Mags - Rebuild or just buy new?

WDD

WDD

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Coming up next January at annual my mags will be close to the 500 hour mark. I'm going to install a SureFly to replace the left mag, but want to keep a traditional mag on the right.

Friend was mentioning that he found that buying a new mag was just about the cost of sending out and overhauling.

Not having done mag work before,
1) Is it really cost effective to just buy a new mag?
2) Is there any value to the old mag that I'll be replacing? Anything like the "core" of a run out engine?

Appreciate the helpful hints.
 
Is minimizing downtime important to you?
 
asicer said:
Is minimizing downtime important to you?
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If it is, an exchange through Aircraft Spruce is an option. They will sell you a rebuilt mag, then credit you later when you return the core of your old mag. Don't know how that cost compares with the alternatives these days.
 
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Buy new.
WDD said:
Coming up next January at annual my mags will be close to the 500 hour mark. I'm going to install a SureFly to replace the left mag, but want to keep a traditional mag on the right.

Friend was mentioning that he found that buying a new mag was just about the cost of sending out and overhauling.

Not having done mag work before,
1) Is it really cost effective to just buy a new mag?
2) Is there any value to the old mag that I'll be replacing? Anything like the "core" of a run out engine?

Appreciate the helpful hints.
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To me it would not be worth new, but I have several shops with a short drive.
 
Inspect and replace parts/repair as necessary, don’t rebuild or buy new if you don’t need to.
 
455 Bravo Uniform said:
Inspect and replace parts/repair as necessary, don’t rebuild or buy new if you don’t need to.
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Where does one learn to IRAN mag's? I've done a bunch of stuff, but have no idea how to go about rebuilding or performing an IRAN on a magneto.
 
If you buy new ASSURE you check SB’s prior to installation.

Preferably before purchase.

I’ve found several with 3 outstanding SB’s when they were installed.

The “big box” places do not track this.

Some are serious.
 
Magman said:
If you buy new ASSURE you check SB’s prior to installation.

Preferably before purchase.

I’ve found several with 3 outstanding SB’s when they were installed.

The “big box” places do not track this.

Some are serious.
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Where would you buy a new mag from?
 
It’s not where you buy; just assure SB compliance.

You must know model & s/n to determine applicability.

Bendix generally required a stamped figure but I don’t believe Slick

has any identification system. As you can see; it’s easy to slip through

the cracks. It’s even more of a pain to find after installation.


I like Aircraft Magneto Service as I’ve never had anyone that was not

happy with them. Good website too. I’m sure there are other good ones

too.
 
You may want to start with searching for Slick mag tools.

The T-106 Impulse Coupling is sort of unique in operation

so you will not damage components that a standard Puller would.

Tip from Bendix Manual ( yeah I know) works on most mags:

If the Coupling will not separate do NOT hammer on the Puller.

Instead put a heavy duty soldering iron on the Coupling with the

Puller already at max. Be patient and it will pop off.
 
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I’ve used Aircraft Magneto Service many times. Always excellent service.
Apparently they have some pretty fancy equipment that allows them to test run the mags at operating temperature to check for faults.
Additionally, they were involved in addressing the resistance issues with older Champion plugs. Because of their insights, I now always check plug resistance in addition to using traditional testing methods.

No affiliation here, just a customer.
 
I'll toss another recommendation for an IRAN (not overhaul) from Aircraft Magneto Service. I've used them for my last 2 Slick mags (IRANs) and am about ready to send another. I had them build up a spare mag so when I take one out of service I've got the replacement on hand.

Friends don't let friends buy anything Kelly. Unfortunately, with all the company buyouts/mergers I don't know if it's possible to avoid Kelly parts now that Hartzell owns them. Quality Aircraft Accessories/PowerUp Ignition Systems/Kelly are all under the Hartzell umbrella. No thanks.
 
A bunch of our neighbors and I have had great service from Tropic Air Power in Indiantown, Florida - done right the first time, fair price, fast turnaround. It’s a repair station, and the onwer is very knowledgeable and a straight shooter.
 
I'd be happy with a knowledgeable field overhaul of the old mag. Likely the cheapest and fastest. Since I am EAB I likely could figure this out myself but have never done. I had an AP do them at first inspection after purchase.

For my old 172 it was a rude awakening. The IA was mailing them out, gave me some timeline that was WAY overly optimistic. Had I known I would have gone the exchange route. New/used exchange very similar in price.

I expect they could all be similar in function and would focus on your available options that meet your timeline.

Surefly? Will it be plumbed in to read MP and advance timing? There are some dip switches to play with. Also, the avionics can make a difference, I needed some fancy signal converter. There are pseudo certified surely shops but I found mine not all that experienced. They took their time and did it right though.

I'd read up on the Surefly for your config, discuss at length with the installing shop. You need to know this better than them. Don't trust their confidence...
 
kyleb said:
Where does one learn to IRAN mag's? I've done a bunch of stuff, but have no idea how to go about rebuilding or performing an IRAN on a magneto.
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Both Bendix (TCM) and Slick (Champion) publish service and maintenance manuals for their magnetos. Very detailed.
 
FWIW - I have a set of Slick mags #6310.
 
WDD said:
Coming up next January at annual my mags will be close to the 500 hour mark. I'm going to install a SureFly to replace the left mag, but want to keep a traditional mag on the right.

Friend was mentioning that he found that buying a new mag was just about the cost of sending out and overhauling.
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Hold the bus here. That magneto does not need an overhaul at the 500-hour mark. It needs an inspection, which is far less work. From the Slick Manual:

1782065903736.png
That's the stuff to inspect. Mostly it's the points and cam (they come as a kit) that need replacing; most everything else will reach 2000+ hours if the 500-hour inspections are done properly. The points will likely still be OK at 500 hours, and need replacing at the 1000-hour (second 500) mark. If they're not lasting that long, the condenser is suspect. It needs to be capacitance-checked at 500 anyway.

Now the overhaul stuff:

1782065970424.png

Now, if you know anything about mags, you will see that practically everything except the rotor and magneto housing get replaced. If you buy all those parts they could cost more than a whole mag, and the labor would be on top of that, too.

So, owners need to know that they usually need a 500-hour inspection, unless that mag has 2000 hours on it. That's when it gets overhauled or replaced. Don't spend money needlessly. Don't ask for an overhaul if it's not time for one.

The Slick magneto manual: https://www.championaerospace.com/pdfs/techdocs/F1100/L-1363J_corrected 20210420.pdf
 
I’ll second Dan’s comments and add this.

The Carbon Brush is cheap and I always replace when disassembled for any reason.

#2 reason for dead Slick mags that I see is a broken Impulse Coupling Spring.
Particularly true of Hangar Queens that don’t get fresh hot oil at every start. Per S/M replaced every disassembly.

#1 ? Old coils that have an Open in the Secondary.


FWIW- Currently I’m trying to inventory my “priceless junk”.
Time permitting I’ll post “ stuff” including mag parts and some tools.
 
I know the OP isn't planning on rebuilding or inspecting his mag personally but for those who may, that might not be a well thought out idea. Some jobs are best done by experienced hands. It's been my experience that mags fall into this category. I wouldn't consider the average A&P to complete this job.

One reputable shop is:
Eagle Magneto
386-410-4710
EagleMagneto.com
 
As Dan mentioned, the 500 mark on mags in an inspection, NOT a rebuild. It's 'inspect and repair as necessary'. I also switched to a Surefly SIM6C earlier this year during my annual, but have been inspecting my Slick mags the past few years, and not needed to do a full rebuild, only replace a few parts.

If the shop is saying you need to overhaul the mags every 500 hours, I would push back and ask what specific parts need to be replaced. In the past I have used Shrike Aero. Decent price and usually can get them sent out and returned before my annual on the aircraft is complete.
 
My assumption was that at 500 hours need an overhaul. Learn something here every day.
 
My A&P removed my 497 hours mags and I hand carried them Aero Accessories, Van Nuys, CA. 2 hours later they called me and told me some gears and parts needed to be replaced and gave me a quote, which I approved. The next morning they called me and told me they were ready for pickup. Aero Accessories in Van Nuys can't be beat! Ship them your mags and you will have them back in no time! Best service and best price around! And by the way, they work great!!!
 
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There is a local shop that has been in business for many years that does my mag inspections at 500 hours.
This is what was replaced during the inspection on a D mag. This was not a overhaul. To me it looked like one.
I drive it across town and drop it off. Does take 2-4 weeks though. Those are new capacitors. and hardware.
5b102cf2-1dad-4faa-b4b7-231269f65fcc.jpg

ed302ecb-e876-4a8c-87bd-8e425249b823.jpg
 
ALL magnetos operate on the same principles; but that’s where it ends.

Of the 2 remaining brands:

Necessary special tools are not interchangeable between brands

Parts are not interchangeable as well.

Even lubricants are unique by brand.

The essential “ setting the E-gap” is varies by brand and sometimes
model.

Servicing mags requires a commitment to have the above on hand for
the particular task based on brand/model.

Using the proper engine/mag gasket is essential to avoid Major problems.

Mags with “ears” that mount on studs should have the full gasket that will
hang on the studs. Using one without the “ears” may result in the mag casing cracking that could ultimately cause engine failure.

Using a gasket with “ears” with a mag using hold-down clamps may have
issues as there will be “false torque” with the clamps against the paper gasket.
 
WDD said:
Friend was mentioning that he found that buying a new mag was just about the cost of sending out and overhauling.
Not having done mag work before,
1) Is it really cost effective to just buy a new mag?
2) Is there any value to the old mag that I'll be replacing? Anything like the "core" of a run out engine?
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1. I think not. Last year at 500 hours, Aero ACC in Van Nuys turned around both of my mags in a few days, did the ADs & SBs, at a total cost of $1100. That included some replacement service parts. A single mag would cost about half that - less if it was not the one having the IC. Way cheaper than replacing them.
 
Gary Ward said:
There is a local shop that has been in business for many years that does my mag inspections at 500 hours.
This is what was replaced during the inspection on a D mag. This was not a overhaul. To me it looked like one.
I drive it across town and drop it off. Does take 2-4 weeks though. Those are new capacitors. and hardware.
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I've used Mike Grow for 26 years. I have 2 mags. One on the engine and one spare always overhauled by Mike. He's been great.
 
There are a few service bulletins for Slick mags. In particular, there's one for rivets on the impulse coupling. I've had two QAA rebuilt mags that had issues with those rivets being loose, one was an AOG. The second was found in an annual before it became an issue. I only put in the second QAA because I had no other way to get home.
I'm putting a Surefly at the next annual to replace the impulse coupled mag.
 
I've been looking into this as I'm approaching 500hrs on my mags. As a data point, based upon my limited research a 500hr inspection is coming in between a quarter to a third of what a new mag would cost. Unless money is no object, I'd do the inspection and call it a day.
 
IMHO The place to start is with Make - model- date mfg.

You can then check SB status - AMS. Has on their website.

4200 & 6200 Slicks may need a Coil +.

Once mags are off it’s east to open up and check Secondary resistance.

If circuit is Open you need a Coil.,

That could help the decision.
 
+1 for Eagle Magneto Service at new Smyrna Beach. Excellent work and quick turnaround at a reasonable price.
 
Saratogalaw said:
+1 for Eagle Magneto Service at new Smyrna Beach. Excellent work and quick turnaround at a reasonable price.
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Yep if you live close enough, you can coordinate with him and bring them in with a check, and in an hour or so walk out with fresh 500 hr mags.
 
Any good magneto shops in the Northeast? I have a failed Slick 4301 that needs an inspection and repairs. I've been talking to Aircraft Magneto Service who are well recommended, but their current turnaround time is 4-5 weeks, and they don't currently have a 4301 available for exchange.

(Or anybody got a cheap working 4301 for sale?)
 
Dana said:
Any good magneto shops in the Northeast? I have a failed Slick 4301 that needs an inspection and repairs. I've been talking to Aircraft Magneto Service who are well recommended, but their current turnaround time is 4-5 weeks, and they don't currently have a 4301 available for exchange.
(Or anybody got a cheap working 4301 for sale?)
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I use Aero Accessories in Van Nuys California. They usually turn them around in 2 days, do a great job, good prices, with excellent warranty and support.
 
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