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Dual P-MAG Reliability in 2017

P- Mag failures

I have a RV-8 with dual P-Mags. Since the engine IOX-370 came with them installed and first flew in April 2017. I wasn?t advised about the blast tubes being required until I started experiencing failures of the Lt Mag. The left Mag is positioned between the oil cooler and the oil filter thereby being more exposed to heat. After three attempts of sending the P-Mag back to factory for rework they sent a new one. I then took the Rt Mag moved it to the left and put the new Mag on the right. After about 40 hours the original Mag failed completely. It?s on its way back to factory as I post this message. When they are operating things are great. I am looking for advise and comments.

To me these mags shouldn?t be this temperamental or unreliable. I think the option of going to regular mags would be expensive since auto spark plugs have a smaller diameter and the cylinders would have to be modified to accept regular aviation plugs.

Open to help and comments!
 
I have a RV-8 with dual P-Mags. Since the engine IOX-370 came with them installed and first flew in April 2017. I wasn?t advised about the blast tubes being required until I started experiencing failures of the Lt Mag. The left Mag is positioned between the oil cooler and the oil filter thereby being more exposed to heat. After three attempts of sending the P-Mag back to factory for rework they sent a new one. I then took the Rt Mag moved it to the left and put the new Mag on the right. After about 40 hours the original Mag failed completely. It?s on its way back to factory as I post this message. When they are operating things are great. I am looking for advise and comments.

To me these mags shouldn?t be this temperamental or unreliable. I think the option of going to regular mags would be expensive since auto spark plugs have a smaller diameter and the cylinders would have to be modified to accept regular aviation plugs.

Open to help and comments!

Yep - blast tubes are required - as is installation and operation per the manufacurer?s instructions. Install the blast tubes, it only takes a few minutes and fly on. I would never consider going back to mags.

Two side comments:
- You should thank eMag for providing the replacement. The eMag has an internal tempurature sensor so when you send the unit back they can tell how hot it got. You must have really cook yours.
- Unless you have a very unusual setup, your engine has spark plug adapters installed so you can use auto plugs. If you really want to put mags on, then take out the adapters and buy a box of overpriced aviation plugs.

Carl
 
the manual is important

... I wasn’t advised about the blast tubes being required until I started experiencing failures of the Lt Mag. .... I am looking for advise and comments.

To me these mags shouldn’t be this temperamental or unreliable. ...

Open to help and comments!
Hi, You may want to check the documentation for other things - if you didn't know about the blast tubes, there may be some other critical things about the installation or operation of these devices that you have missed. Here's the section from the manual that discusses the blast tubes:

Blast Tube Cooling (mandatory):
E-MAGs are designed for a high-heat environment, but even so there are practical thermal limitations. Air blast (cooling) tubes are a common and inexpensive way to reduce the ignition operating temperatures. We consider them mandatory. Blast tubes should be directed at:
[Lycoming] The narrow (round) portion of the nose section, and not at the rectangular electronics case itself.

The manual is less than 30 pages, and available on the emagair.com website.
 
I have a RV-8 with dual P-Mags. Since the engine IOX-370 came with them installed and first flew in April 2017. I wasn?t advised about the blast tubes being required until I started experiencing failures of the Lt Mag.

Patrick, have the failures been convincingly tied to temperature, i.e. the temperature tell-tales clearly show the P-mag was heated beyond it's limits? Or is overheating an assumption based on lack of blast tubes?

If memory serves, the service limit is something like 200F, with internal components supposedly good for 230F or so.

BTW, let's remember that blast tubes do nothing after shutdown, when temperatures are highest.
 
To me these mags shouldn?t be this temperamental or unreliable. I think the option of going to regular mags would be expensive since auto spark plugs have a smaller diameter and the cylinders would have to be modified to accept regular aviation plugs.

As a data point to consider - I put dual 114 series P-Mags on my IO-360 for first flight of my RV in late 2012. I just sent both of them back to emagair after >900hrs during which they performed without error or problem - they have just worked the whole time. Both have blast tubes positioned right at the cooling fins.

I sent them in for a check up since after 5 years / 900+ hours it seems like a pretty reasonable thing to do.
 
Which ignition

I put dual 114 series P-Mags on my O-320, RV-9. First engine start was, without question, quick and smooth. The timing setup is so simple - even I could do it :eek:.

Robert
 
Are you saying all of your fails were on the Left side? And the Right Pmag failed when move to the left hole? I had multiple mechanical and electrical Pmag fails on my 0-360 A1A, all on the Right side.
IMO, there is a weakness in the design that only presents on certain engines that?s not understood yet. If you have more than one fail with a Pmag you just need to move on to another system. Most people have very good luck with Pmags, no bashing intended, but if you have had a fail your chances of having more is pretty high.
Tim Andres


I have a RV-8 with dual P-Mags. Since the engine IOX-370 came with them installed and first flew in April 2017. I wasn?t advised about the blast tubes being required until I started experiencing failures of the Lt Mag. The left Mag is positioned between the oil cooler and the oil filter thereby being more exposed to heat. After three attempts of sending the P-Mag back to factory for rework they sent a new one. I then took the Rt Mag moved it to the left and put the new Mag on the right. After about 40 hours the original Mag failed completely. It?s on its way back to factory as I post this message. When they are operating things are great. I am looking for advise and comments.

To me these mags shouldn?t be this temperamental or unreliable. I think the option of going to regular mags would be expensive since auto spark plugs have a smaller diameter and the cylinders would have to be modified to accept regular aviation plugs.

Open to help and comments!
 
I have a RV-8 with dual P-Mags. Since the engine IOX-370 came with them installed and first flew in April 2017. I wasn’t advised about the blast tubes being required until I started experiencing failures of the Lt Mag. The left Mag is positioned between the oil cooler and the oil filter thereby being more exposed to heat. After three attempts of sending the P-Mag back to factory for rework they sent a new one. I then took the Rt Mag moved it to the left and put the new Mag on the right. After about 40 hours the original Mag failed completely. It’s on its way back to factory as I post this message. When they are operating things are great. I am looking for advise and comments.

To me these mags shouldn’t be this temperamental or unreliable. I think the option of going to regular mags would be expensive since auto spark plugs have a smaller diameter and the cylinders would have to be modified to accept regular aviation plugs.

Open to help and comments!

I just returned from Seminole this afternoon. Had I seen this earlier, we could have gotten together.

What type of propeller do you have?

Not knowing what type of failures you were experiencing, it is difficult to offer advice.

I ask because a neighbor had a carbon fiber ground adjustable prop and his mags wouldn't even make 40 hours before they would fail. He switched to a Catto and the problem went away.
 
Just a data point of one.


Single Pmag 114 in use since 2009 on the left side, unmodified IO360A1B6 angle valve (Velocity w/ MT prop)

No failures, no glitches, no issues. Over 600 hours use.

It's probably time to send it back for the $135 "Flat Fee Check Up" .

From a performance standpoint, it's been excellent on the A curve.
 
PMAGs internal power quits at low RPM!!!

One thing that I have not read in the past 16 pages and that worries me the most is the fact that the internal generators in the PMAGs quit working below a certain RPM. Depending on the unit that you own, this may be between 800 and 1300.

My signature shows RV-4 PH-EIL, sadly crashed.

Here's the crash report:
https://aviation-safety.net/wikibase/wiki.php?id=187798
most interesting is this link in it:
https://www.bea.aero/uploads/tx_elydbrapports/BEA2016-0325.pdf

It is in French. To those who do not master it, or have figured out Google translate yet: Paragraph 2.6.5 describes the official conclusion why the engine of Laurent quit on final - His rpms dropped below 1100, where the internal generators on his units quit working and required external power to continue. That power apparently wasn't there at this flight, for whatever reason. And so his engine quit, sending him into the trees, killing him and severely injuring his passenger.

He had installed dual PMAGs 5 flying hours prior to the accident.

So.... unknowingly, we all lose the primary source of electrons in these PMAGs and have to resort to its backup at a phase of flight where it can hurt the most.

Our RV4 has dual PMAGs and I love the smoothness, power, easy starting and low fuel burn. However, this is one aspect of them that I really don't like..

And I've lost a friend to them.
 
Hans, I am sorry to hear about your friend.

That is an interesting report.

I have never spoken with anyone who's P-mags would not self power above ~800 RPM.

This is also one reason why the internal generators should be tested before each flight.

I had one generator fail in flight and did not know it until the next preflight. Even then, the ship's electrical system powered the ignition without even a stumble.

If your P-mags are not self powering above ~800 RPM's, then you need to have a discussion with Emag. They are designed to to provide power when the prop is turning slowly on final.
 
I am very sorry to hear about your friend. It still hurts but unfortunately, if you are in aviation long enough you will eventually loose a friend.

I don't know all the details of this case but, with any airplane safety of flight system, redundancy is critical. In my case I have the engine driven alternator, the airplane battery and the P-Mag(s) internal generators (triple redundant) for ignition power. I also know, and have on my emergency action checklist, never to go below1,000rpm(s) in flight if I even suspect an electrical failure to the ignition. I check the 1,000rpm number during every engine run-up portion of the pre-flight check. Without a similar installation/procedure then you really need to re-think the basic installation design. No matter what, things will fail so minimize the posibility and consequence(s) of ALL critical equipment failures.

Just my 2 cents.

:cool:
 
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Hans, I am sorry to hear about your friend.

That is an interesting report.

I have never spoken with anyone who's P-mags would not self power above ~800 RPM.

This is also one reason why the internal generators should be tested before each flight.

I had one generator fail in flight and did not know it until the next preflight. Even then, the ship's electrical system powered the ignition without even a stumble.

If your P-mags are not self powering above ~800 RPM's, then you need to have a discussion with Emag. They are designed to to provide power when the prop is turning slowly on final.
 
Thanks guys. In all fairness, he was not a close friend. Nevertheless, I received RV flying pics from him from all over the place, all the way up to Mali and some other places deep down in Africa. I guess he figured that if he could land an Air France 747 there, he might as well do the same with his RV. Sad that he met his Waterloo in his own back yard...

Anyway, back to the PMAGs. We too check ours before flight. They were wired with just CBs when we purchased the plane, and we've added switches so that we can cut battery power to check for proper operation. Ours cut off somewhere between 800 and 900 rpm.

As for flying - I tend to come in high and fast and use sir Isaac Newton as my main propulsion during final, ideally bleeding my speed off in the last few hundred yards. In my Jodel with a huge constant speed prop this is easy. As in my Fly Baby with tons of exposed rigging wires. More of a challenge in a fixed pitch -4.

I like to believe that I would be ok even if the engine would quit on me on final. Still, good to keep this aspect of the PMAGs in mind, and mention it in a PMAG reliability topic such as this...

Be safe!

Hans
 
Hans, next time you fly, do a couple of landings and note your RPM's on final. If you are like me you normally don't look at it but I typically find mine to be around 1,000. Now I was messing with my idle last month and with my lightweight prop had it set so low the engine would stop on final, even with the P-mags firing. My engine is now set to idle right at 600 RPM's when warm.

My style of flying is much like yours. I try to make my landing spot without touching the throttle after I close it on downwind.
 
"Lost Timing" events would certainly worry me.

You can do all the analysis you want but in the end, the system either works properly all the time or it doesn't which means it's either well designed and tested or it isn't.

Nigel's independent testing uncovered several things about the product that people may not have known before. Information is good.

We don't worry about lost timing events or programming changes which don't take hold with SDS because they never happen. Change the timing on CPI and it's instant and accurate to within 1 degree. Shut off the unit or lose power while the engine is turning and it re-initializes and verifies crank position before starting the spark train again when power is restored. Anything else is not acceptable in our view.


...And THIS sums up why I'm ordering the new CPI2 along with a Slick mag for my Thunderbolt 390.

Thanks to everyone for their transparency. I really do get alot of information from a forum like this.
 
You can do all the analysis you want but in the end, the system either works properly all the time or it doesn't which means it's either well designed and tested or it isn't.

With that, perhaps we should never trust or use a Lycoming engine and render it poor design since there has been a few failures on those engine.
 
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With that, perhaps we should never trust or use a Lycoming engine and render it poor design since there has been a few failures on those engine.

How do you stretch my comment to Lycoming engines? We're talking EIs here. Anything can fail, mechanical or electronic. My comment was about specific design aspects on one EI which affected operation for years.

In my occupation, I get to hear all the bad stuff/ failures about not only our products, but also competitor's products from people using them in the field.

Do you believe "lost timing" and starting kickback events are acceptable on EI systems?
 
Do you believe "lost timing" and starting kickback events are acceptable on EI systems?

Ross,

I am interested in your products for my RV10 and will be considering them when I get to that point but both of these issues have been resolved for some time with the P-Mags. Many of these reports of failures leave out critical information and in many cases turn out to be installation issues or failure to update to the latest hardware/firmware or just plain old operator error.

My biggest beef with the P-Mag is the aggressive advance curve. As I reported six years ago, it is too aggressive. http://www.vansairforce.com/community/showthread.php?t=108079&highlight=curve

I use the limited programmability of the P-Mag to keep the advance under control.
 
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Ross,

I am interested in your products for my RV10 and will be considering them when I get to that point but both of these issues have been resolved for some time with the P-Mags. Many of these reports of failures leave out critical information and in many cases turn out to be installation issues or failure to update to the latest hardware/firmware or just plain old operator error.

My biggest beef with the P-Mag is the aggressive advance curve. As I reported six years ago, it is too aggressive. http://www.vansairforce.com/community/showthread.php?t=108079&highlight=curve

I use the limited programmability of the P-Mag to keep the advance under control.

Except that the 6-cyl PMag is still pretty much vaporware.
 
How do you stretch my comment to Lycoming engines? We're talking EIs here. Anything can fail, mechanical or electronic. My comment was about specific design aspects on one EI which affected operation for years.

In my occupation, I get to hear all the bad stuff/ failures about not only our products, but also competitor's products from people using them in the field.

Do you believe "lost timing" and starting kickback events are acceptable on EI systems?

Ross,
I believe Brantel covered it really well.
Such comment from a well knowledgeable person such as yourself on the subject matter will sound like he is trying to misrepresent the situation especially if he is a competitor

PMAG has had its fair share of issues and no one will know if there are still some undiscovered issues, much like any other product. But their simplicity in installation and the self-powering makes it a tough competition for any EI. But that is not to say that this is the product for everyone.
 
I am sorry for the loss of your friend. Reading the report however suggests this was not a PMag issue. The mechanic who did the install had never done one before. He incorrectly wired the Pmags to a common power source and after installation all RPM indications were lost. In addition it appears extensive work was done on the alternator and that it was inop for the flight and flights before. He was flying on battery only with no RPM indications on PMags. Not a good combination especially when known before flying.
G
 
Ross,
I believe Brantel covered it really well.
Such comment from a well knowledgeable person such as yourself on the subject matter will sound like he is trying to misrepresent the situation especially if he is a competitor

PMAG has had its fair share of issues and no one will know if there are still some undiscovered issues, much like any other product. But their simplicity in installation and the self-powering makes it a tough competition for any EI. But that is not to say that this is the product for everyone.

I didn't dredge up this 2017 thread and nobody disputes that Pmags are about the easiest EI to install on Lycomings and that lots of folks like them. They are probably currently the top selling EI for 4 cyl. Experimental Lycomings on the planet. I'd also say that things change in 2 years. What might have been valid in 2017 may no longer be...

There are numerous choices of EIs these days and people can buy whichever one they like.
 
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