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E-mags - love them hate them

Danceswithcumulus

I'm New Here
Its been a year since I installed dual emags, and I thought I would share my observations. First, they have performed flawlessly to date. When I switch between mags during the runup I see zero rpm fluctuation between L,R, and Both. That's pretty dang impressive. The auto plugs work great and look great after 50 hours of use.

Now the bad part.
I am doing my first annual inspection on them this week and I was shocked to read the manuals instructs me to: "Remove ignition and examine shaft and drive gear condition." I am then told to "Look for excessive play (lateral and axial). Shaft rotation should be free, with no catching, flat spots, or grinding."

Excuse me - why is this necessary? Mechanics aren't required to remove and inspect magnetos annually, so why should you have to remove E-mags to inspect them? Shouldn't such issues have been identified and resolved by intense trial evaluation on a test aircraft before selling them to the public? I have time to vent because I didn't see this removal requirement coming and didn't buy two new mag gaskets, so now I have to wait a week for them to come by mail.

More fun came. To remove an Emag you must remove the green wire harness attachment plug. This attachment is held in place with two small flathead screws that are deeply recessed in the plastic housing. A very small screwdriver is needed. Yesterday I tried several small screwdrivers and to my horror the face of one of those screws is now stripped flat and it wont loosen. That means to remove the E-mag I had to remove the three wires that feed it. Here is where the fun really began. The wires are held in place with guillotine clamps and the screws that tighten them are on the backside of the green attachment module, between the emag and the engine. You cant get a screwdriver in there with the emag bolted in place. Had they put the screws on the other side, they could be accessed easily. So that means you have to remove the emag and and hold it with one hand while loosening the wire clamps with the other, all in a cramped engine compartment. I later received complaints about the creative yet unwanted profanity coming from my hangar.

While on the topic of that green attachment, using guillotine wire receptacles to hold wires in a high vibration environment seems like a bad idea to me - its asking for wires to fail. Dont tighten them enough and they wiggle out over time. Overtighten and it cuts strands and then the rest break over time. I have had both instances happen in 12 months and yes I have the wires secured with an adel clamp. I wish the designers had employed a robust permanent wire harness so that the connections to power, ground, and P-lead can be made well away from the emag. That harness should be several feet long so that it can be secured to the engine mount and the connector can be of your choosing and location of your choosing. It would make removal and reinstallation of the E-mag much simpler.

Curious if others have had similar experiences to mine and have found work arounds. Anyone else had a screw face strip in the green module? How did you get it out?
 
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Search for PMAG

Then read the post by Walt.
U have Pmags. They require periodic inspection as detailed in Walts post and the manual.
Are ya going to buy 2 gaskets, or more?
 
Its been a year since I installed dual emags, and I thought I would share my observations. First, they have performed flawlessly to date. When I switch between mags during the runup I see zero rpm fluctuation between L,R, and Both. That's pretty dang impressive. The auto plugs work great and look great after 50 hours of use.

Now the bad part.
I am doing my first annual inspection on them this week and I was shocked to read the manuals instructs me to: "Remove ignition and examine shaft and drive gear condition." I am then told to "Look for excessive play (lateral and axial). Shaft rotation should be free, with no catching, flat spots, or grinding."

Excuse me - why is this necessary? Mechanics aren't required to remove and inspect magnetos annually, so why should you have to remove E-mags to inspect them? Shouldn't such issues have been identified and resolved by intense trial evaluation on a test aircraft before selling them to the public? I have time to vent because I didn't see this removal requirement coming and didn't buy two new mag gaskets, so now I have to wait a week for them to come by mail.

More fun came. To remove an Emag you must remove the green wire harness attachment plug. This attachment is held in place with two small flathead screws that are deeply recessed in the plastic housing. A very small screwdriver is needed. Yesterday I tried several small screwdrivers and to my horror the face of one of those screws is now stripped flat and it wont loosen. That means to remove the E-mag I had to remove the three wires that feed it. Here is where the fun really began. The wires are held in place with guillotine clamps and the screws that tighten them are on the backside of the green attachment module, between the emag and the engine. You cant get a screwdriver in there with the emag bolted in place. Had they put the screws on the other side, they could be accessed easily. So that means you have to remove the emag and and hold it with one hand while loosening the wire clamps with the other, all in a cramped engine compartment. I later received complaints about the creative yet unwanted profanity coming from my hangar.

While on the topic of that green attachment, using guillotine wire receptacles to hold wires in a high vibration environment seems like a bad idea to me - its asking for wires to fail. Dont tighten them enough and they wiggle out over time. Overtighten and it cuts strands and then the rest break over time. I have had both instances happen in 12 months and yes I have the wires secured with an adel clamp. I wish the designers had employed a robust permanent wire harness so that the connections to power, ground, and P-lead can be made well away from the emag. That harness should be several feet long so that it can be secured to the engine mount and the connector can be of your choosing and location of your choosing. It would make removal and reinstallation of the E-mag much simpler.

Curious if others have had similar experiences to mine and have found work arounds. Anyone else had a screw face strip in the green module? How did you get it out?
I’m not a fan of the yearly inspection either, speaking as a “victim” of excessive shaft play that almost left me stranded, if it wasn’t for the fact that Brad was kind enough to talk me through a temp fix on a Sunday afternoon, so I could get home. Have to love the company support.

Having said that, I am a true fan of my dual Pmags, and will never look back at Slicks.
There is a lot that can go wrong inside of a Slick as well, so I think it’s a wash from the yearly inspection, not to mention a **** of a lot easier to reinstall & time and not have to worry about that silly locking pin.

As to the inspection itself. Here’s my 2 cents:
I don’t use anything in the gasket, I keep it dry except for a very thin film of oil. I find that I don’t have to replace the gaskets and if/when I do, no issue with scraping.

As for the screws,
When I check these for security, I use a very long (6”?) small tip screwdriver to access the recesses without damaging the screws. And in my installation, using that long screwdriver allows me to attack the head straight-on with pressure.

I can leave everything connected, and still pull the mag out far enough to check the shaft, gear, and cotter key. A little tight on the RH side because of my F/W mounted oil cooler but still doable. I do have to disconnect my ground wire.

YMMV
 
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Have had play in the shaft a couple of times. Probably some harmonic issue with my engine. Don’t routinely change the gasket, and never had any leaks there. I don’t have to remove any wires to perform the inspection. Just pull it away from the case a little. Move the shaft per the instructions and hopefully put it back in place. The hardest part is making sure not to drop any bolts, washers or the retaining clip in the back case.

Buy the star washers in bulk though….
 
Couple of comments - I agree that it's annoying to have to inspect the pmags. I hope they find a more permanent fix and offer an upgrade.

If you are not getting any RPM drop I'd be concerned that you are not actually turning off the pmag.

For the wires, I'd recommend installing ferrules with a very good ferrule crimper. I just bought some recently and will probably add them during my next inspection. I hope the emagair team starts recommending these as they are apparently a very good idea - no experience yet, but just seems like good physics.

Getting that little screw out - ouch - I'd get a very small "electronics" screwdriver and get medieval with it. And of course call emagair for a replacement.
 
Ref the guillotine connectors... Yup, I love to hate 'em, too, but they work, plain and simple.

Don't like 'em still? Crimp standard D-sub sockets on your wires, then affix the D-sub socket into the guillotine. The socket will dent & deform under screw pressure. Ain't no way in heck it's coming out.

Really don't like 'em still? Do the D-sub socket routine noted above, then move up the wiring harness to a logical disconnect point (maybe 6" to 12") and install AMP CPC-style connector with gold contacts (Stein sells them if you want 'easy', otherwise find them on Mouser, Digikey etc). Very reliable connectors for not much money. Or go with the Deutsch automotive-style connectors mentioned in other similar discussions in these forums. Just make a quick-disconnect slightly up-stream so you never have to remove that green connector.

As for the annual inspection, yes, it's a pain. Just wait until you have an impulse coupler on your Slick mag turn into a metal-making grenade. Then you'll have graduated from simple "pain" to "excruciating pain". Thanks, I'll take the relatively painless annual inspection.
 
Pmag rpm drop

I have a pmag/slick setup in both airplanes. I get a relatively normal drop when running on the pmag only during run up. When I bought one of the planes there was no drop, and the owner was telling me how efficient the pmag was. I got home, double checked the wiring and realized he had a broken wire....
 
As for the annual inspection, yes, it's a pain. Just wait until you have an impulse coupler on your Slick mag turn into a metal-making grenade. Then you'll have graduated from simple "pain" to "excruciating pain". Thanks, I'll take the relatively painless annual inspection.

YEP YEP YEP! I speak from experience on this one. I'll take a Pmag inspection any day over having those garbage impulse couplers in my engine!

Just a side note everyone, it's an annual inspection OR a 100 hour inspection whichever is first.

I just did mine last week. I have enough wire I don't have to remove the plug.
 
I thought for personal use, just annual, 100 hrs for rental and other revenue generating planes.
 
I thought for personal use, just annual, 100 hrs for rental and other revenue generating planes.

You are thinking of the general inspections of the entire aircraft. I was pointing out what Emag recommends for their ignitions in their manual. They want the inspection (which is 7 steps in the manual) to be done at annual or 100 hrs whichever is first.
 
Choices

Agree with all the comments and solutions. However, SDS crank triggered ignition avoids all these issues. Just sayin, let the
The flames begin 😊
 
Took my P-Mags out and checked them on the bench the first 3 CIs. Those little screws were a pain to get at let alone loosen & retighten. This year I didn't disconnect any wires and just pulled the P-Mags out enough to check the gear & shaft & check the torque on the little screws in a more accessible location. Only half a pain. Replaced the gaskets - I've got a 5 yr supply.
P-Mag.jpg
P-Mags have been flawless - 235 tach hr, 297 hobbs
 
Is the p-mag gasket the same as the Slick magneto one?

Not exactly. The Pmag gasket seems to have a slightly smaller OD. The Slick gasket stick out about 1/16" around the circumference. I put a Slick gasket on because that is what I had. I made real dang sure though that the hold down clamps weren't resting on the gasket, even used a borescope to verify. Don't know if the clamps will be the same for every installation though so be careful out there.
 
Agree with all the comments and solutions. However, SDS crank triggered ignition avoids all these issues. Just sayin, let the
The flames begin 😊
True, that would solve half the problem. The pmags also have a generator which is powered by mag drive gear. That's probably one of the main reasons they are popular - no need for resilient power to the pmag to keep the engine running.
 
No need to buy special screw drivers for those little screws. Take a piece of Stainless Steel hinge pin about a foot long. Grind a screwdriver tip on one end and bend 90 deg on the other end. Makes removal and replacing the connectors fairly simple.
 
True, that would solve half the problem. The pmags also have a generator which is powered by mag drive gear. That's probably one of the main reasons they are popular - no need for resilient power to the pmag to keep the engine running.

Of course there is that pesky single ground wire...
 
You know why P-mags continue to be popular? Because Brad and Co very obviously bust their butts to take care of their customers. I'm not a P-mag fan at the technical level, but I really admire how they run their business.
 
You know why P-mags continue to be popular? Because Brad and Co very obviously bust their butts to take care of their customers. I'm not a P-mag fan at the technical level, but I really admire how they run their business.

Much this. Brad has taken what I'd call an inordinately large amount of time with me on the phone to discuss how the mags work in my airplane and has offered suggestions and solutions to my questions - not just the hows, but the whys. The education has been invaluable.
 
No need to buy special screw drivers for those little screws. Take a piece of Stainless Steel hinge pin about a foot long. Grind a screwdriver tip on one end and bend 90 deg on the other end. Makes removal and replacing the connectors fairly simple.

Or just buy a cheap small screwdriver and grind the sides so it fits. I labeled the one I made as Pmag Driver. ;)
 
I recently a minor issue with what I thought was my RH P-Mag. Brad and Trenton spent 2-3 hours on the phone with talking through various troubleshooting ideas. They get an A+ for customer service. The issue turned out to be bad NGK BR8ES plugs, but Brad was will to do anything possible to help me.
 
I recently a minor issue with what I thought was my RH P-Mag. Brad and Trenton spent 2-3 hours on the phone with talking through various troubleshooting ideas. They get an A+ for customer service. The issue turned out to be bad NGK BR8ES plugs, but Brad was will to do anything possible to help me.
Exactly what was the issue that pointed to the plugs?
 
You know why P-mags continue to be popular? Because Brad and Co very obviously bust their butts to take care of their customers. I'm not a P-mag fan at the technical level, but I really admire how they run their business.

I have to offer a Plus One to this comment. There are a bunch of really great vendors in the Experimental community, but these guys take it to a new level.
 
I too am running dual Pmags with 0ver 200 hrs flawless operation up until today. while inspecting the left P Mag control wires i found 3 out of 5 wires with broken strands, Does anyone perhaps have a photo of the D-SUB sockets mentioned in post from Canadian_joy? I also thought I might solder tin the ends of the wires prior to clamping with the gillotine????
 
I too am running dual Pmags with 0ver 200 hrs flawless operation up until today. while inspecting the left P Mag control wires i found 3 out of 5 wires with broken strands, Does anyone perhaps have a photo of the D-SUB sockets mentioned in post from Canadian_joy? I also thought I might solder tin the ends of the wires prior to clamping with the gillotine????
I suggest you explore the use of small ferrules on the end of the wires going into your green plug. This.was suggested to me a while back because I was having issue. I purchased a small ferrule kit through Amazon and installed them on the wires going into the green plug. Made a much better and more robust setup.
 
I suggest you explore the use of small ferrules on the end of the wires going into your green plug. This.was suggested to me a while back because I was having issue. I purchased a small ferrule kit through Amazon and installed them on the wires going into the green plug. Made a much better and more robust setup.
Small ferrules, i'm in search of now...thanks for the tip
 
I too am running dual Pmags with 0ver 200 hrs flawless operation up until today. while inspecting the left P Mag control wires i found 3 out of 5 wires with broken strands, Does anyone perhaps have a photo of the D-SUB sockets mentioned in post from Canadian_joy? I also thought I might solder tin the ends of the wires prior to clamping with the gillotine????

"Small ferules" = d-sub pins. Lots of folks have the appropriate crimper.

Now, does your installation incorporate an adel clamp to fixate the wiring harness to the p-mag body, before it goes to the green connector? Folks who hang wires from connectors, flopping in the breeze, really kinda deserve broken wires.
 
".... I wish the designers had employed a robust permanent wire harness so that the connections to power, ground, and P-lead can be made well away from the emag. That harness should be several feet long so that it can be secured to the engine mount and the connector can be of your choosing and location of your choosing. It would make removal and reinstallation of the E-mag much simpler....."

FYI- Don't know if tis will make your life any easier, but you do have options. This is from the "tips and tricks" section of the E-mag website:

  • Series 113/114 (four-cylinder) remote coil option – The high-voltage coil makes up the back half of the ignition length and is attached with four case screws and the 3-pin green coil plug. If clearance is tight/impossible behind the ignition, the coil can be separated and remote mounted elsewhere. Splice 16-gauge wire to extend the coil pig-tail and reattach the green coil plug. Mount the coil at a more convenient location. Some have fashioned a coil mount on the firewall or on a bracket they made for placement behind the oil pan. From this lower oil pan location, routing shortened plug leads to the lower spark plugs will further clean up the accessory area. The ignition head remaining in the mag port is now less than 3” deep (half of the original).
 
I had dual P-mags on my second RV8, and I think that green connector is the weak point in the system. Doesn’t seem very “aviation” - more like a computer part. I think tinning the ends of those wires will make it a little more robust, but still substandard as far as a connector connected to your Lycoming. I had trouble with those guillotine connectors coming loose too. I agree, making sure you clamp the wires as Dan suggests should help, but it’s still doesn’t seen like a very good connector for an aircraft engine.
 
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"Small ferules" = d-sub pins. Lots of folks have the appropriate crimper.

Now, does your installation incorporate an adel clamp to fixate the wiring harness to the p-mag body, before it goes to the green connector? Folks who hang wires from connectors, flopping in the breeze, really kinda deserve broken wires.
Yes my install does incorporate the adel clamp. My wires were fine before removing the control plug several times for the annual inspection. Before I put the nose bowl back on I'm gonna install some small ferules so I don't encounter this again next year.
 
I had dual P-mags on my second RV8, and I think that green connector is the weak point in the system. Doesn’t seem very “aviation” - more like a computer part. I think tinning the ends of those wires will make it a little more robust, but still substandard as far as a connector connected to your Lycoming.
I agree, it's crazy they are still using these when there are so many better choices available.
 
Just in case someone needs a replacement P-mag connector...

I used Ferrules and heat shrink. Each connector has a heat shrink tube then the whole harness has a heat shrink tube.
Larry - have you ordered this part number from Digikey and had success with it fitting a P-Mag? I've just purchased a P-Mag on the secondary market and it didn't come with the connector. I really appreciate you posting this link - I just want to make sure I order the right part.

Thanks a bunch for sharing this info.
 
Larry - have you ordered this part number from Digikey and had success with it fitting a P-Mag? I've just purchased a P-Mag on the secondary market and it didn't come with the connector. I really appreciate you posting this link - I just want to make sure I order the right part.

Thanks a bunch for sharing this info.
Yes. I ordered one thinking I would make a testing harness. It fits. It's not fun removing the connector so I extended the data wires from both P-mags into the cabin to a D-sub female. A male D-sub with a jumper is attached for normal operations. The female can be connected to a computer when needed. I plan to set them so the B-curve matches the A-curve. That way, if a D-sub happens to get loose, the P-mag will run the same timing.
 
Love my P-Mags. Call Brad at E-Mag (name of Company, but now they only sell P-Mags). Brad is great and generous w/ his time.

If I recall the conversation, I asked Brad about the 100 hr. It is an over abundance of caution. Period. The bushings can wear but people report 1000 hours, no issue, still going strong. It's like why do ignition check at runup? It's always good. Cautious. I sydoect thete are tolerances where it may still work but not be within Spec. You just don't want looseness on the gear shaft.

Not part of E-Mag is the EI Commander. EI Comander is in cockpit panel mounted monitor for your P-Mag. Apparently according EI commander it can detect play in the bearings without removing. I suspect by monitoring the timing and looking at changes or variations with itself and between dual P-mags. This is not E-Mag saying this.

Many folks extend the maintenance intervals on their P-Mag. This is common at airlines. If an inspection history shows no issue on a spacific part they may extend, but keep an eye on it. If extended maintenance intervals are good they make that the new program.
 
Is the p-mag gasket the same as the Slick magneto one?
Brad from P mag says: "You can use any standard Slick/Champion gasket. If you use a Bendix style it will have an elongated shape that you can still use if you trim off the ears."
 
Yes. I ordered one thinking I would make a testing harness. It fits. It's not fun removing the connector so I extended the data wires from both P-mags into the cabin to a D-sub female. A male D-sub with a jumper is attached for normal operations. The female can be connected to a computer when needed. I plan to set them so the B-curve matches the A-curve. That way, if a D-sub happens to get loose, the P-mag will run the same timing.
Thanks for this confirmation. Time for me to place an order!
 
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