Any conceivable reason to only overhaul one mag?

[samiamPA]

Looking through the records of my C-150, I see:

7/99: Tach 4543 "Removed both mags + ck. Condition installed new points in L.H. mag retimed both mags to engine"

10/16: Tach 5043 "C/W Slick SB 2-80C IRAN on left magneto. Replaced coil and reset internal timing and timed to engine."

There is no mention of the right mag in either entry or elsewhere. Unless my A&P can make sense of this, I'm going to have the right mag pulled for IRAN.

 

[kyleb]

Some might prefer not to have both time out at the same time, under the belief that you're less likely to have both mag's fail if you have (at worst) one mag at 500 hours and the other at 250 hours.

 

[biplanebob]

Both mags overhauled at the same time from the same shop, with parts from the same vendor, with the same manufacturing lot number is the same as putting all your eggs in the same basket.

 

[Tantalum]

Came to post the exact sage advice that the two posters above me posted.

Also, why fix it if it ain't broken kind of thing.

 

[ARFlyer]

Our new engine will have one Slick mag and one EIS Mag. The Slick will be the only one to ever be overhauled as there is no overhaul requirements on the EIS Mag.

 

[Dan Thomas]

Both mags overhauled at the same time from the same shop, with parts from the same vendor, with the same manufacturing lot number is the same as putting all your eggs in the same basket.

Gee. I better not ever buy another freshly overhauled engine with two overhauled mags on it.

Honestly. Some of the OWTs around here...

 

[Dan Thomas]

Also, why fix it if it ain't broken kind of thing.

There are way too many guys doing exactly that here. That's why we're constantly hearing of alternator, vacuum pump and magneto failures. Because of the run-it-until-it-breaks philosophy. I'm sure glad the airlines don't operate like that.

 

[GRG55]

Gee. I better not ever buy another freshly overhauled engine with two overhauled mags on it...

Like to live on the edge, don't you.

Looking through the records of my C-150, I see:

7/99: Tach 4543 "Removed both mags + ck. Condition installed new points in L.H. mag retimed both mags to engine"

10/16: Tach 5043 "C/W Slick SB 2-80C IRAN on left magneto. Replaced coil and reset internal timing and timed to engine."

There is no mention of the right mag in either entry or elsewhere. Unless my A&P can make sense of this, I'm going to have the right mag pulled for IRAN.

If there are no entries for the RH mag in over two decades I would do the same.
They are a mechanical device and prone to not giving much if any warning before they quit working.

 

[Radar Contact]

There are way too many guys doing exactly that here. That's why we're constantly hearing of alternator, vacuum pump and magneto failures. Because of the run-it-until-it-breaks philosophy. I'm sure glad the airlines don't operate like that.

Mike Busch is king of on condition and even he says at 500 hr send the mags in for IRAN/overhaul. Last annual sent my perfectly working left engine mags in. This annual doing the same for the right engine. Each at the annual that crosses 500 hours on them.

 

[chemgeek]

Both mags overhauled at the same time from the same shop, with parts from the same vendor, with the same manufacturing lot number is the same as putting all your eggs in the same basket.

Of course, it may not work out that way. My overhauled engine came with two new mags. One, and only one, had a serious SB by S/N last year. Fixed the one and moved on. The S/Ns weren't even close to each other. IRAN is the way to go.

 

[Tom-D]

bucks. $