cat 22 magneto

Hi Leon, I recently had a long chat to a retired Electrical Engineer here in Australia who spent his entire life building, installing, and repairing gensets for one of the most well known companies in rural Australia, he is in his 80's and now battling terminal prostate cancer. I asked him about "remagnetising" magnets on old Caterpillar magnetos because I hear it often mentioned, and his opinion was it would be very unusual for that process to be required on most old units UNLESS the magneto had been dropped repeatedly, or hit sharply with a heavy object, or, been left sitting on top, or in close proximity to an an electric current producing machine like an Arc welder or generator. It seems there is very little magnetic force required to produce a reliable spark.

I really enjoyed talking to this gentleman as I know very little about repairing old magnetos, he said around 95% of magneto problems are usually repaired by cleaning the points and all the electrical connections within the magneto, if that doesn't work then replace the condensor, if that doesn't work then it is most likely in need of rewinding if it is an old unit such as the one out of a 22 like yours, here in Australia that now costs about $US180-$US200 to rewind. Of course there can be other oddball problems to drive you nuts with these old magnetos, and if you have a full head of hair right now I'd get a family portrait taken ASAP before you start losing it.

Right now if I was in your shoes I'd clean all the connections within that magneto if you are confident your points are clean and adjusted properly, if that fails contact your local Cat Dealer or Florin Tractor for a genuine condensor, or a local magneto shop for an alternative. Most old magnetos benefit from a good clean out and relube of the bearings in any case, even new bearings on the old gas Cat magnetos that have done a lot of hours, I think the bearings on my 2 Ton Eisemann magneto were about $US25 around 5 years ago. Just remember that electricity is a lazy beast and will always take the path of least resistance to Earth.

Good luck.
regards
Mike

Thank you Mike. I took it off the tractor today and am in the process of cleaning it. It is actually very clean inside. I also have located a fellow locally that recently acquired a factory Bosch mag charger, so we will see what we can do to get it to spark. Can also test the condenser. The magnet sure doesn't seem to be very strong and they must have supplied the mag chargers for a reason?? Thanks very much for your help. Leon

Hi Leon,
the magnets in the standard large Eisemann type maggie are actually part of the rotor shaft assembly in the core of the maggie and therefore would not transfer a lot of magnetism to the outside of the main body.
Good info given by others re-clean points, connections and a good condenser. A failed condeser will usually allow one fair spark until the coil saturates and then needs time to discharge and then you may see another one fair spark and so on.
If you can feel a fair magnetic buildup resistance to turning the rotor shaft, with the impulse machanism disabled, then the magnets are likely OK.
Cheers,
Eddie B.

just an update to my project 22 which took a back seat to winter holidays down south. I finally got spark from the mag by replacing the coil which was bad and by recharging the magnet. I did manage to get it to fire but not catch. Ended up push starting it a couple days ago with the help of my son in law and daughter. The engine runs well with no blue smoke. Not bad for not running for the last fifty years. Ran it for about a half hour with good oil pressure and no overheating as well and no leaks from the rad. Next thing to tackle will be the steering clutches and brake system. None of that is functioning. Clutch feels good with some throughout bearing noise which got quieter with more use. There was no final drive gear oil in the left side and the right had mostly water in it. Will have to decide where I go from here with it. Lots of fun so far. Leon[attachment=8957]IMG_2455.jpg[/attachment][attachment=8958]IMG_2467.jpg[/attachment][attachment=8959]IMG_2457.jpg[/attachment]