P-Mag troubleshooting

tkatc · #1 06-19-2012, 12:14 PM

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?

Omega232Devils · #2 06-19-2012, 12:22 PM

Check your ground wire. Make sure you have a great connection to the pmag and to the engine itself. Very important.

drill_and_buck · #3 06-19-2012, 12:55 PM

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.

Mile High Relic · #4 06-19-2012, 01:04 PM

If it was a bad gear you would be in bigger trouble, and the engine would be very unhappy.

Assuming all the electrical connections are still intact, I'd say the PMag failed internally.

Installation manual: http://www.emagair.com/Manual%20LC114v20.pdf

N941WR · #5 06-19-2012, 01:51 PM

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.

tkatc · #6 06-19-2012, 02:12 PM

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...

loopfuzz · #7 06-19-2012, 08:08 PM

Quote:

Originally Posted by tkatc

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...

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.

ao.frog · #8 06-20-2012, 12:22 AM

..... 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%20Servi...in%203_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.

tkatc · #9 06-20-2012, 11:10 AM

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.

tkatc · #10 06-25-2012, 05:36 PM

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.