danny

Well Known Member
Friend
My motor was acting funny when throttled back in the pattern. No popping or weird drama, just an uneven idle. It's never done this before. I ended removing the mag and discovered a very small but perceptible amt of play in the shaft. Book says as much as .030" (?) is ok. Danny says no. Asking the brain trust what your thoughts are.
Thanks
danny
 
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Very common problem with pmags. the play messes with the internal sensor gap and you have issues. Needs to be sent in for repair. Be sure your sitting when looking at the new repair rates. have no idea what amount of slop in the bearing is allowed, but if it has already translated to poor performance then the spec doesn't matter.

Are you sure ignition is the source of the rough idle?
 
My motor was acting funny when throttled back in the pattern. No popping or weird drama, just an uneven idle. It's never done this before. I ended removing the mag and discovered a very small but perceptible amt of play in the shaft. Book says as much as .030" (?) is ok. Danny says no. Asking the brain trust what your thoughts are.
Thanks
danny
When I called E-Mag, they said any discernible play was unacceptable and needed to be sent in for a rebuild. My P-Mag has been at the Hartzel rebuild shop since May 7th for rebuild.

Edit: 250 hours on my P-mag 😰
 
When I called E-Mag, they said any discernible play was unacceptable and needed to be sent in for a rebuild. My P-Mag has been at the Hartzel rebuild shop since May 7th for rebuild.

Edit: 250 hours on my P-mag 😰
The .030" is from the troubleshooting guide. 105 hours. We're you quoted a $$ amount? Really poor timing here. The airport is going to close for a couple of months starting in July so I was hoping for a bit of flying before that. Did you have any symptoms or were you just doing your annual? Pmag went from hero to zero overnight.
Thanks
danny
 
Very common problem with pmags. the play messes with the internal sensor gap and you have issues. Needs to be sent in for repair. Be sure your sitting when looking at the new repair rates. have no idea what amount of slop in the bearing is allowed, but if it has already translated to poor performance then the spec doesn't matter.

Are you sure ignition is the source of the rough idle?
99.9% sure. The T/S guide says .030" is max. I don't like any amount. It was uneven and almost died on the ground without giving it a little stick. Checked plugs maybe 7 hours ago. My motor doesn't run rich. Filter is good. All the other stuff is good. I have an engine monitor and will download later. Mag is an obvious potential issue. Hopefully the only one. And, yes, will be sitting maybe with an adult beverage to cushion the blow.
danny
 
Can’t find any quantitative reference to the end play other than “excessive play” in the current 114 manual or troubleshooting sections
 
Can’t find any quantitative reference to the end play other than “excessive play” in the current 114 manual or troubleshooting sections
Me neither but the factory told me any play you can feel when aggressively wiggling the shaft indicates the need for overhaul.
 
Can’t find any quantitative reference to the end play other than “excessive play” in the current 114 manual or troubleshooting sections
"You might detect (feel or hear) a small outward shift in the position of the shaft. The expected movement is rather small - 0.030” or less." from the trouble shooting tips on the website.
dk
 
My neighbor just went through P-mag overhauls after some hot start issues that caused backfiring through the induction system. He sent both off for overhaul, and the problem seems to be gone. Seemed like about 3 weeks to a month for the overhaul. Yes, it was expensive. Slop in the bearings was mentioned, but I don't know details..He may chime in if he is watching this thread. I'm old school and just run good old Bendix mags...seems like P-mags are having issues, but I don't have deep knowledge of them.
 
Please post what Hartzell does for you in turn around and cost. I know Brad and company turned P-mags in two weeks including shipping. The cost was reasonable, and in one case upgraded both my boards for the price of one.

One month already and no word? This is not good. I really want to know cost...
 
Please post what Hartzell does for you in turn around and cost. I know Brad and company turned P-mags in two weeks including shipping. The cost was reasonable, and in one case upgraded both my boards for the price of one.

One month already and no word? This is not good. I really want to know cost...
I think this was directed to me.

It was supposed to be shipped yesterday. The charge showed up on my CC but no word from Hartzell. The rebuild cost is $899. They say this includes a redesigned bearing stack and all new electronics. Also the shaft wiggle test goes from 100 hrs (or annually) to 500 hours. Hopefully they really did redesign the bearings and eliminated that problem.

PS: when I sent it to them they quoted 2 to 4 weeks depending on work load, first come, first served. I asked if I could pay full price to ship one immediately and refund the difference but they said "buy a new one or wait for the overhaul"
 
99.9% sure. The T/S guide says .030" is max. I don't like any amount. It was uneven and almost died on the ground without giving it a little stick. Checked plugs maybe 7 hours ago. My motor doesn't run rich. Filter is good. All the other stuff is good. I have an engine monitor and will download later. Mag is an obvious potential issue. Hopefully the only one. And, yes, will be sitting maybe with an adult beverage to cushion the blow.
danny
Monitor said #1 egt is 30-40 degrees lower than the other cylinders below approx 2000 rpm. Spread between the others is about 6-10. Above 2k egt evens out. I think the pmag is drifting at low rpm. I don't think it's a plug or injector but I'll clean the injector and look at plugs just in case.
danny
 
I think this was directed to me.

It was supposed to be shipped yesterday. The charge showed up on my CC but no word from Hartzell. The rebuild cost is $899. They say this includes a redesigned bearing stack and all new electronics. Also the shaft wiggle test goes from 100 hrs (or annually) to 500 hours. Hopefully they really did redesign the bearings and eliminated that problem.

PS: when I sent it to them they quoted 2 to 4 weeks depending on work load, first come, first served. I asked if I could pay full price to ship one immediately and refund the difference but they said "buy a new one or wait for the overhaul"

Assume this was for one P-mag not two and you had an older P-Mag version, with older board *, original bearing ** .

For $899 they upgraded the circuit board and put the larger bearing in? That is good news, as they did not force you to buy a new P-Mag. Turn time was as promised 2-4 weeks ISH.... That is OK.

The cost although not cheap is not outrageous, considering all they did. I recall, could be wrong to go to larger bearing they replace the whole housing. Not sure.

* My take on (electronic) boards in P-Mag, for those who care: The original boards I'll call Gen 1.0 were potted and they did away with that, as it was not needed. The newer boards Gen 2.0 (my term) had no potting and some changes in functions, making it easier to repair. Later boards (out for many years) I call Gen 3.0 had some other features, but not critical or readily apparent to user. They may have had more changes than I mention, just my take on it FYI.

** Bearing size, the original bearing works great, still does, lasting past +1000 hours, some 1800 hrs still in service . Some wear out faster. It depends on engine. If your engine is unbalanced, has HC pistons, no crankshaft dampers, more wear tear on the bearing. The upgraded bearing helps but not a must have, like boards are not a must have, if your old bearings works, old board works, fly one.

E-mag recommended every 100 hrs take them out, check for play. Not a big deal. However bearing wear is a thing.

NOTE: YouTube, Canard Boulevard, the channel features a O-360 Lyc powered Cozy. Had rough running engine due to ignition. His Electroair electronic ignition accessory case driven trigger, after +10 yrs I recall, was worn, leaking. He replace the trigger problem solved, The Electroair is not a P-mag. The Electroair has separate ECU and dependent on ships power. Point being bearings wear out.

NOTE: P-mag is SELF POWERED and has ease of installation. You don't have to mount ECU, coils, crank trigger, plus Aux battery power with all the associated wiring . SELF POWERED is a BIG DOT DEAL... No other EI system is self powered. A little (possible) bearing wear, varies by engine, is the trade off. Balance those props boys and girls.
 
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Above: “No other EI system is self powered”. Until the new Champion Lightning series hits the market sometime this year. Yes it’s a prototype at the moment and there may be some growing pains with early adopters. I won’t be the first in line but I’d like to replace my rather complex Electroair and install one or maybe two of these at some point. Sounds dead simple initially with no external power required except for initial start. 2,000 hr TBO and no maintenance (supposedly), geez what’s not to like? Sounds pretty promising……
 
Above: “No other EI system is self powered”. Until the new Champion Lightning series hits the market sometime this year. Yes it’s a prototype at the moment and there may be some growing pains with early adopters. I won’t be the first in line but I’d like to replace my rather complex Electroair and install one or maybe two of these at some point. Sounds dead simple initially with no external power required except for initial start. 2,000 hr TBO and no maintenance (supposedly), geez what’s not to like? Sounds pretty promising……
Did they design for auto spark plugs?
Maybe for standard distributor style wires?
I can't tell. Sounds promising.
 
Above: “No other EI system is self powered”. Until the new Champion Lightning series hits the market sometime this year. Yes it’s a prototype at the moment and there may be some growing pains with early adopters. I won’t be the first in line but I’d like to replace my rather complex Electroair and install one or maybe two of these at some point. Sounds dead simple initially with no external power required except for initial start. 2,000 hr TBO and no maintenance (supposedly), geez what’s not to like? Sounds pretty promising……
It won’t have the ability to advance. They are going after the certified market. And they have had that mag at every show for 4 years saying “we hope to have a PMA within the year”. I think the hold up is probably more with the FAA approval