance. If the fixed resistance rises in long term service, the total initial voltage requirement must also rise. The alternate breakdown paths become more viable, which is not a good thing.

The Champion guy seems to be saying their internal resistor is somehow variable, like the ionized gap; resistance is very high until high voltage can establish current flow. However, there is still a high initial voltage requirement (which seems to be getting higher as the Champions age), and anyway, is there a solid resistor with such behavior?

Fly with the best. Fly TEMPEST!

I had several plug related questions. I emailed John Herman and got all of them answered. I sent two worn offending spark plugs to their engineering department and in a week or so I received brand new ones.


These are some suggestions from John:

....There are however a couple of other things I would suggest to you for future installation:

1. Always replace the copper gasket with a new one every time the plugs are removed. The gasket flattens once the torque is applied and it can never be reused and take the appropriate shape. Also, copper has heat sync properties which assure the heat from the plug core nose is dissipated properly. Improper heat dissipation effectively changes the heat rating of the plug and can, in severe case, cause pre-ignition...


2. Anti-seize compound on the spark plug threads is also very important. Not only does it allow easier removal of the plugs, but jt also assures proper torque when installing the plugs...

3. Be sure your torque wrench is calibrated at least annually. The assurance of proper torque is very important for not only securing retention of the plug, but also again to insure proper heat sync of the spark plug core nose temperature.

Click to expand...

I installed them right away brand new and they never missed a bit. That's how they look after almost 200 hours.





On Cyl#2 occasionally some oil makes its way inside that's why bottom plug is wet when removed from cold engine.






Great customer support from TEMPEST excellent product thanks from a happy customer!

Champion rem38E- Is it Bad?

During my recent condition inspection I tested the resistance of the plugs and using a cheap Radio shack volt/ohmeter, all were in the 1.5K range except one that showed very high resistance (barely a movement of the needle). I replaced it but later, got a screwdriver and turned the screw in the indentation, opposite the electrodes and now the resistance shows about 1.5K. What's the deal with this screwhead and did I 'fix' the plug? Hate to throw it away if tightening the screw fixed it?????

Jim Diehl 7A
Lock Haven, Pa.

Last annual I complained about a cylinder with a sticking valve. It warmed up during taxiing and the run up and would be fine before I checked the mags. It stayed fine during flight. The AI bore-scoped the valve and said that the valves were fine and that it was probably the spark plug. I changed plugs and the problem went away.

I measured the resistance, cold, of the twelve plugs and they were all over the place. Resistances above 20k ohms were common. But they work fine. This cylinder had one low resistance and one high resistance plug; replacing them both cured the issue.

I concluded that measuring resistance, at least on cold spark plugs, isn't worth much. Having an all-cylinder egt gauge is worth a lot.

Dave

Champion failure

I maintain a dozen airplanes for a flight school. Champion massive plugs (REM38E)worked fine with an average failure rate for many years. Then 3-4 years ago the failure rate started to climb quite dramatically. We started to regularly pitch full sets of plugs due to incurable rough running on plugs with less than 1/2 electrode wear. We switched to Tempest massive plugs (UREM38E)and normal operation resumed. We still occasionally get Champions that were installed by a contract vendor and they never seem to last. We disassembled several malfunctioning Champion plugs (just use a flat head screwdriver and remove the internal plug) and found what appeared to be heavy oxidation/deposits on the spring and resistor element. The deposits were similar to what you find on a worn out distributor cap contact. So anyhow I wonder if Champion tried to save a few cents with lower grade internal components resulting in internal arcing that results in wear and an increase in resistance. It would be nice if the Champions of the past would return because even though I like Tempest competition from competitive products is good for the market. my.002 Russ

REM38E

Thanks for the comments Russell. I learned a bit a about the inside of a Champion plug. I removed the screw and a spring and graphite rod dropped out. Other than minor graphite dust, it looked good. I put it back together and set the screw tight. The resistance is now about 1.5K-similar to the others. The plug came out of my factory new Lycoming 0-360 with 125 hrs TT. Any reason i can't use it as a spare?
Thanks,

Jim Diehl 7A
Lock Haven, Pa.