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P-Mag troubleshooting

tkatc

tkatc

Well Known Member
While flying yesterday I lost my tach signal to my AFS-2500 engine monitor. I felt a light shutter when it happened and noticed I had no tach reading. I assumed it was a loose wire from my right P-mag to the AFS module for tach input. I checked those connections today and couldn't find anything out of place so I buttoned up the cowl and started the engine. It started fine but I still didn't have a tach signal...

I did a "mag" check and discovered the engine would shut down while attempting to run on the right P-mag. It would not run via the right P-mag on ships power or on its own internal produced power. Since the tach is fed from the right P-mag...I think the connection is just fine between the Pmag and engine monitor but the Pmag is not sending out any signal...

I have a call into Emagair but they haven't gotten back to me. I have not installed this system so I am a but lost when it comes to troubleshooting.

I figure if the engine was running (via the left p-mag) then the gear in the right p-mag would be spinning enough to produce internal power in that mag and should run....no? Makes me think perhaps the gear has malfunctioned?

On the other hand....even if the gear was not even installed....would it not produce power via ships power? Maybe not because it wouldn't know the timing. I suppose I am leaning towards a bad gear but I am just troubleshooting without any real knowledge of how this thing works.

What do the experts think?
 
check ground wire

Check your ground wire. Make sure you have a great connection to the pmag and to the engine itself. Very important.
 
If it won't run on the right Pmag the first thing you should check is to see if the Pmag will power up in setup mode.

Place the Pmag in setup mode. You will need to get the install manual from Emagair for directions. This will allow you to validate that your Pmag is powering up and also allow you to see if the Pmag is timed correctly. I.E. Once in setup mode rotate the prop until it reaches TDC. You should have a green LED if timed, yellow or red if not.

If it's in setup mode without any LED indications and you have checked the power and ground wires then most likely it is inoperative and will need to be sent back.

In my experience Emagair support has been above and beyond what I have received from other vendors. They will take good care of you.
 
It is probably a power/wiring issue. However, some of the early gears Emag sold were not heat treated properly. If you remove the Pmag make sure to tale a close look at the gear. One of our EICommander customers found his gear going bad and used the EIC to find it. Note, the gear did not go bad all of a sudden , as you described , but over a few flights.
 
Brad called me back and we had a brief conversation. From the facts that I gave him, he wants the unit back. He told me that while spinning, you could rip the 6 wire connector right out of the unit and it should still run. He thinks it is a problem at the "board" level.

Guess I get to learn a little more about my airplane...:eek:
 
tkatc said:
Brad called me back and we had a brief conversation. From the facts that I gave him, he wants the unit back. He told me that while spinning, you could rip the 6 wire connector right out of the unit and it should still run. He thinks it is a problem at the "board" level.

Guess I get to learn a little more about my airplane...:eek:
Click to expand...

Please let us know what the issue was when you find out. There are many of us here that run a p-mag. I have been running one for 120 hours now with no problems.
 
Which...

..... P-mag version do you have?

If you have the 113 or 114, is the required SB performed?
It came out in 2008:
http://www.emagair.com/E-MAG Service Bulletin 3_REV.pdf

I second the post above regarding Brad and E Magair: their customer-care and service is among the very best I have ever experienced!

If the problem is with the "board", they'll take care of it! :)

Good luck and let us know how it turnis out.
 
I removed the suspect P-mag today (113 series WITH the 2008 SB complete), it was relatively easy considering the tight workspace and multitude of cables and wires. I had it off in less than 20 minutes. I was skeptical that is was an actual unit failure and not wiring related. Seems like the only trouble I ever have with this plane is wiring issues cause by vibrations.

I was relieved to discover the gear was "crunchy" when rotated by hand. Reading threads here I suspected some sort of internal magnet failure. I quick call to Brad and he also speculated the same thing. The unit is on its way to E-Mag and should arrive Friday or Saturday at the latest. I expect to hear something by Wed if not sooner. I will post the results.
 
Got a call from Brad early this morning. He recieved my fauly P-mag and had it apart. One of the magnets had come loose as suspected. It disintegrated into a fine dust and the binding was a result of that dust. He said he would remedy all that at no cost to me besides shipping. EXCELLENT! BUT...the dust made its way into the "board" area and coated the board with a fine mist of magnetic dust. The board had to be replaced and it cost me $425.

Can't say I am happy but can't say I'm unhappy either. I think this is as fair as can be expected. Parts fail, period. Even traditional mags fail so I am not turned off with the P-mag set up. I rather enjoy the dual P-Mags when I am looking at my GPH burn rate.

Brad mentioned that my heat indicator sticker had turned gray indicated temps near of above 200F. He said the sticker would turn black if it was extreme temps but cautioned my set-up. I asked if he thought heat had anything to do with my failure and he said no but it was just something to keep an eye on. The 2 things that cause failures on this component, as all others, are heat and vibration. So try to eliminate as much of that as possible. (Get that prop balanced!!)

I will say that the service from Emagair was QUICK and very responsive. They got the P-mag Friday or Saturday and it was sent out the following MONDAY! One day turnaround. I admire that even if I don't like paying for failures.
 
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Oh...one more question...can I re-use the gasket to re-install the repaired P-mag? And I also noticed some sort of silicone sealer between the flange of the p-mag and the gasket. Anything I should know about that? I don't think the instructions address that.
 
tkatc said:
The 2 things that cause failures on this component, as all others, are heat and vibration. So try to eliminate as much of that as possible. (Get that prop balanced!!)
Click to expand...

Exacty right and this is why I'll never own a PMag or any ignition with electronics bolted directly to the engine.
 
tkatc said:
Got a call from Brad early this morning. He recieved my fauly P-mag and had it apart. One of the magnets had come loose as suspected. It disintegrated into a fine dust and the binding was a result of that dust. He said he would remedy all that at no cost to me besides shipping. EXCELLENT! BUT...the dust made its way into the "board" area and coated the board with a fine mist of magnetic dust. The board had to be replaced and it cost me $425.

Can't say I am happy but can't say I'm unhappy either. I think this is as fair as can be expected. Parts fail, period. Even traditional mags fail so I am not turned off with the P-mag set up. I rather enjoy the dual P-Mags when I am looking at my GPH burn rate.

Brad mentioned that my heat indicator sticker had turned gray indicated temps near of above 200F. He said the sticker would turn black if it was extreme temps but cautioned my set-up. I asked if he thought heat had anything to do with my failure and he said no but it was just something to keep an eye on. The 2 things that cause failures on this component, as all others, are heat and vibration. So try to eliminate as much of that as possible. (Get that prop balanced!!)

I will say that the service from Emagair was QUICK and very responsive. They got the P-mag Friday or Saturday and it was sent out the following MONDAY! One day turnaround. I admire that even if I don't like paying for failures.
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Wow, major bummer. I don't agree with the charge at all. How many hrs did it have in it? Guys, can we "reset the counter" now?
 
rocketbob said:
Exacty right and this is why I'll never own a PMag or any ignition with electronics bolted directly to the engine.
Click to expand...

Criticism of the PMag is hereby forbidden. ;-) I just bought one and made the first flight with it this morning.

Temperatures are my big concern with the unit. I wish there was a better solution than blast tubes. I don't see them helping much in what I consider the worst case scenario (post shut-down on a hot ramp).
 
monitor the temperatures with a thermocouple...

I installed a couple of thermocouples for general info and troubleshooting... after moving them around a bit to explore I ended up leaving one at the PMag and one near the exit, generally at the hottest point that I encountered.

I have them landed on my Skyview and the temps are displayed along with other engine data.

Typical in-flight temps at the PMag are around 110 or less... the temp at the exit (near the oil cooler exhaust and engine exhaust pipes) usually runs around 140... on the ground, on a hot day, after flying, both temps run up about 30 degrees.

Here is the thread with some photos of the thermocouples installed
http://www.vansairforce.com/community/showthread.php?t=84256
 
The p-mag had less than 400 hours total time. It has even LESS time since the mandatory service bulletin to replace/resecure the magnets. The same magnets that caused this failure. :(
 
scard said:
Wow, major bummer. I don't agree with the charge at all. How many hrs did it have in it? Guys, can we "reset the counter" now?
Click to expand...

I don't care for the charge either but one failure a trend does not make...

Also, didn't Tony buy this plane flying with the P-mag installed? If so, how good is the history on this unit?
 
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Brantel said:
I don't care for the charge either but one failure a trend does not make...

Also, didn't Tony buy this plane flying with the P-mag installed? If so, how good is the history on this unit?
Click to expand...

I agree, but one failure can make for a very bad day. And, I personally can add THREE to Tony's one.
 
I received the repaired P-mag on Thursday. (Would have been here by Wed with USPS but most vendors like UPS for some reason). Not a bad turn around for a repair. I installed the unit today. Pretty easy really. Took me awhile since I haven't done this before. Longest part was figuring out when my engine is at TDC according to the markings on the flywheel. I could've done it the old fashioned way by removing the plug, etc but then I would have to remove the plenum and....blah blah blah. Anyway, got it installed. Timed both p-mags together. LEDs were both green but the right one flickered with just the slightest hint of orange. A quick call to Brad and he set me straight and explained the nuances of gear lash and a few other things. Bottom line, I was timed perfectly and was good to go. While I'm still not happy about the $450 charge, the service from Emagair is top notch!

Test ran the engine, ran great, tested the internal power function, ran great. The repaired p-mag ran better than the one that hasn't failed. I was able to idle down to 830 or so RPMs and it still kept making its own power. The non-repaired p-mag shut down as I reduced below 940 or so. I was satisfied with the performance and there were no leaks on the repaired p-mag, and all I used to seal it was the new gasket supplied by E-mag.

Buttoned the plane up and went for a 30 min flight to get the cheapest gas around. It is 97 and humid here today and I'm happy to report the engine ran well. CHTs and EGTs were below 400 and 1400 respectively and oil temp stayed between 200-210.

I'm happy she's back in action! BTW, the RPM gauge works again! ;)
 
tkatc said:
...the gear was "crunchy" when rotated by hand. Reading threads here I suspected some sort of internal magnet failure. I quick call to Brad and he also speculated the same thing. The unit is on its way to E-Mag and should arrive Friday or Saturday at the latest. I expect to hear something by Wed if not sooner. I will post the results.
Click to expand...

Well, the same thing has now happened to me. This last weekend I got no tach signal, elevated EGTs, failed mag check on my left side, and upon removal of the p-mag, a crunchy gear when rotated. Sending the unit in now, but Brad says its likely a broken magnet. Hope I dont have to pay for a board replacement as well and that they have or are working on some way to lessen the liklihood of this failure mode.

erich
 
erich weaver said:
Well, the same thing has now happened to me. This last weekend I got no tach signal, elevated EGTs, failed mag check on my left side, and upon removal of the p-mag, a crunchy gear when rotated. Sending the unit in now, but Brad says its likely a broken magnet. Hope I dont have to pay for a board replacement as well and that they have or are working on some way to lessen the liklihood of this failure mode.

erich
Click to expand...
How about some details? Hours in service, one or two P-mags, cooling tube installed, engine and prop, etc.?
 
How long did you fly after the failure? I estimate less than 30 minutes for mine. Let's hope the board is not coated with the magnetic dust but since it stopped reporting the tach signal, I suspect it is. Turnaround is swift but the $450 bill will take longer to resolve. :eek:
 
Is there some common thread to these failures? Version ? Model ? Etc ? It's not giving me a warm or fuzzy feeling.
 
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N941WR said:
How about some details? Hours in service, one or two P-mags, cooling tube installed, engine and prop, etc.?
Click to expand...

Dual p-mags, total time is 275 hrs, but p-mags were changed out sometime in the first 50 hrs or so and replaced with what they gave me - I know they werent brand new but no idea how many hours were on the replacements. They are model 113 bodies with 114 boards I believe. Cooling tubes installed, IO-360B1B, Whirlwind prop with dynamic balance. I believe Brad has previously stated that heat is unlikely to be related to magnet disintegration.

My tach signal went out temporarily initially, and I chocked it up to a bad connection. My next flight it was on initially and then gone for good. Flew for maybe a half hour with no tach and apparently only one pmag. I'll report back with the $ damage if any. Holding out hope for now.

erich
 
What is really important for us to know in these cases is the DATE of manufacture - not the hours on the engine - someone might have a problem at fifty hours - but it sat in their garage or workshop for four years while they were building. Brad has made incremental and positive improvements over the years, and the latest units are getting pretty reliable. What we need to look out for are late-model failures that indicate problems not-yet-solved.

Paul
 
Paul, makes sense but MY units were sent in for the mandatory SB issued by EmagAir concerning magnet adhesion. Perhaps there is a difference between models that were made with the improved methods vs the eiarlier ones that needed the SB performed on them but I like to think the SB SOLVED the issue and there would be NO difference.
 
Will have to check the log book to see when my pmags were changed out by Brad, but like I said, they have model 114 boards in them, so. not all that old. I'm not aware of any upgrades since the 114 was put out there, but correct me if I'm wrong.

Erich
 
Talked to Brad this morning. Magnet was shattered for unknown reasons - it was not due to the lack of integrity of the attachment method though according to Brad. If all that happens is the magnet shattering, the unit should lose self-power capability and still work fine through ships power, but apparently there was also evidence of over-heat damage to the chip that controls this, so that was out as well. It is not clear then if this was all one related failure event or two separate events. I (lamely) wasnt doing regular checks of the units self-powering capability during run-up, but if I had, that information could be correlated with my loss of tach signal to determine if this was a single failure or two separate ones, as the loss of tach signal would mark the point where the unit wasnt working at all.

The likely heat damage is a bit troubling, as I have blast tubes pointed at the neck of the unit, I havent had any indications of over-voltage conditions or other electrical system problems, and my CHTs and oil temps are kept within the acceptable range. Dont like the idea that all engine-related temperatures are fine EXCEPT for the ignition system.

On the positive side, customer service still excellent. They are turning them around in one day. Now to considering all my options...

erich
 
tkatc said:
So what was the cost of repair?
Click to expand...

Received an invoice for shipping that indictes a separate bill for repair will be coming. Bad on both them and me that there was no prior agreement or even discussion concerning cost; essentially, we had no real contract inlace. All my previous experience with them resulted in charges only for shipping, so that was my expectation, although I guess you can't get free repairs/replacements forever.

I will report back on the $ amount.
Erich
 
Got the units back today (I had asked for one day turn around and overnight shipping). Looks like I was charged a premium for the expedited "shipping and handling" at $101.25, but no additional charges for the repair and inspection, so happy about that. Still concerned about the failure however.

Erich
 
So it sounds as though they REPAIRED the damaged chip vs replacing it as they did in my case. If that is the case then I am glad your failure was repairable but still miffed mine wasn't.

I guess time will tell if this type of failure will become common. I will be watching with great interest since I am flying with AND planned to fit the RV-8 I'm building with dual PMAGS.
 
Another one!

Lost mine today. Enroute home and 75 miles out I lost the tach signal, did an inflight test and when I turned the mag off lost all power. Several minutes later the tach comes back on so I tried the PMAG and it comes back on (I had turned it off) and it ran fine all the way home.
Safely home, I tried to put it in setup mode and the LED is rapidly flashing yellow. Went to lunch, came back and it goes right into setup and I get the red/ green lights and it is properly timed.
Sticker is light grey, this is on a Cozy so the Pmag is on the cool side.
Installed 13 months and 110 hrs ago.
Not happy, if this had happened 2 hours earlier it would have been over northern Nevada. It's a long way between airports and no radar or radio coverage up there.
Tim
 
Tim, call Brad. He is very responsive and will walk you through the things to check. You may not be happy in the end but better than hours of troubleshooting only to end in in the same place. At only 110 hours I would expect him to step up and repair under warranty. Good luck.
 
I also had a P-Mag failure 2 weeks ago 250 miles from home, which I will write up in a separate thread in a couple of days. The blinking yellow LED, according to a phone conversation with Brad at Emagair, indicates that the (axial) shaft position is out of tolerance. If it gets bad enough, the unit will not even boot when powered up (which is what happened to me), and it sounds like also what happened to you.

Unfortunately, this is an undocumented feature, not mentioned in the manual anywhere. Why it's not, I will never understand. Should this really be a secret? Where you're relying on some guy on the internet to tell you how a product works second hand?
 
It is documented

Noah said:
Unfortunately, this is an undocumented feature, not mentioned in the manual anywhere. Why it's not, I will never understand. Should this really be a secret? Where you're relying on some guy on the internet to tell you how a product works second hand?
Click to expand...

It is documented, but only on their web site in the trouble shooting section which you must download to read. I found it after a little web drilling.
Ill call Brad Monday, I'm hoping for some of his reported great CS, I'm not much interested in paying $450 to have it repaired. It certainly ought to last more than 100 hrs. and I'm pretty sure he will agree.
I just had it off during condition inspection maybe 10 hours ago, it spun just fine and has performed great until today.
Tim
 
Replace Circuit board yourself

While away from home I had a P-Mag issue, I would get a backfire on mag check. Turns out it I was loosing the timing on the right mag (dual P-Mag 114 type). It re-timed fine and a ground check was good but as a precaution I called Emag Air. Brad wanted to see the mag so I sent it off to him. He could not find anything wrong but felt it might be the circuit board, no temp issues with mine. He gave me the option of him installing the board for $425 or he would send the new board and I could install if needed. He did not charge me up front for this, the idea was if my mag ran fine after I received them (even thought he found nothing wrong with them) I could return the board, if I used the board then it was only $250 charge for he board.

My mag continued the problem, It would time and was good for one flight then it would loose the timing and fail the next mag check prior to flight. I ended up changing the circuit board, this is a very simple process, and I have not had any issues with the mag since. I was at Sun n Fun and returned the defective board to Brad. Once Brad realized I only had 60 hours on the mag even thought I bought it in 2009 he did not charge me for the new circuit board.

I can't say enough about the great customer service from Brad. I think some prorated type of bill would have been fair price but getting the new board for free seemed fair as well with the low time on the mag.

I run dual P-Mags and love them and feel as safe with them as I would with traditional mags. You only need one and a dual failure is highly unlikely.

I have not heard back from Brad but we suspected a bad connection on the circuit board that would be fine when cool but after a flight with normal heating and vibration would cause the timing to come off. It would still fire the plugs but not at the programed time. Of course inflight you would not know it shifted running dual mags.

Cheers
 
Easy contact

Noah said:
The blinking yellow LED, according to a phone conversation with Brad at Emagair, indicates that the (axial) shaft position is out of tolerance. If it gets bad enough, the unit will not even boot when powered up (which is what happened to me), and it sounds like also what happened to you.
Click to expand...


Ive been in touch with Brad, he was quite easy to contact even on the weekend and they will take care of it. It is an alignment issue, and it sounds like this has been since resolved in current production.
Tim
 
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