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A different P-mag issue

Davepar

Davepar

Well Known Member
Tried to get up for a flight today, but I discovered the left ignition wasn't working during the run-up. Took the cowl off back at the hangar and found this:
IMG_2493.jpg


All of the screws on the connector were a little loose. I thought I tightened them, but it's a little difficult with the tiny screwdriver that is needed to fit the screws. I confirmed there is plenty of slack in the wires for engine movement. The right P-mag wasn't as bad, but I tightened all the screws anyway.

Something to watch for out there...
 
THIS IS WHAT I WOULD DO....

Davepar said:
but I discovered the left ignition wasn't working during the run-up. All of the screws on the connector were a little loose. I thought I tightened them.Something to watch for out there...
Click to expand...
Dave, solder all of the wire ends, then heat shrink back about 3/4" for support. Then make a bracket to come off of that allen screw in the photo and secure all of the wires to the bracket. The set screws could use a little lock tite. They will bite into the soldered (tinned) wires better that just the twisted group. This is not a good connection to use in an aircraft. But you will have to ask the "PEA" mag people why they did this?

fly safe... :rolleyes:
 
Dave, I highly recommend CLAMPING those wires to something on the engine. Even if there's "plenty of slack," you don't want any stress on those wire ends imho. I would isolate any movement of those wires to a stretch between a clamp on the engine side and a clamp on the engine mount.
 
Yes thanks John

....:)

Yes I agree with Dan in fact Emag supply you with a wire bundle clamp that goes on one of the 4 screws that hold down the coil block to the pmag body.

This is a pretty essential way of providing strain relief IMHO

Frank
 
There is an adle clamp on the wires. It's just outside the picture. Unfortunately, it's not quite small enough to hold the wires securely. I need to use a smaller clamp there. Still, I don't think that was the issue. I just didn't screw down those connectors enough.

Tinning the wires is a good idea. I'll add that to the list of things to work on.
 
Steve, great post. I've got to ask though, did Wilber and Orvile prime the inside of their flyer? If so, what kind did they use? :D

Of course an Englishman would have said it in a much more subdued and low keyed manner of sarcasm, something like: It is an experimental isn't it?"

Other than that, insightful, appropriate and GREAT.

Jekyll
 
wow

that connector looks like it belongs on the back of a pc. :rolleyes:
as much as those mags cost seems they would have some better type of connector. maybe even a lowly automotive style weather pack :rolleyes:
tinning will help a ton. you may want to consider back filling the cavity with silicon grease to prvent water intrusion.
good luck
 
Those connectors are good

Nothing wrong with those chap. They work great..As long as you screw them down of course..:)

Frank 7a
 
RVbySDI said:
I think I will actually go with the 300 lb 12 hp engine ole' Wilbur and Orville used. They surely new more than I about the best things to use for airplanes. :rolleyes:

Oh, and while we are thinking about it, why should I even be considering putting any electrical devices on my airplane at all? Hand propping has always worked for those old airplanes why not my RV? We don't need radios to fly. And why bother with GPS? Real pilots can circumnavigate the globe using a compass, the stars and a sextant. No alternator, no starter, no wiring, no electronic ignition, no electric trim, no electric flaps, no lights, no need for powered gauges. Lets see now, that should keep things simple. While we are at it why bother with cowling this wonderfully perfect engine that needs nothing other than a rubber hose feeding fuel to it, a mechanical spark producing device of some sort, a carburetor (you can't improve on carburetors so why even mess with that fancy fuel injection stuff?) and some levers to control fuel flow and air flow?

Those old planes were not cowled much so do we really need to put a cowl on this one? Why are we bothering with flush riveting those skins? Planes flew fine before without that "new" technique. Shoot even this wing design isn't necessary is it? Those old flat winged bi-planes flew just fine with them didn't they?

Altimeter, Airspeed, liquid compass and, to keep the FAA happy, an oil pressure gauge for instruments. Just buck some rivets and don't worry about dimpling anything. For God's sake don't be doing anything experimental with those engine installations! Make sure to use those Lycoming or Continentals in these things and quit tinkering with them! Make doggone sure you use the tried and true magneto on there! Oh yeah, I almost forgot! Make doubly sure you are pumping some high octane AVIATION fuel in it (that is very important too, isn't it? We don't want any bad things to happen because we go and change the chemical composition of our fuel do we? The best fuel in the world is already being used so by god do not mess with that!) That should do it then. Why should anyone ever want to try to improve upon that? :confused:
Click to expand...
As long as you understand that you are the guinea pig here and you accept that. keep right on truckin. My E-Mag and P-Mag came close to destroying my new engine. i only had to pull one cylinder off. Only time will tell how much damage was done. I could replace and engine but I didn't want to get hurt. i wish you all good luck.
 
Adel clamp for wires

Dave:

I just finished up wiring my Pmags.

I put on two sleeves of heat shrink tubing around the wires. This increased the diameter sufficiently enough for the adel clamp to securely hold the bundle.

-Mike Draper
RV-8 Finish
 
Must you be such a wet blanket? If you want tried and true, buy a spam-can. The mere fact that you are flying an RV-9 and not a C-152 tells me that this is not the case. Why not a Curtiss Jenny or a Sopwith Camel? Those were perfectly good planes - why mess with a good thing?

If you can build a better ignition system - go for it. Until then, please don't tell others that their choice is wrong. It is, after all, their choice. The magneto was once dangerously new and untested as well.

Long live EXPERIMENTAL aviation....
 
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I have to agree with you Greg.

John, c'mon man. Seriously, why do you constantly need to harp on others choices? You are a big contributor to this forum, and most of your posts are worth reading. Then you throw in stuff like this. Can't you just let it go? This thread isn't even about EI vs. Mags. Dave had a small problem, so he posted the problem seeking some advise, and you start an argument. It wasn't even a problem with the Pmag!

Whatever. Again, this is probably someplace that I should keep my mouth shut...

Next thing I know, you'll be telling me how horrible a person I am for putting an Egg E6 in my airplane. :rolleyes: MY choice. We are not building airplanes for YOU.
 
cjensen said:
Next thing I know, you'll be telling me how horrible a person I am for putting an Egg E6 in my airplane. :rolleyes: MY choice. We are not building airplanes for YOU.
Click to expand...

An Egg in your airplane? What were you thinking? Don't you know that causes global warming, melting icecaps, and will starve 3.8 million children in Sumatra? :rolleyes:
 
Like I said guys, technology should benefit man, not harm him. As long as these accessories continue to fail regularly, I will continue to trumpet the virtues of magnetos. Have a good day.
 
And that's fine - but you weren't trumpeting the virtues of anything - you were bashing another competing product in a childish and condescending manner. That was uncalled for. Mags fail too, ya know.

'Nuff said - back on topic, please....
 
airguy said:
An Egg in your airplane? What were you thinking? Don't you know that causes global warming, melting icecaps, and will starve 3.8 million children in Sumatra? :rolleyes:
Click to expand...
What? It does? Oh man, I'm gonna be in trouble, aren't I? ;)

:cool:
 
Dave,

Thanks for posting this issue and thanks to the others with suggestions. I've just installed my Pmags and you guys have given me some good ideas on how to secure the wires.

Thanks again!
 
Try Ferrules

You can crimp or solder these hard-tips onto your wires to give the screw clamps something to bite on. Solder can cold-flow under the clamp and can cause the connection to loosen up over time. The other advice about strain relief and clamping is valid and a drop of loctite on the screw threads wouldn't hurt either.

The connector is from Phoenix Contact (or a clone). Have used a ton of it over the years. Good stuff. Mouser stocks the ferrules:

Phoenix Ferrules

You might also find something similar at HD/Lowes. They are commonnly used in control / panelboard wiring with screwclamp connectors.

Hope this helps.
 
1 pea mag in a plane

gasman said:
Dave, solder all of the wire ends, then heat shrink back about 3/4" for support. Then make a bracket to come off of that allen screw in the photo and secure all of the wires to the bracket. The set screws could use a little lock tite. They will bite into the soldered (tinned) wires better that just the twisted group. This is not a good connection to use in an aircraft. But you will have to ask the "PEA" mag people why they did this?

Why not have one super smart polyelastic electronic plastic mag and one real magneto? When the one that is going to break, breaks, you just keep flying.
Click to expand...
 
Locktite?

:confused: Won't the locktite eat the plastic body of the plug? Be careful! I don't know if it is typical or not, but I have had issues before where I used locktite with something that was holding plastic - a lens on a taillight on my motorcycle, and it ate into the plastic to the point I had to replace the lens. :eek:
 
phil9diesel said:
Why not have one super smart polyelastic electronic plastic mag and one real magneto? When the one that is going to break, breaks, you just keep flying.
Click to expand...
If and when one P-mag breaks, I'll still keep flying. The two P-mags are independent units. I can loose power to both, one can fail, and I'll still be flying along. I've balanced the risks and the benefits, and I'm happy with my choice.
 
Its not up to aerospace standards

Never liked this computer / terminal strip / electronic board set-up for critical connections in an engine compartment.

I thought he changed the design?

Any way look at a military Cannon plug and look at this. To say there is nothing wrong with it, I'd have to disagree strongly.
 
Dave:

Thanks for starting this thread. I wired up my e-mag and p-mag tonight and was struck with a gnawing feeling that I should be tinning the wires. Good old search feature.

Ok, have folks tried locktite on the connectors? If so, what are the results? Safe with the plastic? I got locktite on a d-sub backshell once and found it the next day dissolved into a pile of crumbs. I'm way past the point of being leery about using it on plastic without first knowing it is safe.

Jekyll
 
Don't tin

I've had Pmags since the get go. I now have 230 hours now and have had two failures in flight. I switched over and finished the flight. One was mechanical when a magnet housing failed causing an major advance. The other was recent and it hasn't been returned yet to find the cause.

Despite the issues I like the product. Brad and Tom a very receptive to input and are willing to change to make positive improvements in the product.

Regarding the wiring situation, do not tin the wires. They will break for sure. One thing you can do is strip off a 3/8" of insulation, fold it back over itself and then insert into the port and secure. this works great. A friend tinned his and had a wire break in very short order!!!

Here are a couple of my recent recommendations to them.

1) Do away with the "quick time" method of timing. They are easy enough to time manually. Some of the recent issues have only occurred after the blow timing method was developed. They do need to insure that the green light will come on when the gear is in a detent however and not on a high spot.

2) Consider another method attaching the wires. Although I haven't had any issues with this method the potential is there. There are many viable posibilities.

3) Do something with the gasket!!! This is very frustrating to get everything set up and ready to install only to have the gasket fall off the lip. I've tried many methods to hold it in place with only marginal success. I suggested they go to gasket that has lugs on it to go over the mounting studs on the engine.

I was advised they might to to an O ring in the future.

4) Design and install a system that will allow the end user to make updates to the unit with a laptop and the Internet. This will avoid the remove/replace and send in for updates.

We'll see. At least the company is extremely receptive and truly desires to make the best possible product.
 
RV7Guy said:
3) Do something with the gasket!!! This is very frustrating to get everything set up and ready to install only to have the gasket fall off the lip. I've tried many methods to hold it in place with only marginal success. I suggested they go to gasket that has lugs on it to go over the mounting studs on the engine.
Click to expand...
FWIW, when I'm reinstalling my mag, I put a tiny dab of DC-4 (or even just a fingerprint of oil) on the gasket/flange and it stays put a little better.
 
RV7Guy said:
3) Do something with the gasket!!! This is very frustrating to get everything set up and ready to install only to have the gasket fall off the lip. I've tried many methods to hold it in place with only marginal success. I suggested they go to gasket that has lugs on it to go over the mounting studs on the engine.
Click to expand...
I will use GASKET COMPOUND (Permatex, RTV, or Form-a-gasket) on the gasket where it attaches to the mag. Make sure that you have OIL on the other side where it touches the engine. Gasket now stays with the MAG when you pull the mag out.
 
Don't be a Tin Man

Tinning wires - followup:

I discussed this with the folks at E-mag and was told NOT to tin the wires. The added stress points outweigh any benefit.

Jekyll
 
Pmag issue followup

Turned out the rotor magnet was hitting the sensor and had caused a displacement shift.

Frank 7a
 
Thanks for the followup Frank. Sounds like a solid mechanical failure. Not software voodoo.
 
I have some more P-mag info that I can share:
I just got my P-mags back two days ago from more updates (v.25) and to my surprise, the "blow-in-the-tube" mechanism is totally disabled. I was trying to just erase any stored position before mechanically timing. I called Brad after a couple of hours thinking I had done something wrong and he confirmed that they are currently temporarily disabling that functionality while they... I didn't ask him to go into too many details. I happily timed them how I was intending and rocked on. I'm personally happy that I now have units that can't be timed via the manifold pressure tube.
Just some more data for the record.
 
Same with mine

frankh said:
Turned out the rotor magnet was hitting the sensor and had caused a displacement shift.

Frank 7a
Click to expand...

Hi Frank,

The housing that holds the magnet broke loose on mine causing the rapid advance. I switched mags and flew on.
 
Good!!!

scard said:
I have some more P-mag info that I can share:
I just got my P-mags back two days ago from more updates (v.25) and to my surprise, the "blow-in-the-tube" mechanism is totally disabled. and he confirmed that they are currently temporarily disabling that functionality while they... I didn't ask him to go into too many details. I happily timed them how I was intending and rocked on. I'm personally happy that I now have units that can't be timed via the manifold pressure tube.
Just some more data for the record.
Click to expand...

After my failure and Mark Chamberlins failures I recommended they do away with the "blow timing." Although not a scientific process, it seems that most of the failures occurred after the quick time method was introduced. Maybe they listened to this.

They just need to insure that the mags will time with a green light on a low spot when the gear is turned. One of mine would get the green light on a high point. Any bumping would knock it off time. Unfortunately, this was the left mag and I couldn't turn it enough once engaged to get the green light back because of the oil cooler lines and engine case. What a pain in the arse.

Sounds like they are headed in the right direction. I continue to believe in this technology. A friend recently had far more problems with his electronic ignition than I've ever had with my Pmags but because his system has been around it didn't get any press. This despite two emergency landings!!!!
 
Terminals

I have not bought an engine for my RV-6 yet, but was considering P-Mags. I really like the concept.

This is my first look at a picture of the terminal setup, and I'm concerned. I am an engineer with past experience with what I think are these exact same terminals. I believe the terminal vendor would state that this design is suitable for a static installation only. If these are the terminals I am thinking of, they are designed to go into a control cabinet where wire density is a concern and vibration is not. I expect there will be lots of failures as hours on these installations mount. Several posters are correct about tinning the wire as well. Due to vibration, there will be a stress concentration point where the solder ends. The wire will work harden and break just behind the solder unless the wire is totally immobilised. Even still, I would not be comfortable with this terminal being used for any critical connection in an airplane, much less in the engine compartment.

I don't know the guys at PMAG , but I think they should put an urgent effort to re-engineer this termination and issue a mandatory feild retrofit before someone gets hurt. There are many suitable automotive types available that would fit quite nicely.

Sorry for speaking so strongly on this issue and re-iterating points others have made, but I genuinly beleive this is a serious safety problem.

Dale Lambert
RV-6 finishing kit
 
Terminal block

Although these don't appear the best application for the purpose, I have not had any problems with this. A block with "Fast on" terminals would be much better.

The Advanced Systems brain box for the engine monitor is the same system only smaller screws and ports. There's got to be at least 20 wires into that box. No issues at all.

What you might be missing from the big picture is an adel clamp near the terminal block. The wires are ran through the adel then inserted into the block. I secured the wires on each side of the adel with zip ties. There no lever or way for these wires to start and vibration.

I had thought of putting a dab of Goop on each wire at the block and on each screw port to lock things in place, but I haven't had any issues with this at all.

We might be overthinking this ;)
 
What the?....

Hey guys,


Just got my latest Pmag back....Cleared the offset timing (blow in the tube to get the red flashing LED, cycled the power, found the green spot), installed and went flying...So far so good.

Had the cowl off this evening, thought Id better double check the timing...Turned power on with P lead grounded and.....the LED flashed RED....What?...Cycled power and it came back still flashing red.


I've Just gotten this unit back, I didn't try to start the motor and I can't see any reference on the emag website.

Anyone have any clue?

Thanks

Frank 7a...
 
It turns out

This is a new issue...Or at least one the Emag boys have not seen before.

They have asked me to run a diagnostic check and they are sending me a new unit in the meantime.

Frank
 
P-MAG

When you put power to the mags they are in the setup mode.
Unground the p-lead will put the mag into run mode.
You should get a green lite at 25% before top dead center.
Be carefull the mags are HOT at this point.
Rich
 
I'm sure happy I'm running my dinosaur mags.

While I'm planning my trip to the 69th latitude in the Arctic in the next two weeks, I'm sure happy I'm running Slick's.

I rarely hear the E/P-mag or Lightspeed stories from the large fleet of airplanes using the old technology. If you do have a problem there will probably be someone around the 69th latitude to help fix my mag, without having to wait for something to be shipped up from the lower 48. They probably have an aircraft mechanic in Tuktoyaktuk.

JT
 
frankh said:
This is a new issue...Or at least one the Emag boys have not seen before.

They have asked me to run a diagnostic check and they are sending me a new unit in the meantime.

Frank
Click to expand...
Frank,

Any word from the "Emag boys"?
 
Funny you should ask

N941WR said:
Frank,

Any word from the "Emag boys"?
Click to expand...


I sent them an email this morning asking them what they found. Have not heard back yet. The unit was clearly still malfunctioning when I stuck it in the box. It was also clearly a failure mode the Emag boys had not seen before.

It seems to have dropped back into the flashing red LED mode. This is not possible. the good news at least is that it stayed there thru several power cycles.

Naturally Emag were keen to study this new creature.

Both my new Pmag and Emag run flawlessly to and from Co I'm pleased to say.

frank
 
My P-Mag issue

Frank and others running P-mags:

I post not to trash E-mag Air as I still think they have a great product and will figure all this out.

On Sunday, August 5th I had my first flight. My RV-9 is equipped with an O-290-D2 and duel P-mags wired per Bob Knuckles. Here is my wiring diagram.

On the second flight of the day, my the airplane wasn't developing full power and my CHT's were heading towards meltdown. This happened while taking off and I made and abbreviated pattern (500' AGL) and returned for a landing.

After investigating the cause for the high CHT's and lack of performance, we discovered the left P-mag was out of time. I re-timed it and the engine ran just fine. My third flight of the day was uneventful.

Upon calling the E-mag Boys they said there was a new firmware upgrade that they developed after they announced their June SB (I shipped my P-mags back and had this service bulletin done prior to the first flight.) and before OSH. Unfortunately they didn't announce this upgrade to anyone.

This pre-OSH fix is supposed to resolve the timing loss issue.

Brad told me that wiring my P-mags per Bob K's diagram is the cause of the problem. Apparently if you drop power while grounding the P-mags and quickly turn them back on, there is an internal check that may overwrite the timing mark, or something like that. This new firmware upgrade is supposed to resolve this problem.

I'll keep you informed.

(Please, no posts about why a traditional mag, Light Speed, etc. is better than a P-mag. Those comments help no one. We have these things and are trying to have an open discussion to resolve these issues, not bash P-mag or anyone else. - Thanks)
 
Bill, I chose to not use the Knuckles switch setup for just this reason. E-Mag has always recomended power on before P-lead change. Haven't flown mine yet but gitt'n close!

Larry
 
Bill, it sounds like you're talking about v.26 which I am now running on both of my units. I haven't had any timing issues, but certainly did have two units with no spark at all sometimes. Your switching diagram could be a little misleading. I think what you really have is per aeroelectric, with the p-lead change always occurring at a different switch position than power. That is how I'm setup as well. I'm sure glad they have done some re-engineering if they really think that pilot manual switch timing is that big a problem. I also wish they would come up with a way to notify the user population of software or design changes and what those changes are as they are all clearly a safety of flight issue for us.

Bill, did Brad say "...drop power while grounding.", or "...drop power while grounded." IE. at the same time as closing ground, or as a separate operation (which is really what our switches are doing, progressive switching).
 
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P-Mags are back

Gang,

Yesterday my P-mags were on the front porch waiting for me. Included in the box was a letter from Tom telling me one of them had recorded a high temperature and that I should install a blast tube. Funny thing, there is a blast tube and the over temp was radiant heat coming from my over temp cylinders as a result of my left P-mag loosing its timing. Go figure... The note went on to say emphatically not to use the Bob Nuckolls wiring diagram even though the new software upgrade will solve the problem caused by Bob's diagram.

In essence, Tom doesn't want you to test the P-mags in all failure modes. To me this is completely unacceptable. If I can't test them in all failure modes, I don't want them. So, being me, I installed them w/o changing my wiring diagram and added an additional check after doing the mag check. The change includes a full power run to see if I note any change in engine operation.

With that decision made, Nora and I drove to the airport this morning and installed and timed them w/o any issues. A quick engine run-up and three flights later (2.1 hours), all is good.

It sounds like they may have solved the lost timing mark issue.

Since this is your ignition system, it is completely up to you to decide how to wire and test these things.

Would I recommend P-mags to anyone, you bet! I am still sold on the technology and Brad and Tom's ability to resolve issues.
 
You are a prince Bill! I would have melted those mags down last week and made wheel chocks out of them! Best of luck to you!
 
Update - All is good, VERY good!

Sunday I found the time to fly another four flights for a total of 4.1 hours and I?m happy to report the P-mags are working as they should.

As a reminder of how good these things are, while fueling up the -9 I noticed a new 172 on the ramp. The local flight instructor and his student performed the pre-flight dance, climbed in and began the startup procedure. The prop must have spun around 30 or 40 times with a few pauses in between before it finally coughed to life.

The P-mag fired O-290 I have in my -9 starts on the third prop blade every time. (The truth of it is, it is hard to tell how many blades go by since the prop spins so fast and the thing starts just like a car. Hit the button and it is running.)

As far as I?m concerned this issue is closed. Buy a set of P-mags, install them and go fly.
 
N941WR said:
Sunday I found the time to fly another four flights for a total of 4.1 hours and I?m happy to report the P-mags are working as they should.

As a reminder of how good these things are, while fueling up the -9 I noticed a new 172 on the ramp. The local flight instructor and his student performed the pre-flight dance, climbed in and began the startup procedure. The prop must have spun around 30 or 40 times with a few pauses in between before it finally coughed to life.

The P-mag fired O-290 I have in my -9 starts on the third prop blade every time. (The truth of it is, it is hard to tell how many blades go by since the prop spins so fast and the thing starts just like a car. Hit the button and it is running.)

As far as I?m concerned this issue is closed. Buy a set of P-mags, install them and go fly.
Click to expand...
I hope your luck and your satisfaction hold up.
 
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