lostpilot28

lostpilot28

Well Known Member
I'm looking for some additional troubleshooting steps. I taxied out to the run up today to go flying, and I started on my P-mag checks at 1600 RPM. I had the right PMag completely off and when I switched the left PMag to "Internal Power", the engine quit. I repeated this about 6 or 7 times, completely cycling Master Power each time.

My P-Mags are wired the same as Bill Repucci's and I can't see how this would be a loose wire or grounding issue. The reason I say that is because the Left Mag runs fine on ship's power (with the Right Mag off). The engine only quits when I put the left Mag on Internal Power.

Any ideas? Thanks in advance!
 
The symptoms you describe indicate that the internal power generator is not functioning. It should be functioning above 900 rpm or so. Do you know the cut-off rpm for each of your P-mags?

If not, start at a higher rpm (consistent with safety). If the engine runs on the left mag with the mag (ship's) power disconnected, start reducing rpm to determine the rpm where the internal power generator stops. This should be known for each P-mag.

If the P-mag doesn't run at all at any rpm on it's own power, the internal power generator is not functioning. Contact Emagair.

Bevan
 
Thanks for the replies. Bevan, I was running at 1600 RPM or above during my run up. I think mine cut out at 800 or so.

Bill, I got your e-mail...I'll probably call you tomorrow.
 
To clarify, Emagair's instructions indicate that the P-mag will self generate power starting at about 1500-1600 RPM. Then it will continue to produce enough power down to it's cut-off point of about 900 RPM.

Perhaps your P-mag's internal alternator is not functioning OR it has not started yet because it's "take-over" RPM set point has not been reached. I might try it again with a run-up of whatever your brakes can safely hold.

Otherwise, call Emagair.

Let us know what you find the problem to be.

Bevan
 
Do you have 113 or 114 series P-mags?

Also: off which P-mags do you take the tach? Based on what you write, it sounds like the right one?
 
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Bevan said:
Perhaps your P-mag's internal alternator is not functioning OR it has not started yet because it's "take-over" RPM set point has not been reached. I might try it again with a run-up of whatever your brakes can safely hold.

Bevan
Click to expand...

Hi Bevan, I've got 130 hours on the airplane with these P-Mags and it's never done this before. I don't think this is the problem, otherwise I would've seen it at some point in the past couple hundred flights. You do make a valid point, however, because I was under the impression that my P-Mags started generating power anytime they were over their minimum RPM of around 800. I'll have to research this further.

ao.frog said:
Do you have 113 or 114 series P-mags?

Also: off which P-mags do you take the tach? Based on what you write, it sounds like the right one?
Click to expand...

They are 113 Series. I believe it is the right P-Mag, but I'll have to double check. I probably did set it up for the right....I'm just not sure.
 
Same or similar problem

I've had a situation where occasionally after start, I'll check my Pmags for operation and one of them doesn't work. I don't think it's an internal alternator issue, I think it just doesn't initialize when it starts up. The only way I know this happens is when I turn off the other Pmag. To correct, I have to shut down and power down the airplane, then start over. Never had it happen more than once in a row, and less than 10 times in the last 3 years, if that. I have 113 Pmags with software updated in the last 3 years.
I had this problem 4-5 years ago, but a software update took care of it. Came back, and I haven't seen a common thread to troubleshoot.
Not really worried about it, since it has only manifested itself on initialization.


Seb Trost
RV-7A
Boulder City, NV
 
Update

Just wanted to post a quick update on my P-Mag issue. I spoke to Bill R. on the phone Sunday and he mentioned swapping the switches to verify they weren't the cause of the problem. Great idea! I did that today and looked at the wiring again, but it seemed alright. Thanks to Bill for spending time on the phone to help a felow RV'er!

I also got an e-mail from Brad and E-Mag Ignitions and he said it sounded like the internal generator so send it in and they'll take care of it. He actually said to send them both in and they'll check them out! Great customer service like that is hard to find.

I don't expect to get them back for a couple weeks, but I'll post another follow up (in case anyone is interested).

Edit: Seb, I meant to reply to your post as well...I've seen the same thing that you've mentioned on 2 different occasions. They both happened in the first 50 hours that my airplane has been flying, but I haven't seen it since. Brad told me that he hasn't heard of that happening since they fixed an earlier firmware that was sensitive to a weak battery (ship's power) prior to the alternator kicking in. Cycling master power fixed it both times and I didn't worry too much about it.
 
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So we can "Oficially" reset the zero time since failure clock
The "it must be your wiring " was the problem clock
And finally the "you need to update the software" clock

No ignition is fail proof, panecea does not exist.

I'm fair and balanced
 
Epepperman said:
So we can "Oficially" reset the zero time since failure clock
The "it must be your wiring " was the problem clock
And finally the "you need to update the software" clock

No ignition is fail proof, panecea does not exist.

I'm fair and balanced
Click to expand...

Well, I'm not sure anyone was claiming that PMags are failure proof. But, I think it's a fantastic ignition that's super easy to install and maintain. I don't know this for a fact yet, but I don't think they're going to charge me to repair it, and it's over 3 years old. That says a lot about a company.
 
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