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MAGNETOS

Over here it's the time of the year when we all start to get round our tractors and make sure that they start after the winter layup.

Every year an odd magneto iginition tractor will refuse to start - "mag gone off" as we say over here.  Often we can cure it by simply giving the points a good cleaning, but sometimes one has to take the magneto off and warm it up in a very low oven.

What's the experience in N. America?  Does the fact that you are frozen stiff all winter protect the magnetos?  Here we have little frost and a very damp climate and this seems to be the problem.

Anyone got bombproof methods of magneto preservation over winter???

John

RE:MAGNETOS

Hi John,

Don't have much experience with the mags (yet)!!  Only have three and they are on the military tractors.  I have not had to do anything special with them (yet) only because they have all been recently rebuilt.

Never heard about putting them in th oven but it would make sense to dry them out a little and to put some heat to their moving parts!

I am sure Dennis or Joe or others can repond better than I!!

GTE

RE:MAGNETOS

This is an interesting thread for discussion,

Yes I can remember hearing the stories not only from my dad but many visitors to shows who remembered working with  tractors of the 30's and 40's era of "how they took the magneto's off their tractor to warm them up in the side oven of the house cooking range" to make them start better, I know here in UK we have a very damp climate and I am sure this has a lot to do with magneto failures.
As John says the common fault is the points and a "greasy like green film" can build up on them over the winter or period of time whilst they are not used, when you come to start them a simple clean of the points and you have a good blue spark again. I often wonder if it is the type of material which the points are made of?? as I have tractors here particularly the styled Red 25 and Pacemaker, one has the Fairbanks Morse and the other is a Bosch flange mounted magneto, both these magneto's have never been touched since 1983 and 1987 respectively, I have never had the covers off them at all and can go to them and they will always start, other Bosch U4 magneto's which on "U" frame tractors have been rebuilt  by professional magneto specialists in the last five years or so will give troubles if not used regularly, why is this??

I often think about Larry Weber and his Dome Valley Museum in Arizona, I know he had to haul his treasures many thousands of miles to their home, but when there they were kept in a superb warm / dry environment, I remember when our containers arrived here after the auction I soon had the tractors running which had not been run for a long time there, the magneto's were hot, only a few weeks later when John got his Orchard GP to Wales it would not start and the magneto was full of Arizona dust which in our climate had gone damp and so another magneto to the repair specialist, and so the saga continues.

There seems to be no answer to this and so many variables, on what should be such a simple thing, I know our rebuilders here are using modern technology for coil winding and replacement etc, but surely there is a simple answer to this problem, we have tried covering them for the winter period, to keep the damp off but still we ask why some and not others just go off. 
Other than heated temperature controlled storage buildings which we cna't justify here it looks like we have not progressed from our previous generations of "putting the magneto in the side oven to bake" 

I look forward to your stories on this subject from across the pond , how is it down under in Australia / New Zealand??

Malcolm.

RE:MAGNETOS

I should perhaps also point out that distributor ignition tractors sometimes "go off" on us over the winter.  A good filing of the points usually always cures them to give an instant start up.

Does anyone know of a way to stop the points getting that insulating surface of whatever it is.  The problem is definitely, in my experience more serious with magneto points than distributor points.  I have been told that they are made of different materials and certainly I have never seen magneto points pitting like distributor poinst do.

Food for thought and hopefully generate some solutions!

John


RE:MAGNETOS

John/Malcolm:

As you know I have many tractors with the Bosch U4 on them, I have to say I have not had much problems with them at all. I have bought many of these mags at swap meets or on ebay and some are dead as a door nail but here is my secret for bringing them back to life.

If you have a dead one on the tractor take a magic marker and mark the coupler with two dots before you take it off the tractor so when you go to putting it back together just line up the dots.
Take the magneto off the tractor and set it on the bench or wheel or wherever you can find a place in your shop big enough to set it then chuck up a 3/4 inch socket into your drill and put a wire in one of the plug wire holes and loop it arround til it is about 1/8th of an inch from any metal part on the magneto.
Back the magneto up about 1/8th of a turn then pull the trigger on the drill quickly and let her rip fast enough so as to not let the magneto trip coggs catch. once it is rolling keep it going all the way wide open on the drill gradually holding the wire next to the magneto once it starts to spark pull it slightly farther away from the magneto.

The farther away you pull the wire the more the coil has to work and the hotter the spark will be, if the magneto is working like it should it should jump a spark up to 3/4 of an inch.
I have taken magnetos that were compleatly dead and brought them back to life by keeping the drill running for 2-5 minutes don't know how it works but I would swear somehow it recharges the magnets by doing this.

Now I know this will not work on all of them as some have bad coils in them but I would say it works about 9 out of 10 times expecially if you are working with a magneto that you know was good a year or two ago.

Just planted corn here last Monday May 14th and it is up two inches today!! The weather here has been awesome!!

Joe
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RE:MAGNETOS

Joe,

Thanks - that sounds like a useful procedure - will try it.  Do you bother filing the points down as well?

Good bit of summer type weather has hit us here too and set to last the week

John

RE:MAGNETOS

Great Bosch Service tool Joe,  I like your work Wallis Cub Junior Widefront workbench!!!!!

We will have to give your method a try in these damper climates, but amazing how some magneto's are affected and others not. Have you ever had to recharge any of your U 4 magnets?

Malcolm.


RE:MAGNETOS

I was talking with an old timer the other night.  He said that for many years he ran a Case magneto ignition tractor from a battery and coil.  If I got the gist of it correctly he just connected the current from the coil to the earth terminal of the magneto.  Said it ran bettter than with a magneto.  BUT HE DID WARN NEVER TO DO THIS WITH A MAGNEOT THAT IS STILL POTENTIALLY USFUL AS IT WILL DESTROY THE MAGNETISM.

More food for thought.

John

RE:MAGNETOS

A retired auto electrician who I was talking with today has a few small tractors and he swears by his method of winter preservation - wrap the magneto tightly in several layers of cling film whilst on the tractor.  But knowing how awkward that stuff is to handle I don't feel inspired to do a lot of tractors in that way!!!!

More MASSEY food for thought!

John

RE:MAGNETOS

And it came back to me whilst I was painting (unusual for me!!) a tractor wheel.  I recall asking my old uncle before he died a few years ago what he did about MH U frames that wouldn't start after the long winter lay off.  His reply was quite abrupt as if I was stupid "well tow the buggers" he said !!!!!!!!!!! "there's always one will start" - and he had 5 of them.

He used to tell me how if a big end bearing started to knock whilst ploughing or whatever he would simply stop the tractor in the furrow, remove the appropriate inspection plate, ondo the big end and remove one or more or shims as required then on his way again.  No time wasting with a MASSEY!!

John