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PMAG Problem

G

gbusterguy

Member
I recently had a problem with my PMAG. Some facts; I have a RV7, Superior IO 360, One Mag and one PMAG serial No. 1775, installed over 2 years ago, I have a standard Bob Knuckles electrical system design, and a B&C alternator.

We were flying at 7,500?, Good Wx, smooth air, lean of peak. Suddenly the engine began running very rough simultaneously the alternator light illuminated. I immediately richened the mixture which didn?t change the roughness. We began to notice an electrical burning smell, not a good sensation. I activated the emergency bus, turn off the master switch and punched in nearest airports in the 430 GPS. The smell dissipated.

We then noticed that the cylinder head temps were in the red. Was this for real or part of an electrical issue? I checked the oil temp., it was above normal. We reduced the power to 42% which was enough to maintain our altitude. The cylinder head temps returned to the green. The engine roughness continued. We considered a mag check but thought it best to leave out that option for fear of making things worse. We pressed on to KUKL, home base at a 130 kt ground speed.

Once on the ground I did a mag check, the engine ran fine on the mag but would not run on the Pmag. We found the connector on the end of the power wire coming off of the alternator had broken after 10 years of vibration and had been arching between the wire and the alternator, thus the elec. burning smell. We found the Pmag timing was out. I was able to retime it following the Emag instructions.

What happened? A clue was found on the Emag website under ?Tips and Tricks.? It says to be sure that your Pmag is off when you charge your battery because the pulsing or cycling of some battery chargers can scramble the timing of the Pmag. It seems that perhaps an electrical pulsing in flight can have same effect on the timing.

Fortunately this happened in good Wx at a relatively high altitude, I have a 4 cylinder EMS and I was flying with another pilot who was a huge help in sorting thing out, and I only had one Pmag.

The Pmag has been sent back to the manufacturer for evaluation. My engine has been inspected for damage by a very competent aircraft mechanic. It has been determined that the rings got hot enough to lose their temper; one cylinder has some scrapes on the cylinder wall. I am replacing that cylinder, rings and all 4 pistons as a precaution. I haven?t given up on EI but I am going to put my mag back on until all this timing business gets resolved.
 
You did a great job of getting things sorted out. Switching to one mag, then the other would have identified the problem mag.

The Pmag should be operating exclusively on internal power at that RPM unless is was the older Emag version (non-self powered).

What version of Pmag?

Bevan
 
Unless that P-Mag has the latest firmware, it will still be susceptible to losing its timing if powered up and down while the engine is running. Version 40 firmware is a "must have" for P-Mags. Some P-Mag owners think they don't need the newest firmware because their cockpit switching technique removes the possibility of them inadvertently power-cycling the P-Mag with the engine running. Unfortunately that line of thinking doesn't cover some of life's other little eventualities, like stuff that happens beyond our control, and the control of our ignition switches.
 
Nice to know the experts!

....okay, it's refreshing to know when 2 of the smartest guys I know BOTH pitch in and post when there's a problem! :)
....and I don't even have a P-mag........yet!
 
Perplexed?

Hi

I have read this with interest as I have two Pmags, and can I congratulate you on your diagnostic work on working out what caused the problem with your P Mag. I will certainly make sure I check the connections on my alternator to make sure this does not happen to my system.

Also good decision making in your actions to ensure a safe flight and return to the ground. I had a very similar experience with a Lightspeed EI. It popped the circuit breaker for no apparent reason. CHT and EGT rose. It would not reset so I carried out very similar actions to you, got the temps down and landed.

I checked all my wiring and found no fault and after resetting things on the ground it all worked again, however several hours later the EI developed a misfire which I could not cure, hence my change to dual P mags.

I wonder why though you have titled this as P Mag problem. What you had was a problem with your alternator connections which apparently caused a timing shift on your P Mag. The Pmag was apparently happily doing its job and would have continued to do so had the alternator connection not failed?


It's great to know that the failure mode of PMags with certain chargers can be replicated by an arcing alternator connection and Emagair should in my opinion include this information in their manual so that the connection gets checked. I have now added it to my list of repetitive checks in my engine log book, so again thanks for that.

I am though perplexed as to why you seem to be identifying the PMag as the culprit when it was in fact the victim of a wiring fault. I guess if it gets the brains at Emagair to come up with a solution to prevent this failure mode then that will be great, but all us P mag owners can do to prevent a similar failure is to ensure the integrity of our charging system.

Thanks again for posting this, it really is good information to have and could save a life. Actually come to think of it I am glad you posted it as PMag problem or I might not have read it. Well done try to ensure Emagair include this failure mode in their manual!
 
Solution?

Canadian_JOY said:
Unless that P-Mag has the latest firmware, it will still be susceptible to losing its timing if powered up and down while the engine is running. Version 40 firmware is a "must have" for P-Mags. Some P-Mag owners think they don't need the newest firmware because their cockpit switching technique removes the possibility of them inadvertently power-cycling the P-Mag with the engine running. Unfortunately that line of thinking doesn't cover some of life's other little eventualities, like stuff that happens beyond our control, and the control of our ignition switches.
Click to expand...

Does this mean that V40 pmags would not suffer this type of failure mode?
 
Just a quick reminder to check emag website for service notes. I just had an emergency in flight and would have benefited greatly from seeing this before hand, reference case bolts on pmag in my case. More to follow once I get the plane flying again.


http://www.emagair.com/service-notes/
 
Canadian_JOY said:
Unless that P-Mag has the latest firmware, it will still be susceptible to losing its timing if powered up and down while the engine is running. Version 40 firmware is a "must have" for P-Mags. Some P-Mag owners think they don't need the newest firmware because their cockpit switching technique removes the possibility of them inadvertently power-cycling the P-Mag with the engine running. Unfortunately that line of thinking doesn't cover some of life's other little eventualities, like stuff that happens beyond our control, and the control of our ignition switches.
Click to expand...

I can't stress enough how important the Version 40 upgrade is, if you have a mixed ignition environment and/or use toggle switches to ground your P-mags.

WAM120RV said:
Does this mean that V40 pmags would not suffer this type of failure mode?
Click to expand...
Yes, that is what this means.

It turns out that pre-version 40, when the P-mags are powered (or spinning above 800 RPM) and they are grounded, they are in setup mode. Which means two puffs in the manifold line will change their TDC mark to wherever the crankshaft is when the P-mags get the puffs.

With the shorting described by the OP, the system was being grounded, which puts it in setup mode. (Powered but grounded is setup mode.)

When your intake valve closes there is a short duration but high velocity positive pulse in your manifold pressure line, just like the puff it takes to set the timing.

Version 40 is different in that the prop must be stationary to set the timing. Thus a spinning P-mag will not allow its timing to be changed.

So to answer the question, this problem was solved in late 2014, so depending on the vintage of your P-mags, you want to get them in for the update.

Here is the link to the Emag Service Notices. While they don't list it as "mandatory", our experience is that it is required. Think of it like a certified airplane's Service Bulletin vs. AD.

gbusterguy, check your PM's.
 
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N941WR said:
It turns out that pre-version 40, when the P-mags are powered (or spinning above 800 RPM) and they are grounded, they are in setup mode. Which means two puffs in the manifold line will change their TDC mark to wherever the crankshaft is when the P-mags get the puffs..
Click to expand...
So, if I understand this right, when you do your run up, and individually ground out the PMags to test the RPM drop, this inadvertently puts the PMag in setup mode as long as the P Lead is grounded out? This seems to be quite different from what Emagair put on their website...please clarify.:confused:
 
Mark Dickens said:
So, if I understand this right, when you do your run up, and individually ground out the PMags to test the RPM drop, this inadvertently puts the PMag in setup mode as long as the P Lead is grounded out? This seems to be quite different from what Emagair put on their website...please clarify.:confused:
Click to expand...

There is a difference, and I'm not sure how to address it properly.

What we found is that in startup mode (below 200 RPM), it is very possible to reset the timing, IF one P-mag is in setup mode and the engine cranks over.

Now, to answer your question, once the engine comes out of "startup" mode (above 200 rpm), it should not be possible to reset the timing. However, with the OP's situation where there is some shorting event going on, all bets are off.

If a mag check were able to reset the timing, there would be many more lost timing issues than we have heard about.

The lost timing event that V40 addressed typically happens with ignitions of different types or two P-mags operated by toggle switches and a P-mag is left grounded for starting. When this happens, we found there is about a 40% chance of resetting the TDC mark.

Timing with Version 40 is slightly different, you have to set the prop to TDC and then power up the P-mags. If the prop turns after the P-mags are powered up, you cannot reset the timing, regardless of the RPM.

The other change that V40 has is to fire the plugs at 4 degrees AFTER TDC for starting. Pre V40, they fired the plugs at TDC. Thus you do not have to "clock" the P-mags, if you have a lightweight prop.

I hope all that is clear.
 
Thanks Bill Repucci

Bill

Thanks for clarifying this, so bottom line is that this would not have happened if V40 had been installed?

In which case it still makes sense to check your leads, but the potential problem has already been sorted by EMagair, provided the mags are upgraded to V 40?

If any of you have not realised Bill is a great asset to this board!!!
 
WAM120RV said:
Bill

Thanks for clarifying this, so bottom line is that this would not have happened if V40 had been installed?

In which case it still makes sense to check your leads, but the potential problem has already been sorted by EMagair, provided the mags are upgraded to V 40?
Click to expand...

Correct, or as correct as I understand the issue and the solutions we have helped others work through can be.

The real answer is that Emag (the company) has the final say on what does and does not work with their P-mags (the product), not some guy who makes a bolt on (The EICommander) for them.

WAM120RV said:
If any of you have not realised Bill is a great asset to this board!!!
Click to expand...
I'm not so sure about that, but thanks!
 
Title is pertinent!

I have to agree with the poster about the choice of title for a couple of reasons. First, It will alert P-Mag owners to a potential emergency, and motivate them to get the update. Secondly, The P-Mag is supposed to be a drop in replacement for a standard mag,,, with the understanding that a loss of power is an inconvenience, not an emergency (at least in the sense that you're not going to enjoy a forced landing).

BTW, I put them in the 8A I built and loved them. So, I'm not against EI at all. In fact I'll be using the EFII in the new plane, primarily because I wanted single lever fuel injection too.
 
N941WR said:
I can't stress enough how important the Version 40 upgrade is!


Yes, that is what this means.

It turns out that pre-version 40, when the P-mags are powered (or spinning above 800 RPM) and they are grounded, they are in setup mode. Which means two puffs in the manifold line will change their TDC mark to wherever the crankshaft is when the P-mags get the puffs.

With the shorting described by the OP, the system was being grounded, which puts it in setup mode. (Powered but grounded is setup mode.)

When your intake valve closes there is a short duration but high velocity positive pulse in your manifold pressure line, just like the puff it takes to set the timing.

Version 40 is different in that the prop must be stationary to set the timing. Thus a spinning P-mag will not allow its timing to be changed.

So to answer the question, this problem was solved in late 2014, so depending on the vintage of your P-mags, you want to get them in for the update.-------------------



Good explanation. Thanks. Good to know why instead of just do it. Larry
Click to expand...
 
The next question is, "How do I know what version I have?"

The software fix came out in the fall of 2014. So, if you have had your P-mags back for a check up, they will have been upgraded to V40.

If you bought your P-mags prior to that and have not had them back since late 2014, you probably do not have V40.

1. There should be a sticker on the P-mags that list the version number, hopefully you can read it.

2. Put the P-mags in setup mode (powered AND grounded), move the prop to TDC and blow in the tube twice, observing the LED. If the P-mags let you set the timing you do NOT have Version 40. (Version 40 will not let you set the timing if the prop moves after being put in setup mode.)

3. If not, then you can connect to each P-mag with a PC via the P-mag's serial port (Pin's 2 & 3) and query them via the free EICAD program, available on the Emag website.

4. You can query them with an EICommander.

Those four options are listed in the order of expense.
 
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one more observation

Just a quick observation. I would not be hesitant to shut down the offending ignition source in flight. Thinking that it might be worse... just continues the rough operation. Planes fly just fine on one. Check left and right when roughness occurs. Then shut off the bad one. Simple and safe. You did go richer, which was probably a good move. Switching tanks to rule out contamination might be prudent also. Glad this thread go started... and I think most of us are fine with the title.
 
We suspected an ignition problem and we were mostly concerned about turning off the good one and creating a strong backfire situation that could do more damage. Right or wrong that was the thinking. I do however understand the conventional thinking behind the mag check but it was running, not great but moving us along. We decided if it got worse we would do the mag the check. Since overheating was occurring fuel didn't seem to be the problem but I agree switch the tanks was in order. I will say that having another very experienced pilot in the cockpit to think through this compound emergency situation was extremely helpful. It's sobering to think about the flight just prior to this one, it was at night with my wife!
 
p mag

Sounds like the P mag company needs to pay to fix this guys engine if he was not notified of problem.
Bob
 
spouses

Loal, it might not be practical... but a pinch hitter course for your wife might be something to look into. As you mentioned, having someone else to bounce ideas off of always helps. I started out just intending to have my wife get familiar. Eventually she passed the PPL test. She is far more engaged in all flights now. Though she has not flown the RV solo... just the Cessna trainers, she understands how they work.
I probably would have done just what you did. Having had a long list of inflight emergencies... I have had the "benefit" of trying out different things. Monday morning quaterback data base if you will. I had a very experienced B 17 pilot with me the time a plane caught fire inflight. He really helped. We got it on the ground gear up and ran like ****. It burned to the ground.
Anyway, I always switch tanks... richen the mixture... pull the rpm back, and then do some diagnostics. Somewhere in that flow is punching the nearest airport button on the GPS. Many pilots stay in the air far too long when working out a solution. A task much better suited to the ramp. Have a great holiday and hope future trips are much smoother.
 
Wow....thanks! I'll update later.

That inflight fire stuff scares me just thinking about it! Thanks for the tip on getting my wife up to speed on flying. I've tried that in the past and couldn't get her interested, I'll try again, I think it's a great idea.

I'll report back after the Emag guys do their evaluation.
 
GalinHdz said:
6 Gun said:
Sounds like the P mag company needs to pay to fix this guys engine if he was not notified of problem.
Bob
Click to expand...

Sounds like somebody should not be in the experimental aviation world.
:cool:
Click to expand...
Let's think about this.

During the last Condition Inspection the Emag site was not checked for current service bulletins, which might have prevented the issue.

Then the aircraft in question had some shorting wires under the cowl, which may have (or may not have) caused the lost timing.

The pilot could have switched off the P-mag. Having a mixed ignition, that would be my first guess.

How are either of those two issues or the fact the pilot did not do a mag check the Emag company's fault?

Yes, it is a bummer that Loal is going to foot the bill for this.
 
Whitman said:
Just a quick reminder to check emag website for service notes. I just had an emergency in flight and would have benefited greatly from seeing this before hand, reference case bolts on pmag in my case. More to follow once I get the plane flying again.

http://www.emagair.com/service-notes/
Click to expand...

This is the problem Whit referred to; four internal screws that apparently didn't get locking agent when assembled. As a result, his p-mag was coming apart in flight.

 
N941WR said:
Let's think about this.

During the last Condition Inspection the Emag site was not checked for current service bulletins, which might have prevented the issue.

Then the aircraft in question had some shorting wires under the cowl, which may have (or may not have) caused the lost timing.

The pilot could have switched off the P-mag. Having a mixed ignition, that would be my first guess.

How are either of those two issues or the fact the pilot did not do a mag check the Emag company's fault?

Yes, it is a bummer that Loal is going to foot the bill for this.
Click to expand...

And lets also think about:

I thought the whole point of having an internal power supply was to prevent external electrical failure from shutting down the PMAG?

If the engine starts runnning rough, you have a lot on your plate, doing a 'MAG' check probably isn't the first thing that is going thru the pilots mind, so don't blame him.

I also take exception to the casting of aspersions on the last guy to do the CI, SB's are advisory in nature and not mandatory in any maintenance program I'm aware of (91, 125, 135, 121), blaming that guy for the failure of the PMAG is just not not cool.
 
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Walt said:
I also take exception to the casting of aspersions on the last guy to do the CI, SB's are advisory in nature and not mandatory in any maintenance program I'm aware of (91, 125, 135, 121), blaming that guy for the failure of the PMAG is just not not cool.
Click to expand...

I think the idea is that the PMag wasn't solely to blame for the issue and was subjected to an environment outside it's design parameters. Frankly, I'm skeptical that such a failure could cause the timing issue and think maybe switchology might have been involved otherwise it's not clear how a powered-and-ungrounded PMag could revert it's timing.

And I could be completely wrong - or I could be completely right. Because that question exists, placing all the blame on the PMag is specious - and I think that is what Bill is getting at. I'd add only that he's not wrong.
 
ChiefPilot said:
I think the idea is that the PMag wasn't solely to blame for the issue and was subjected to an environment outside it's design parameters. Frankly, I'm skeptical that such a failure could cause the timing issue and think maybe switchology might have been involved otherwise it's not clear how a powered-and-ungrounded PMag could revert it's timing.

And I could be completely wrong - or I could be completely right. Because that question exists, placing all the blame on the PMag is specious - and I think that is what Bill is getting at. I'd add only that he's not wrong.
Click to expand...

Thanks Brad. You are correct, this is a mix of faults. The OP is a good guy and when we spoke, he was unaware of the Emag SB. He is not happy but is not blaming Emag either. He is much more "collected" than I would be, if I were in the same situation!

The picture Dan posted is about two or three months old and is another reason you should check all your vendors for service bulletins!
 
Actually it is second

Walt said:
And lets also think about:


If the engine starts runnning rough, you have a lot on your plate, doing a 'MAG' check probably isn't the first thing that is going thru the pilots mind, so don't blame him.
Click to expand...

I'm not grading/insulting/judging etc anyone, but I think this is a dangerous comment. It lowers the level of performance expectation. To say that a pilot should not be thinking of a mag check in this situation is not accurate. If I have a recip that starts running rough, the first thing I'm going to do is push the mixture forward, turn the boost pump on and switch tanks. The second thing I'm going to do is a mag check. I've been in this exact situation and turned off the offending pmag and flew home on the other. I'm not evaluating one pilot's performance. Not my job. I'm talking about every pilot. If you fly airplanes, you need to be able to think clearly under stress. If it is time critical, such as engine failure on take off, it needs to be automatic. That is why there are boldface items in some aircraft. In fact, there should be boldface items in all aircraft. Some things just need to be muscle memory. On the other hand, if you are at altitude and have time, you need to be disciplined and methodical while attempting to solve the problem. Maintain aircraft control, analyze the situation and take the appropriate action. We have all heard those words and it is our responsibility to execute them. To say some one is going to be overloaded or overstressed and not accomplish basic EP items is not OK. I know we live in a society of participation trophies but that doesn't work in aviation. You either make the grade, quit flying or die. Even though we have a lot of fun doing it, this is serious business with dire consequences when not executed correctly. Fly safe.
 
N941WR said:
With the shorting described by the OP, the system was being grounded, which puts it in setup mode. (Powered but grounded is setup mode.)
Click to expand...

Allow me to backtrack a little on this; my understanding of the OP is that his power line was the issue, meaning voltage spikes and/or high rate of off/on situation on the +ve line coming out of the Alternator.

This should not affect the p-lead to become grounded. So IMHO, his PMag could have been powered and unpowered at a high rate in a short period of time along with voltage spikes on the line (depending on the quality of his battery acting as a buffer) but the P-lead would not be grounded. So its more like (Powered & Unpowered with ungrounded P-lead)

If setup mode can't be entered with p-lead ungrounded, so my first guess would be that its not the Setup mode + MAP line that changed the timing but could have been circuit leak due to the spikes that changed the value of the timing at the EEPROM register. Would have been interesting to read the value stored after this incident. If its circuit isolation issue, the value could be random or the max HEX value that register can store.

If anyone comes forward with a timing issue for V40, depending on their luck of having similar alternator line failure or spikes then a preventive hardware solution is called for maybe by using a small circuit in series with the power line feeding the PMag to cut spikes and regulate/clean up the line.

Rob
 
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ChiefPilot said:
Frankly, I'm skeptical that such a failure could cause the timing issue and think maybe switchology might have been involved otherwise it's not clear how a powered-and-ungrounded PMag could revert it's timing.
Click to expand...



NROBB said:
Allow me to backtrack a little on this; my understanding of the OP is that his power line was the issue, meaning voltage spikes and/or high rate of off/on situation on the +ve line coming out of the Alternator.

This should not affect the p-lead to become grounded. So IMHO, his PMag could have been powered and unpowered at a high rate in a short period of time along with voltage spikes on the line (depending on the quality of his battery acting as a buffer) but the P-lead would not be grounded. So its more like (Powered & Unpowered with ungrounded P-lead)

If setup mode can't be entered with p-lead ungrounded, so my first guess would be that its not the Setup mode + MAP line that changed the timing but could have been circuit leak due to the spikes that changed the value of the timing at the EEPROM register. Would have been interesting to read the value stored for after this incident. If its circuit insolation issue, the value could be random or the max HEX value that register can store.

If anyone comes forward with a timing issue for V40, depending on their luck of having similar alternator line failure or spikes then a preventive hardware solution is called for maybe by using a small circuit in series with the power line feeding the PMag to cut spikes and regulate/clean up the line.

Rob
Click to expand...

I also can't reconcile the theory that the P-Mag was grounded or somehow forced into setup mode with the supporting statements. How can a failure of an external alternator control wire cause the P-Mag's P-Lead equivalent to become grounded?

We must also keep in mind that anytime the P-Mag is above 800-900 rpm and the internal alternator is working properly, the P-Mag is self powered. My understanding is that the P-Mag uses a simple diode isolation circuit between the two power sources and the internal alternator is designed to be the winner in a typical experimental airplane's power system. The only thing I can think of would be abnormal random voltage "spikes" hitting the P-Mag (not sags or no power) at a voltage "higher" than that of the internal alternator but this does not explain how the P-Mag could enter setup mode....

Bet there is more to this story and I am not sure that V40 is the pixie dust that prevents whatever the true failure mode ends up being.
 
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Emag

Yes Brian that's my take when the OP is at 7500 in cruise and Emag on own power what happens when you turn landing light on it causes a flux?
Bob
 
Flux as in expanding and contracting magnetic field around the power-carrying wire. Start arcing a contact and you're getting something like random Alternating Current so those fields could be changing rapidly. So yeah, flux, of one sort or another.

Now where did I put that flux capacitor?!?! *grin*
 
For the benefit of future readers and me:

Did the PMAG have the latest software (40) that *should* have precluded this issue?

Dual PMAGS in my future...
 
It is my understanding that Pmags always use ship's power until it loses it and then reverts to the internal alternator.
 
Jesse said:
It is my understanding that Pmags always use ship's power until it loses it and then reverts to the internal alternator.
Click to expand...

Not correct according to the pMag install manual:

"Series 114 ignitions will transition off of aircraft power (and onto internal power) as the internal power rises. Somewhere around 1200 to 1500 rpm P-model ignitions should be operating totally on internal power. At this point, internal power is the ignition?s primary power supply and the aircraft power is the backup. Transitions to and from the aircraft power supply are managed automatically by the ignition. There is no need for operator action of any kind. If you loose external power, your P-model ignition is capable of providing emergency power down to 900 rpm, and sometimes less."

Carl
 
Thanks to Whit and Dan, for flagging the separation issue

I am one of those "in the zone", and most likely would not have looked until condition inspection, which is still some months off. Hopefully now that it is flagged, no one else will have to find out "the hard way"

I know Doug flags notes/bulletins fron Van's, maybe that can broaden out, or a special area could be created, and hold info for a few months, getting input from forum.
 
I have an affected unit...

I got a call today and learned I have one of the P-mags in the "build window" of problem units...

Not happy, since the thing hasn't even been installed 2 months yet...

I've got a call into EmagAir to discuss my options, but it looks like it will be coming back out again!

:mad:
 
For those considering pmag. Realize it isn't maintained free like Slick magnetos can be before the required 500 hr service that traditional mags sometimes require. I certainly thought I could get more than 60hrs on my pmag without maintenance but not checking the service notes (AD) bit me in the backside.

From the e mag 114 manual:

Maintenance: Annual or 100 Hr. Inspection (whichever comes first):

1. Check E-MAG web site for most recent Service Notes (www.emagair.com page ?Service Notes?) and verify equipment is current with all updates.

2. Ignitions come with a (one-time trigger) thermal sticker that will trip (turn from light ash color to gray or gray/black) if case temperatures exceed 200 degrees (F). If tripped, review blast cooling and/or other ventilation issues that affect ignition cooling. Keep ignition temperatures below 200 degrees.

3. Ohm check plug wires (see ?Ohm Check? above), and examine spark plugs for signs of unusual wear or build-up. Gap plugs per instructions above. Replace auto style plugs with new ones after 100 to 125 hours. When reinstalling auto style plugs with auto plug adapters, review plug/adapter installation guidelines above.

4. Remove ignition and examine shaft and drive gear condition. Note: Ignition disassembly is not necessary (and if done may void your warranty). Look for excessive play (lateral and axial). Shaft rotation should be free, with no catching, flat spots, or grinding. The shaft on ?P? models (with internal alternator) will have a push-pull rippling effect as the shaft turns and the permanent magnets pass the rotor poles. This is normal and expected. If a P model ignition does not have this magnetic ripple, the unit requires additional (shop) service.

5. Replace older 1/16? cotter pins with larger 5/64? cotter pin. Inspect and secure the ends to prevent movement. The smaller pins have been in service for some time, but we?ve have occasional reports of pins coming loose and/or breaking.

6. Examine control plug and coil plug connections. Tighten to 4-5 inch pounds. Verify there are no stray wire strands. Verify all control wires use the Adel clamp strain relief.

7. Reinstall the ignition, and verify proper operation. Review Setting Ignition Timing instructions above. For P models, re-verify minimum operating speeds when running on internal power (see Minimum Operating Speed test above.)
 
Raymo said:
For the benefit of future readers and me:

Did the PMAG have the latest software (40) that *should* have precluded this issue?

Dual PMAGS in my future...
Click to expand...

Based on my conversation with the OP, his P-mag was purchased just prior to the release of the V40 Service Bulliten.

Jesse said:
It is my understanding that Pmags always use ship's power until it loses it and then reverts to the internal alternator.
Click to expand...

As the others have stated, the early versions 113 series and prior, ran on Ship's power and only switched to internal power when ship's power is lost. 114 P-mags switch to internal power as the engine speed comes up. At around 800 RPM the internal generator produces enough power to be self sustaining.
 
Aggie78 said:
I got a call today and learned I have one of the P-mags in the "build window" of problem units...

Not happy, since the thing hasn't even been installed 2 months yet...

I've got a call into EmagAir to discuss my options, but it looks like it will be coming back out again!

:mad:
Click to expand...
How is that PMAG does not send notifications to those owners with the effected S/N. They have all of our info, including e-mails and they know which S/N went to which customer.
 
Bavafa said:
How is that PMAG does not send notifications to those owners with the effected S/N. They have all of our info, including e-mails and they know which S/N went to which customer.
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They address that right on their site in the section for the case bolts and state that they have contacted those they have records for. They do not have records for all, for example when purchased through an engine builder or other middleman.
 
Who nees V40?

I spoke with Brad at Emag this evening. He is aware of this thread and said he has received a number of calls from concerned customers regarding the V40 upgrade.

Those who do not have V40 and have a key switch to control the grounding of the P-mags are highly unlikely to have a lost timing issue.

However, if you have toggle switches and for whatever reason leave one P-mag grounded during the starting sequence, you do run a good risk of loosing your timing mark.

It is still unknown why the OP lost his timing mark on a running engine. It is possible that the arcing described by the OP caused the P-mag to lose its timing mark but Emag is still looking into the reason. V40 may or may not have prevented the OP's issue. Once Emag understands the cause, they will fix it and they will issue a service bulletin.

The good thing for those of us running P-mags, as long as you understand this failure mode, you can test for it on the ground. Should it happen in the air, I would perform a mag check in the air, knowing I may get a nasty backfire, if I shut off the wrong ignition. (Sorry, the EICommander can tell you have a timing issue but it cannot tell you which P-mag is out of time and it needs two P-mags to run the comparison. It would not have helped the OP.)

If you are uncomfortable turning off one ignition in flight, throttle back, go to full rich, and find a place to land ASAP.
 
So I pulled my P-mag today...

With a little help from a buddy, and since I'm local to the folks who made it, I shot over there with it in my hot little hands to drop it off for the fix.

The fix ended up happening "right now" and being about 10 minutes of bench time to disassemble, then re-assemble the mag with the thread locker installed.

In my case, I had no noticeable issues when I pulled the mag, and during the tear down it was found that I'd had one properly put together in the first place-thread locker was installed in all 4 locations where it was needed.

Comfort factor-we put it on the test bench and took it for a spin after re-assembly and she worked like a champ, and I plan on re-hanging it back on the engine tomorrow.

Brad and the folks at his company were apologetic about the the entire affair and the inconvenience folks were being put through.

Stuff happens when humans are involved...this is just one of those instances highlighting that fact.
 
Pmag issue update

I talked to Brad at Emagair about the evaluation of my Pmag. This is what I learned.

The inspection of my Pmag did not reveal any damage or discrepancies.

My Pmag did not have the V40 update installed.

As stated on the Emag website V40 is not a mandatory update.

He said there is no reason to believe that the V40 update would have prevented my loss of timing issue anymore than the V37 that was installed at the time of the event.

Brad said they do not have enough definitive information at this point to know why this inflight timing event happened.
 
prevention?

Post #1:
gbusterguy said:
... We found the connector on the end of the power wire coming off of the alternator had broken after 10 years of vibration and had been arching between the wire and the alternator,...
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Post #49:
gbusterguy said:
I talked to Brad at Emagair about the evaluation of my Pmag... He said there is no reason to believe that the V40 update would have prevented my loss of timing issue anymore than the V37 that was installed at the time of the event. Brad said they do not have enough definitive information at this point to know why this inflight timing event happened.
Click to expand...

Hi Loel... do you have specifics on the broken connector and preventative measures to keep it from breaking?
 
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