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PMag Programming?

Tankerpilot75

Tankerpilot75

Well Known Member
Has anyone else experienced problems getting their PMags to enter into program mode for timing purposes? I had dual PMags installed on my engine when it experienced a tear down/rebuild resulting from my 2022 prop strike at AirVenture 2022. Picking it up in March this year I flew it home without any issues. In May I was experiencing a 200 rpm drop doing the mag check. When checking the PMags at that time the left PMag wouldn’t enter into “program mode” so after a few calls with EMAG I mailed the left PMag back to EMAG for warranty work. I was very pleased with the turnaround and it’s subsequent operation.

As some of you who have followed my VAF posts, I have experienced high CHTs and attributed this to the switch to electronic ignition (PMags). In efforts to lower my CHTs I tried “clocking” starting at 2* and later up to 7.5* ATDC. This didn’t lower my CHTs enough. Eventually I bit the bullet and replaced my original rubber baffling with new mil spec silicone baffling and eliminated all possible air leaks around the upper baffles and fabricated two air dams to direct more intake air to the back cylinders. This baffling work significantly improved CHTs so at this oil change I decided to return the timing to 0* TDC as stated in the manual.

When I went to program the timing I again experienced a PMag that wouldn’t enter into “program mode”, this time the right (other) PMag. Frankly this both surprised and annoyed me. Again EMAG, after several tech calls to test the mag they recommended I send it back for warranty work with I did this morning. I expect, as before, they will quickly service it and return it promptly. Their tech support is very good.

My question is: how many of you with PMags have experienced problems getting your PMags to enter “program mode”? Am I the only person who has experienced this problem? Is it possible that I am the only one who has experienced both PMags requiring warranty work? The first one experienced this at around 8 hours. This second one has 46 hours.
 
Do you have the jumper wire installed? I do not, but I have to install it to get the Pmags to go into program mode.
 
I’m just a bit confused by the term “program mode”….do you just mean timing the P-Mag, or something else?
 
Keith, yes jumper wire is installed.

Paul, yes. As you know one has to enter “program mode” to time PMags. Last May the left PMag wouldn’t enter program mode to re-time and had to be sent back to EMAG for warranty work. This week it was the right PMag. It just seems strange that both PMags have experienced the same problem.
 
Tankerpilot75 said:
Keith, yes jumper wire is installed.

Paul, yes. As you know one has to enter “program mode” to time PMags. Last May the left PMag wouldn’t enter program mode to re-time and had to be sent back to EMAG for warranty work. This week it was the right PMag. It just seems strange that both PMags have experienced the same problem.
Click to expand...

Ok, definitely strange….just turning on the power to the PMag with the mag switch off puts it in a condition to set the timing (the manual calls it “setup mode”) with a puff on the hose, and I’ve never had a problem doing that. Once in a great while I won’t get a firm enough puff, but that’s just me not blowing hard or long enough.

What was confusing me was the term “program mode”, which I couldn’t find anywhere in the manual. I do, however, have an EI Commander which allows me to play around with the actual advance curve, and I was wondering if hat was what you were referring to….

Paul
 
Ironflight said:
Ok, definitely strange….just turning on the power to the PMag with the mag switch off puts it in a condition to set the timing (the manual calls it “setup mode”) with a puff on the hose, and I’ve never had a problem doing that. Once in a great while I won’t get a firm enough puff, but that’s just me not blowing hard or long enough.

What was confusing me was the term “program mode”, which I couldn’t find anywhere in the manual. I do, however, have an EI Commander which allows me to play around with the actual advance curve, and I was wondering if hat was what you were referring to….

Paul
Click to expand...

I'm with Paul on this one. Can you explain what you are doing that does not appear to be working?
 
Ok, my bad! I should have used the term “setup mode.”

What I’m doing is trying to enter setup mode following the PMag manual procedure. The first time I tried the right PMag flashed several times then when blank - nada, nothing - no steady light. I tried again several times only to then get nothing. - no light at all. This is exactly the same thing that happened with the other PMag last May.

Called PMag Tech support and followed their guidance inserting a jumper wire between K and G wire ports on the plug. Nothing! Trent at PMag then said to send it in for repair. Like I said earlier - this is the second time but the other PMag. I’m sure EMAG will repair it, I’m just frustrated to have it happen now with both PMags in under 50 hours.

I was just wondering if others have experienced a similar issue.
 
Just turn power off then on again a couple of times to the ‘offending’ p-mag - I’ve seen no red light a couple of times in several hundred hours & realised my method above solves the problem. Worth a try.;)
 
Tankerpilot75 said:
... Trent at PMag then said to send it in for repair. Like I said earlier - this is the second time but the other PMag. I’m sure EMAG will repair it, I’m just frustrated to have it happen now with both PMags in under 50 hours.

I was just wondering if others have experienced a similar issue.
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I have not seen this issue, but since you saw it on both of your pmags, perhaps they were built at the same time and had the same defect? It would be interesting to know what Trent finds - perhaps you can report back?
 
jakej said:
Just turn power off then on again a couple of times to the ‘offending’ p-mag - I’ve seen no red light a couple of times in several hundred hours & realised my method above solves the problem. Worth a try.;)
Click to expand...

Did that. No joy!

Mickey, will do.
 
Firmware version?

Check your firmware versions.

There was a change in accessing the setup mode with FW40 that makes the led go dark if the prop is moved at all after power is applied and you try to enter setup mode.

This was quite confusing when one of my units had been updated but not the other.

Before this update you could move the prop after initiating setup mode. It has been quite a while since this update though.
 
[email protected] said:
Check your firmware versions.

There was a change in accessing the setup mode with FW40 that makes the led go dark if the prop is moved at all after power is applied and you try to enter setup mode.

This was quite confusing when one of my units had been updated but not the other.

Before this update you could move the prop after initiating setup mode. It has been quite a while since this update though.
Click to expand...

What’s the work around for this?
 
There can be some slop in the gear train, and if there is a wiggle of the prop I think the P-Mag can get confused. I think the manual addresses this by making sure you only rotate the prop in one direction towards TDC (or a few teeth after).
 
EMAG Ignition is sending my PMag back to me. They couldn’t find anything wrong with the mag. I am confused but won’t say they’re wrong because I’m not the best engine guy there is when it comes to timing - even on something as simple as a PMag.

They are sending me a new green plug just in case there’s something wrong there. Hopefully after I reinstall the PMag it will miraculously enter setup mode. The wonders (frustrations) of electronics!
 
Tankerpilot75 said:
EMAG Ignition is sending my PMag back to me. They couldn’t find anything wrong with the mag. I am confused but won’t say they’re wrong because I’m not the best engine guy there is when it comes to timing - even on something as simple as a PMag.

They are sending me a new green plug just in case there’s something wrong there. Hopefully after I reinstall the PMag it will miraculously enter setup mode. The wonders (frustrations) of electronics!
Click to expand...

That is actually good news for the 1000s of us out here holding our breath. :)

One thing to try when replacing the green plug is to look at this post:

https://vansairforce.net/community/showpost.php?p=1517458&postcount=39

Jim Ellis had some pmag issues which were related to the wiring connections to the green plug, and found a very good solution.
 
Is it possible you are just not blowing hard enough to enter set-up? I have had that problem. Fortunately, my buddy played tuba in college . . . :rolleyes:
 
MED said:
Is it possible you are just not blowing hard enough to enter set-up? I have had that problem. Fortunately, my buddy played tuba in college . . . :rolleyes:
Click to expand...

My problem was “not getting a solid red light” indicating it was in setup mode ready for the two hard blows. Believe me, I may be old but I can still “blow sufficient hot air.” 😁
 
Final Update on PMag and MP Sensor Issues

I received my PMag back from EMag Ignitions about two weeks ago. I also had to order a new MP sensor from GRT due to the inability to recalibrate the existing sensor. The new MP sensor arrived within a few days of the PMag.

I’ll refresh the situation for everyone so that you can better understand how this all began. Last summer I was experiencing high CHTs after my engine rebuild that resulted from a prop strike at AirVenture 2022. During the rebuild I made the decision to upgrade to a dual PMag ignition system since replacing my magnetos were part of the tear down rebuild process. It just made economic sense to do this upgrade at that time.

I picked up my aircraft in Oshkosh in late March of this year when temperatures were quite cool. The trip home identified a number of things I wanted to address. By the time I addressed those issues it was summer and temperatures were heating up. I soon noticed CHTs were running higher than I expected and were constantly exceeding 400* often getting into the 420s. Prior to the rebuild I never saw CHTs above 385 - even on the hottest days! Some folks suggested this was common for break in but they never came down even after 30 hours were on the engine.

Chasing this dragon was a summer long process. I put a washer behind #3 because it was the worse offending cylinder. I removed the small washer and tried a bigger one when temperatures still stayed high. I then “clocked” the PMags timing starting at 2* ATDC, then 4* ATDC when temperatures didn’t stay below 400*, then increased it to 7.5* ATDC. These timing adjustments helped but didn’t solve the problem. While I was doing this I posted several times on VAF and got various responses and numerous suggestions.

When I posted a picture of my higher CHTs inflight several people suggested my MP reading was about an inch higher than it should be for the altitude and temperature I was at. That led to a month of emails between me and GRT tech support trying to recalibrate my MP sensor. Eventually they said to send it in and they’d look at it and recalibrate the sensor. After bench testing they said it wasn’t acting right and suggested replacing the sensor - which resulted in me purchasing a new sensor. Removal and reinstalling the sensor was a mother bear due to its location and the original builder’s installation technique.

Getting back to the high CHT issue I eventually decided that the only way to truly improve CHTs was to replace the rubber baffling and insure all air leaks in the metal baffling were eliminated. Thankfully Walt Aronow posted a picture of his baffling on one of my threads. I noticed he had two air dams in front of cylinders 1&2 that I didn’t. Using his pictures as my reference I replaced my rubber baffling, manufactured and installed two air dams similar to his and took extra effort to seal up all air leaks. This really made a huge impact with CHTs significantly dropping. I subsequently decided that at my next oil change I would reset my timing back to the recommended 0* TDC.

When oil change time occurred I had already ordered the new MP sensor. After draining the oil I removed the lower plugs and attempted to retime the engine to the 0* TDC. I couldn’t get the right PMag to enter set mode. Called EMAG tech support and even with their assistance I couldn’t get the right PMag to enter set mode. We decided that I would send it back to EMAG for repair. They couldn’t find any problems and returned the mag to me. It was suggested on this sight I use ferrals on the end of my wires attached to the PMag for a better more secure connection. I purchased a kit through Amazon and used them on the reinstall. I won’t say that fixed the problem with entering set mode but after reinstalling the PMag it did enter set mode and I was able to set timing at 0* TDC.

This week I completed the re-timing, oil change and installation of the new MP sensor. Today I test flew the aircraft.

WONDERFUL! Today’s flight validated all the effort and work. CHTs stayed below 350* in all phases of flight - even with timing set at 0* TDC, the lowest cylinder and highest cylinder temperatures stayed within 25* of each other. EGTs were even close to one another. My new MP sensor appears to be working properly too. Time to call it quits.
 
Tankerpilot75 said:
...
WONDERFUL! Today’s flight validated all the effort and work. CHTs stayed below 350* in all phases of flight - even with timing set at 0* TDC, the lowest cylinder and highest cylinder temperatures stayed within 25* of each other. EGTs were even close to one another. My new MP sensor appears to be working properly too. Time to call it quits.
Click to expand...
Thanks for updating us, Jim. I'd say "Time to claim victory!"
 
I don't know if this will be helpful to you now after sending your pmags in for warranty work, But I too have been running dual P mags flawlessly for over 200 hours and 2 annuals, until today when I was unable to get the left Pmag in setup mode to set timing. After Several attempts and lots of head scratching I finally got on the emagair web site and found there good trouble shooting tips not found printed in my manual. 3 reasons for no LED's:1. No 12v power, 2. no ground, or 3. P- lead not grounded.
In my case it was P lead!!!! closer inspection revealed 3 out of 5 wires with broken strands in the control plug. I'm happy to not be sending my P mag in for repair, but kind wish i wouldn't have removed the plug for inspection... It wasn't broke til I fixed it.
Anybody have pics of the D-Sub connectors mentioned by Canadian_joy? Has anyone considered solder tinning the wire ends on the control plugs???
 
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