Eiseman Magnetos

[MikeB]

What causes a magneto to 'go bad' just sitting around? A friend of mine needed a magneto for his A65 and I gave him one of the spares that was on my old engine. Had been sitting on the shelf for a couple of years, but was working fine when I replaced the engine. Anyway, has a good impulse snap, but no spark. Points appeared Ok and no visable oil into the mag. Eiseman mag, by the way which I had zero trouble with when they were on my plane. My new engine came with a Slick kit.

It's a club plane and they will probably go with a couple of new Slicks at this point, but just wondering if anyone else has had the same experience.

Thanks,

Mike

[Mnflyer]

Hi Mike my guess is there is corrosion on the points even though they look good there is a film on them and won't fire the mag. Take a piece of plain white paper and slip between the points and slip it back and forth a couple of time and then try it. Some times a coil will go bad sitting on the shelf, the coils in some of these mags are many many years old.

[big chief 48]

could also be a bad condenser. I've rebuilt lots of eisemans and always replace the condensers because after sitting a long time they seems to get weak. Maybe just my imagination

[kevin mielke]

If you use the paper trick, remember to open the points before you pull the paper all the way out. Otherwise small paper fibers are left behind and they burn pits into points. Just a trick to put in your bag.

[MikeB]

Probably should have tried it for spark before he stuck it on, but we'll look at it later this week (putting new siding on the shop with wife helping right now . For all the bad press the Eiseman mags seem to get, I've had good luck with them. My AI describes them as ##****### , but they do seem to run and run. I think the old Eiseman that he was replacing must have run over 2000 hours according to the logs.

Let you know what we figure out.

Mike

[Ron Babos]

They seem to be good bang for the buck Mike. As mentioned, I look at oxide on the points or a dry condenser. Nail file will cure one problem.
Ron

[big chief 48]

I am a fan of those old eisemans for one reason- they are servecable. A good oops story that turned out well goes like this. Had a mag go bad, and after isolating the bad mag, I took it apart and with the help of an old time A&P we rebuilt it from the bearings on up. (The bearings were actually gone.) put mag back on plane and guess what, I isolated the wrong mag!!! So the one without bearings was the one that was working. Very close to a rare double failure. Rebuilt other one now that I was an eiseman expert and have not had trouble in over 600 hrs.

[Jody Wittmeyer]

I swear by the old Eisemanns. Bullet proof and easy to repair. Of course I have good luck with Strombergs too.

[drjeff]

Last weekend, I was cleaning up in the garage and I picked up a mag that still had the wiring harness attached. I started to look for something and not thinking, spun the gear on the mag. It only took a second to realize that the other end of the leads were against my bare leg!

Needless to say, I didn't spin it a second time! I can't wait till my young nephews come over to uncle Jeff's house!!!!

[Nathan K. Hammond]

There use to be a high school science teacher that kept a magneto laying around the class room. When the session on electricity would start, he'd have everyone hold hands and a lead. The teacher would start cranking the mag as fast as possible until somone let go and sat down. That went on until there was only 1 kid standing. Some how that was a lesson?!?!

Ah the good ol days.....

nkh