STC to replace dual mag with two independent mags

rickgn

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Rick G
It's time for me to overhaul my magneto. I have the dual mag in the IO-540-K1G5. Does anyone know anything about this?


It seems I can replace with two independent mags. Could this then qualify to use SureFly replacements?

As-is, it will cost me $2000+ to overhaul what I have. I'd rather go with at least one electronic.
 
If you have a dual mag, you have a K1G5D. If you want to go to two mags, you have to get the K1G5, which is a surprisingly different engine. It's not even as simple as an accessory case swap. The only reasonable time to do it is at overhaul time. Lycoming will trade out a K1G5 for a K1G5D; the G5 is actually a little cheaper. Unfortunately, it's a $70K exchange and 18 month lead time.
 
I think you missed my point. The Aeronautix STC is to replace the IO-540-K1G5D with an IO-540-K1G5. You have to change the whole engine to get rid of the dual mag. It's not a bolt on...it's paperwork to allow you to swap engines. The STC is around $2000, IIRC, which is about the price difference between the G5 and the G5D from Lycoming.
 
Mooney 201 has a similar stc. Yep engine swap different prob governor I believe.
 
@rickgn,
@Jim K has been down this road most recently and is the expert. Check out the LONG thread on his engine woes and repairs.
 
I think you missed my point. The Aeronautix STC is to replace the IO-540-K1G5D with an IO-540-K1G5. You have to change the whole engine to get rid of the dual mag. It's not a bolt on...it's paperwork to allow you to swap engines. The STC is around $2000, IIRC, which is about the price difference between the G5 and the G5D from Lycoming.
Yes, I missed the point.
> The only reasonable time to do it is at overhaul time

Why is this? Is there a problem with doing it a mid life on the engine?

My goal is to look at an alternative to the ElectoAir dual mag, which would be $10K. I was thinking maybe a SureFly and a regular mag might be a better solution, and possibly less expensive.

Goal (2): There are two mags on one shaft. I've never been comfortable with this. The mag overhaul needs done anyway. I hate to keep putting money into an obsolete item.
 
K1G5d swap to K1G5 is not a simple parts swap. It's not take a single dual mag off and put 2 mags on. It's not unbolting an accessory case and bolting a new one on. It's a total engine swap. If you want to swap engines for the K1G5 mid time, you're welcome to do so.

I know of a few electro air swaps uninstalled. There have been issues. Installation is not trivial.
 
Sigh. I don't know how to make it any more clear.
You have to change the whole engine to get rid of the dual mag. It's not a bolt on.

The electroair kit is currently the only way to get rid of the dual mag without an engine swap. From what I hear, it causes more issues than the dual mag. If you have a mid-time engine, your best course of action is to overhaul your dual mag every 500 hours and fly the hell out of it. When that engine is worn out, swap it for a non-D model.
 
Yes, I missed the point.
> The only reasonable time to do it is at overhaul time

Why is this? Is there a problem with doing it a mid life on the engine?

My goal is to look at an alternative to the ElectoAir dual mag, which would be $10K. I was thinking maybe a SureFly and a regular mag might be a better solution, and possibly less expensive.

Goal (2): There are two mags on one shaft. I've never been comfortable with this. The mag overhaul needs done anyway. I hate to keep putting money into an obsolete item.

I believe in a prior thread a mechanic had suggested to Jim that even the cranks are different. So, there is no physical and legal way to replace your current dual mag setup on the engine that you have, as I understand. You need a replacement engine.

That doesn’t mean you can’t try and do modifications and get yourself an STC, but that’s beyond the scope of your question. Sounds like a fun project for an experimental even if not pursuing a new STC.
 
I misunderstood about the electroaire.

You can put a surefly and a conventional mag on a K1G5. You can not do that without swapping out your current engine.
 
I’m not a fan of D mags but after dealing with them and the early AD’s

it seems they have provided much better service than I anticipated.

BUT

They do require maintenance.

Bendix/TCM calls for mag overhauls every 4 years. Slick is similar.

This is regardless of operating time. For most operators this is not

mandatory. IMHO the biggest concern is the Impulse Coupling Spring.

I will not sign off any D-mag aircraft that has more than 4 years on that

item. If it breaks ( and they do) you have a glider. They do not wear out.

The culprit is rust which is something springs cannot tolerate and leads to

cracks. Every time you fly the aircraft the Spring is given a bath of hot

oil which promotes longevity. So the Hangar Queens are the concern.

Some couplings have a more robust Spring incorporated. It may be worth it.
 
I’m not a fan of D mags but after dealing with them and the early AD’s

it seems they have provided much better service than I anticipated.

BUT

They do require maintenance.

Bendix/TCM calls for mag overhauls every 4 years. Slick is similar.

This is regardless of operating time. For most operators this is not

mandatory. IMHO the biggest concern is the Impulse Coupling Spring.

I will not sign off any D-mag aircraft that has more than 4 years on that

item. If it breaks ( and they do) you have a glider. They do not wear out.

The culprit is rust which is something springs cannot tolerate and leads to

cracks. Every time you fly the aircraft the Spring is given a bath of hot

oil which promotes longevity. So the Hangar Queens are the concern.

Some couplings have a more robust Spring incorporated. It may be worth it.
Sounds like as a minimum I need to replace the dual mag pair that I have. I hate pouring money into a bad design.
 
Sigh. I don't know how to make it any more clear.


When that engine is worn out, swap it for a non-D model.
I'm a bit confused. Does this STC convert from the D model to the non-D model? Or are you saying I have to swap engines no matter what? My understanding from the guy who did my last overhaul is they basically take a shell of an engine and build it to the spec. The -D spec just means it has a dual mag. Removing the -D would mean swapping the mag. So I don't understand what exactly this means "remove engine X for engine Y". When it gets overhauled, it's effectively a new engine either way. Correct?
 
How much time on your unit? Hours & years?

I don’t understand “ dual mag pair”?

Overhaul existing unit as I believe new is not available.

Finding a shop that can service them is getting tougher.

ASSURE you replace the capacitors in the cover/harness as well.

“D” and “ non-D” have different gear systems inside. Changing the

Accessory Case is not enough. Other components such as Cranks are

not created equal either.
 
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I'm a bit confused. Does this STC convert from the D model to the non-D model? Or are you saying I have to swap engines no matter what? My understanding from the guy who did my last overhaul is they basically take a shell of an engine and build it to the spec. The -D spec just means it has a dual mag. Removing the -D would mean swapping the mag. So I don't understand what exactly this means "remove engine X for engine Y". When it gets overhauled, it's effectively a new engine either way. Correct?
Yeah, the guy who did your last overhaul doesn't know what he's talking about. The K1G5D and K1G5 are different engine models, and use different crank, crankcase, and accessory case, as well as completely different gear trains. Engine shops can convert between models, but basically nothing from the K1G5D can be used to build a K1G5. Look at the io-540 parts manual (which you can find in a google search), and you'll see how many differences there are. The cylinders, valvetrain, and rods are about the only parts shared.

The geartrain rides on shafts supported by the accessory case and the crankcase, so the crankcase would have to be changed completely. I'm not sure what's different about the crank, but they are unique part numbers despite using the same counterweights and rollers, so there's something different. Obviously a different accessory case, but that's nothing compared to the above. The geartrain parts would add up as well. The cheapest way to do it would be to find a K1G5 or similar model that shares a lot of parts, like a K1A5, and have it overhauled, and then sell your K1G5D as a core. The easiest way to do it is to call Lyco and send them $70k.

By the way, if you want to see what the inside of one of these engines looks like, find my "FFS I need a new hobby" thread. Also, have your mechanic do SI-1560.
 
I'm a bit confused. Does this STC convert from the D model to the non-D model? Or are you saying I have to swap engines no matter what? My understanding from the guy who did my last overhaul is they basically take a shell of an engine and build it to the spec. The -D spec just means it has a dual mag. Removing the -D would mean swapping the mag. So I don't understand what exactly this means "remove engine X for engine Y". When it gets overhauled, it's effectively a new engine either way. Correct?
The stc is just the paperwork to swap you k1g5d engine and put a K1G5 engine in. It is not the paperwork to swap parts or put mags on.

Keep the single drive dual mag. Fly the **** out of it. When youre 18 months away from overhaul. Order a K1G5.

If you don't believe Jim, call Lycoming Monday morning and query about doing the swap. I've heard they want the dual mags out of circulation themselves.
 
they want the dual mags out of circulation
Which is why they'll accept a G5D as a core for a G5, and give you a couple grand discount. Makes the STC "free".

call Lycoming Monday morning
I know this is confusing for those of us who are self-employed, but Monday is apparently a thing called "holiday" :biggrin: and everything is closed, which means that I have to wait for Tuesday to figure out what to do about my sticky rod :(
 
I know this is confusing for those of us who are self-employed, but Monday is apparently a thing called "holiday" :biggrin: and everything is closed, which means that I have to wait for Tuesday to figure out what to do about my sticky rod :(
Not confusing. On vacation and and hopefully coming back (by car)...and it don't matter what day or holiday it is anyway so why pay attention.
 
We need a support group for this. This thread is a great testimonial to what everyone goes through when they learn they own one of these things. I went through this before Jim did. I was on a mission to ditch the dual mag and as he did, I discovered it’s far from a trivial matter and decided to stay the course. I’ve sold that plane since then so now it’s someone else’s problem. But initially you just can’t believe it’s that hard and ignore everyone that warns you it’s a waste of time. Eventually you come to grips with it and then progress on to Stockholm syndrome and learn to love it.
 
I was actually dumber than “realizing I bought a dual mag. I knew what I was buying before I bought it and was convinced I could “fix” it easy, and bought it anyway. Past me is a dumbass. Present me probably is too I just don’t know how yet.
 
We need a support group for this. This thread is a great testimonial to what everyone goes through when they learn they own one of these things. I went through this before Jim did. I was on a mission to ditch the dual mag and as he did, I discovered it’s far from a trivial matter and decided to stay the course. I’ve sold that plane since then so now it’s someone else’s problem. But initially you just can’t believe it’s that hard and ignore everyone that warns you it’s a waste of time. Eventually you come to grips with it and then progress on to Stockholm syndrome and learn to love it.
So....maybe the best course of action is buy one close to overhaul, at a reduced rate for being at tbo and immediately start the exchange process.
 
This is why when did the engine on the Mooney we went with Lycoming factory overhauled engine.

This allowed us to swap the IO360-A3B6D for an A3B6. <- note no “D”, meaning two real separate mags. We we also able to go from flat to roller tappet. Factory is the only way to do this, none of the known engine shops or field overhaul places will be able to do the swap.
 
“D mags” and Dry Vacuum Pumps are a couple of the worst scams ever

dumped on the Light Aircraft Community!
 
“D mags” and Dry Vacuum Pumps are a couple of the worst scams ever

dumped on the Light Aircraft Community!
When we updated our panel some we replaced the King AI and 55X HSI with two Garmin GI 275 and did a vacuum pumpectomy.

We like where we are now, real mags and no vac pump.
 
Bendix/TCM calls for mag overhauls every 4 years. Slick is similar.

This is regardless of operating time.
Slick publishes this: https://www.championaerospace.com/assets/technical/F-1100-SB2-80C.pdf

I don't see any 12-year interval mentioned at all.

Bendix/TCM, in this one, http://www.tcmlink.com/pdf2/SB643C.pdf specifies a 12-year service limit. I note that they have upgraded their 400-hour internal inspection period to 500 hours. Mags built before June 1, 2015 have a 4-year service limit for internal inspection specification.

But all those numbers make no impression on owners that typically run these things until they quit.
 
“D mags” and Dry Vacuum Pumps are a couple of the worst scams ever

dumped on the Light Aircraft Community!
I never had any hassle with dry vac pumps, as long as we installed them and checked them in accordance with the instructions and kept the system filters in order. We always bought the Rapco or Tempest pumps that had the vane wear inspection provision that allows one to run that pump to its safe limit, maximizing hours flown for pump cost, without risking failure. I never had any pump fail on any of our seven airplanes, over a ten-year period (about 35,000 hours, maybe) by doing that. Usually got well over 1000 hours out of a pump.
 
A couple 150’s; one a 66 and another a 67 , both have original wet vacuum

pumps. IIRC I’ve only ever had one wet pump fail. 1000 hrs seems the norm

for dry but I’d rather not have to buy one.

Btw - I’m also a fan of screens or filters in the suction line to protect the

pump. Few aircraft have them.

Newer pumps do have the wear check provision and inlet screens. Took

some time to do so. One guy had a a gyro fail and parts took out the pump.

The a/p followed the gyro winding down. At night with 4 tanks he had just

topped off. He works concrete but battled the disconnect.
 
I own a Saratoga SP that was converted to a dual ElectroAir electronic ignition before I purchased it. I have not owned it long enough to know for sure how reliable they will be over time, but so far they have worked great. If you do go that route make sure you have someone install them that has experience with them, or at least that is willing to spend time learning the system. It is completely different from traditional magneto setups. The install manuals are poor and in some cases inaccurate. The mechanic that did my prebuy looked at the system quite closely and found several items that likely would have caused issues down the road, i.e a bracket that holds the pickup sensor installed backwards, causing reduced clearance on the wire, leading to chaffing of the sensor wire. He also made a call to ElectroAir about certain things in the manual such as the torque specs for the spark plug wires, and was told, don't use what is in the manual that's wrong...

I think the ElectroAir system can be a good option. But they still have quite a ways to go on producing good documentation that will allow the average mechanic to install and maintain it reliably.
 
I own a Saratoga SP that was converted to a dual ElectroAir electronic ignition before I purchased it. I have not owned it long enough to know for sure how reliable they will be over time, but so far they have worked great. If you do go that route make sure you have someone install them that has experience with them, or at least that is willing to spend time learning the system. It is completely different from traditional magneto setups. The install manuals are poor and in some cases inaccurate. The mechanic that did my prebuy looked at the system quite closely and found several items that likely would have caused issues down the road, i.e a bracket that holds the pickup sensor installed backwards, causing reduced clearance on the wire, leading to chaffing of the sensor wire. He also made a call to ElectroAir about certain things in the manual such as the torque specs for the spark plug wires, and was told, don't use what is in the manual that's wrong...

I think the ElectroAir system can be a good option. But they still have quite a ways to go on producing good documentation that will allow the average mechanic to install and maintain it reliably.
I hope it continues to work for you, and would be interested to hear an occasional update. Following the pa32 fb page, there have been a number of failures, which can't be good measured against what probably amounts to tens of installations. As with everything though, you never hear about the ones that work.
 
As with everything though, you never hear about the ones that work.
Yep. One reason I like to ask the manufacturer if theyve got a customer I can talk to. I can read the negative reviews
 
So it looks like the advice is correct. The STC for a Piper Lance covers replacing the engine.


Engine:
STC SA01820WI is available and ready for purchase. The STC is applicable to the Piper PA-32R-300, PA-32RT-300, and PA-32R-301(SP) model aircraft and replaces the factory installed Lycoming IO-540-K1G5D engine with a Lycoming IO-540-K1G5.​
*Note – this STC does not convert an IO-540-K1G5D engine to a 2-magneto system. It replaces the entire IO-540-K1G5D engine with an IO-540-K1G5 engine which is factory equipped with a 2-magneto system.
The STC cost is $800.00 USD. This is for the STC and supporting documentation only. Replacement engine and installation is the responsibility of the purchaser.​

So basically I have to find a core or do a replacement from the factory. $70K replacement vs $50K overhaul. That's a tough one. 4 mag overhauls are cheaper than the difference.
 
$70K replacement vs $50K overhaul. That's a tough one. 4 mag overhauls are cheaper than the difference.
The magneto doesn't need an overhaul every 500 hours. It needs a 500-hour inspection, something much cheaper than an overhaul but still not free.
 
There can be a hidden cost that can make it very pricey.

When you buy new mags from a big box outlet ASSURE all Service Bulletins

are complied with prior to installation. Ideally prior to shipping.

Warranty starts at time of install. Finding you need a new mag at the

next Annual that there were 3 applicable SB’s at installation will not

make you happy. But that is still better than having the Impulse Coupling

fail and trash the engine.

SB’s are available on Aircraft Magneto Service website and other sources.

You need not be a Tech to check this. You do need model and serial

number.
 
Good point. What is the criteria for overhaul vs. just saying it's good to go?
The info is all in the manuals for the magnetos. Try this, for the Slicks: https://www.championaerospace.com/pdfs/techdocs/F1100/L-1363J_corrected 20210420.pdf

Section 3 describes inspection procedures. In that section we see this little remark:

1739839107319.png

Section 4 describes overhaul. In there we see this:

1739839190329.png

If you take one apart, you'll realize that everything except the housing and magnet rotor is getting replaced. They even tell you this:

1739839283662.png
 
I have posted this picture a few times in the past couple years. This is the parts that were replaced during my 500 hour inspection for my D mag. It also received new capacitors and hardware. Also support paperwork/instructions for reinstallation.
I have flown 2 different D mags for total of 1600 hours between 2 engines. I don't have problem with them. They will always go back to the mag shop at 500 hours, just the way it is.
5b102cf2-1dad-4faa-b4b7-231269f65fcc.jpg

Fresh ready to go back on minutes after this picture was taken.
e7937f12-74df-465e-895c-c9a9e500e623.jpg
 
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