How long before I take a serious look at the mags?

IRAN 500 hrs means "Inspect and repair as necessary".

Parts are parts and they don't last forever. When One of my engines lets go, I thank the lord J_sus that I have been paying to maintain FOUR mags and tha tI still have bilateral power. When you only have two mags, it's a different matter.
 
Rotor&Wing said:
Again, please show me where the PIC on a flight is required to fill out such a form?



Where did I imply this happened while I was employed by the government?
Click to expand...
Have you been studying at the RoncaChamp school of useful board communication?
 
I've seen mags fail early, and I've seen them make it TBO, with and without maintenance performed on them as recommended by the manufacture. Internal parts could go with no warning as so could the impulse, if so equipped.

TCM/Bendix or Slick, doesn't really matter. Either or could fail when ever they so chose. I've seen the internal plastic parts turn to a butter like consistency when the oil seal failed.

Even if you replace the mags, or get them overhauled, a failure could occur at any point. It is a 50/50 gamble on how long they will make it. Perhaps just get them looked at and the points checked. Save yourself the money as new can be pricy.
 
bbchien said:
IRAN 500 hrs means "Inspect and repair as necessary".

Parts are parts and they don't last forever. When One of my engines lets go, I thank the lord J_sus that I have been paying to maintain FOUR mags and tha tI still have bilateral power. When you only have two mags, it's a different matter.
Click to expand...
The big Letter there is "I" inspect, in accordance with what?

The reference I sited above is the only one I know of to return to service, note the tools and parts required to comply with the "Repair as necessary" portion of the inspection.
 
bbchien said:
IRAN 500 hrs means "Inspect and repair as necessary".

Parts are parts and they don't last forever. When One of my engines lets go, I thank the lord J_sus that I have been paying to maintain FOUR mags and tha tI still have bilateral power. When you only have two mags, it's a different matter.
Click to expand...

I assure you that I quite pleased that I had started with two mags when one of them failed...
 
My mechanic said to just run it until it quits
 
Ted DuPuis said:
So explain to me how my gear failures at ~2000 hours would be seen.



Plastic doesn't talk very loudly. You won't always hear the mag talking before a failure.
Click to expand...


Yep, even if you replace those and dry air pumps @ 500hrs you won't be immune from those instant plastic failures.
 
Last edited:
DavidWhite said:
My mechanic said to just run it until it quits
Click to expand...

Which is fine until it quits on takeoff on a high-DA day with a full load with an obstacle at the end of the runway.

Really, mag inspections are not a big deal for a mechanic used to doing them. Find one that does them and leave the guy that gives you the advice he did. Seems like we have "mechanics" that don't know much anymore.

Dan
 
My mechanic said to just run it until it quits
Click to expand...

Some of us are control freaks and think we can outwit the process by doing preventive mx; its not always true but we try.

I might do the 'run it til it quits' on some of these things but where will I be when it quits? Will I be on a rainy ramp 500mi from home, inadequate tools, no help? Or in Mexico? If I was just a pattern buzzard I might do that, but I would feel silly if I was aog hundreds of miles away, for a stupid 10$ set of burned up points. The other thing is if you look at stuff regularly, you can catch it before it really does a number on itself. A mag situation from my past reminds me: decided to pull a mag and go through it; got lucky - bearings were breaking up, another few hours and the entire mag would have been toast, but I (mostly luck, I agree) caught it before it imploded - was able to save the rotor, housing before it got real bad.
Also if you start running a lot of things til they quit, you will miss out on ancillary finds. Ie open the cowl to check the mags, find a loose exhaust etc, its happened enough.
 
Let'sgoflying! said:
Some of us are control freaks and think we can outwit the process by doing preventive mx; its not always true but we try.

I might do the 'run it til it quits' on some of these things but where will I be when it quits? Will I be on a rainy ramp 500mi from home, inadequate tools, no help? Or in Mexico? If I was just a pattern buzzard I might do that, but I would feel silly if I was aog hundreds of miles away, for a stupid 10$ set of burned up points. The other thing is if you look at stuff regularly, you can catch it before it really does a number on itself. A mag situation from my past reminds me: decided to pull a mag and go through it; got lucky - bearings were breaking up, another few hours and the entire mag would have been toast, but I (mostly luck, I agree) caught it before it imploded - was able to save the rotor, housing before it got real bad.
Also if you start running a lot of things til they quit, you will miss out on ancillary finds. Ie open the cowl to check the mags, find a loose exhaust etc, its happened enough.
Click to expand...

Dave this is a very good point. I think we will try to get them replaced before I do any more big trips.
 
I open them up every year, I don't care which brand that they are or what aircraft it is. I can't believe what I've found during an annual on mags that showed no operating issues. On most engines they are easy to check. At my MMOPA seminars I always talk about how it's cheaper to replace the mags every year than it is to get 4 to 5 people home Sun. afternoon on an airline. I believe if the shop wont open them at annual, they should be replaced or overhauled.

It drives me crazy that this is such a big issue for a normally simple annual item. Also the mags on a Mirage are a lot of work to remove, but it needs to be done.
 
kmead said:
I open them up every year,
Click to expand...
What do you use as reference to return them to service IAW 43.9

(a) Maintenance record entries. Except as provided in paragraphs (b) and (c) of this section, each person who maintains, performs preventive maintenance, rebuilds, or alters an aircraft, airframe, aircraft engine, propeller, appliance, or component part shall make an entry in the maintenance record of that equipment containing the following information:

(1) A description (or reference to data acceptable to the Administrator) of work performed.

(2) The date of completion of the work performed.

(3) The name of the person performing the work if other than the person specified in paragraph (a)(4) of this section.
 
Last edited:
http://www.tcmlink.com/pdf2/SB643B.pdf

Aren't we glad Service bulletins aren't mandatory?

C. In addition to the requirements listed above, magnetos must be overhauled or replaced at the expiration of five years since the date of original manufacture or last overhaul, or four years since the date the magneto was placed in service, whichever occurs first, without regard to accumulated operating hours. Also at this time all related components, including the High Tension Ignition Harness, Starting Vibrator Assembly and Ignition Switch Assembly, must be inspected for airworthiness in accordance with the procedures contained in the latest revision of their respective Service Support Manual.

 
There's also the factor of replacing a known good part with new and unproven. The balance to that though is that you have a known good for a spare that you can keep in the plane in case you experience infant mortality and then sending in the core.
 
Yep, I still have my old slicks, I plan on carting them around on longer trips. Beats getting stranded.
 
I perform the 500 hour Slick mag inspection on my aircraft per the OH manual (section 3.3). I routinely replace the points and cam, other parts as needed. This is not an overhaul. There is usually not a need to replace the mag, unless multiple expensive parts are needed for the IRAN (the cost can approach or exceed the price of a new mag). Some PMA parts are available at a lower price, and we have had good service life from them.

"Fly until it breaks" is foolish dis-economy. My planes can be IRANed or repaired in my hangar at a small fraction of the cost of a breakdown while traveling. I IRAN the accessories on my aircraft in rotation (mags, starter, alternator, electric fuel pump, flap motor, gear motor, etc) of one or two items per year. Since adopting this approach my AOG problems have disappeared.
 
dmac5356 said:
I perform the 500 hour Slick mag inspection on my aircraft per the OH manual (section 3.3)....Some PMA parts are available at a lower price, and we have had good service life from them.
Click to expand...

Who makes PMA stuff for the Slicks? It would be nice to buy the distributor assembly for something less than the nearly $300 I paid some time back.

Dan
 
Dan Thomas said:
Who makes PMA stuff for the Slicks? It would be nice to buy the distributor assembly for something less than the nearly $300 I paid some time back.

Dan
Click to expand...

Unison is the only one I know of.
 
dmac5356 said:
I perform the 500 hour Slick mag inspection on my aircraft per the OH manual (section 3.3). I routinely replace the points and cam, other parts as needed. This is not an overhaul. There is usually not a need to replace the mag, unless multiple expensive parts are needed for the IRAN (the cost can approach or exceed the price of a new mag). Some PMA parts are available at a lower price, and we have had good service life from them.
Click to expand...

Your ticket, your liability, because picking and choosing which part of the manual you choose to follow will not stand the scrutiny of FSDO, or your insurance company.
 
Dan Thomas said:
Who makes PMA stuff for the Slicks? It would be nice to buy the distributor assembly for something less than the nearly $300 I paid some time back.
Click to expand...

Champion is the Slick OEM now, with prices even higher than before. PMA parts for Slicks are made by Tempest/Aero Accesories. But not all parts are available (such as the distributor block), unfortunately.


Tom-D said:
Your ticket, your liability, because picking and choosing which part of the manual you choose to follow will not stand the scrutiny of FSDO, or your insurance company.
Click to expand...

We follow the Slick manual section 3.3 (defines the procedures for the 500 hr inspection) in it's entirety. No "picking and choosing". Since the Slick OH manual specifically calls for 500 hour inspections, mechanics should be more concerned about the liability of NOT performing them. If they sign off an annual with 501 hours on a Slick mag without the inspection, the mag fails, and the plane crashes into a school bus... you will be sued and the jury will not have sympathy.

We work the FAA guys frequently on STC's, field approvals, etc. They have inspected our log books occasionally (especially when our flight school was flying 1,000 hrs/mo). Never had any problems with our maintenance.
 
Last edited:
dmac5356 said:
Champion is the Slick OEM now,

Actually Unison is, and they are owned by GE.



We follow the Slick manual section 3.3 (defines the procedures for the 500 hr inspection) in it's entirety. No "picking and choosing". Since the Slick OH manual specifically calls for 500 hour inspections, mechanics should be more concerned about the liability of NOT performing them. If they sign off an annual with 501 hours on a Slick mag without the inspection, the mag fails, and the plane crashes into a school bus... you will be sued and the jury will not have sympathy.

We work the FAA guys frequently on STC's, field approvals, etc. They have inspected our log books occasionally (especially when our flight school was flying 1,000 hrs/mo). Never had any problems with our maintenance.
Click to expand...

What is your typical verbiage entered in the maintenance records?
 
DavidWhite said:
Dave this is a very good point. I think we will try to get them replaced before I do any more big trips.
Click to expand...

I have started carrying around a spare good mag and starter with me. In your case, an alternator might not be a bad idea, either.
 
Ted DuPuis said:
I have started carrying around a spare good mag and starter with me. In your case, an alternator might not be a bad idea, either.
Click to expand...

haha, I am with you Ted, including a vac pump, spark plug, tire, alt belt, etc etc. Now have a spare power pac too, looking for an alternator.
 
I understand that Transdigm Group Inc, owner of Champion, purchased the Slick mag line from Unison in Sept. 2008. Has something changed again?

Tom-D said:
What is your typical verbiage entered in the maintenance records?
Click to expand...

Performed 500 hour inspection per Slick manual L-1363F Magneto Maintenance and Overhaul Manual (and replaced parts, if any).
 
Last edited:
Let'sgoflying! said:
haha, I am with you Ted, including a vac pump, spark plug, tire, alt belt, etc etc. Now have a spare power pac too, looking for an alternator.
Click to expand...

Spare parts are a wonderful thing... except they are heavy. I keep the heavy spares in the hangar, and if needed they can be sent overnight in a pinch. But with regular IRAN's I have not had an accessory fail in years.

In the old days there were mechanics at almost every airport, and they had some spares. Now we need to be more self-sufficient.
 
dmac5356 said:
I keep the heavy spares in the hangar, and if needed they can be sent overnight in a pinch. .
Click to expand...

Rather than putting them in the hangar I would put them in labeled boxes with pre-filled airbills and keep them at a business location, either your own or a friends. That way, a phonecall at 4:30 can get it on the 5pm fedex truck without the need of someone heading to the airport first.
 
Last edited:
Last edited:
Let'sgoflying! said:
haha, I am with you Ted, including a vac pump, spark plug, tire, alt belt, etc etc. Now have a spare power pac too, looking for an alternator.
Click to expand...

Well, I keep the spare vacuum pump, alternator belt, etc. conveniently on the other engine. ;)

The tire isn't a bad idea, although since the mains and nose are different that probably won't work. I should add a spark plug to the list.

dmac5356 said:
Spare parts are a wonderful thing... except they are heavy. I keep the heavy spares in the hangar, and if needed they can be sent overnight in a pinch. But with regular IRAN's I have not had an accessory fail in years.
Click to expand...

I am currently at CYMT, and this isn't the most remote place I go.

Overnight? Ha. The only way something's getting here overnight is if a friend of mine flies it up here.
 
weilke said:
Rather than putting them in the hangar I would put them in labeled boxes with pre-filled airbills and keep them at a business location, either your own or a friends. That way, a phonecall at 4:30 can get it on the 5pm fedex truck without the need of someone heading to the airport first.
Click to expand...

Good plan... although my hangar is my place of business!
 
If you were in the deepest wilderness and your left mag showed a 350 RPM drop over the right mag at 50 RPM would you fly it?

It runs smooth on both, develops good horse power, and shows the proper RPM at full throttle.

Would you panic and bring the A&P and a new mag?
 
Tom-D said:
If you were in the deepest wilderness and your left mag showed a 350 RPM drop over the right mag at 50 RPM would you fly it?

It runs smooth on both, develops good horse power, and shows the proper RPM at full throttle.

Would you panic and bring the A&P and a new mag?
Click to expand...

How far over what territory? Good territory, short flight; I'm gone. If not I may shut down and pull out the tool box and check the points (if it wasn't a cylinder miss that caused the drop, then I'd look at the plugs if I couldn't get it to clear during the run up.) If the points were good and timing correct (you know how to check timing with a cigarette cellophane?;)), I'm gone. If I didn't feel like getting dirty, I'd be gone anyway.
 
Last edited:
Henning said:
How far over what territory? Good territory, short flight; I'm gone. If not I may shut down and pull out the tool box and check the points (if it wasn't a cylinder miss that caused the drop, then I'd look at the plugs if I couldn't get it to clear during the run up.) If the points were good and timing correct (you know how to check timing with a cigarette cellophane?;)), I'm gone. If I didn't feel like getting dirty, I'd be gone anyway.
Click to expand...

Yeah I know, you'd cut down a tree and build your self a new engine using your jack knife, and 2 rocks.
 
Tom-D said:
Yeah I know, you'd cut down a tree and build your self a new engine using your jack knife, and 2 rocks.
Click to expand...

You at least need a leatherman for that.:D

John
 
You must log in or register to reply here.
Back
Top