OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk Wipac Magister Condenser Discharge Ignition System

Complete system in the flesh.....sealed unit has been stripped of components.
So it can be done...what remains to be seen,is whether the parts can be sourced and then fitted to its original housing. I am however optimistic it can be done.

Nice pictures, Blue. If you test the original components, you should easily find which ones work and which ones don't. The most likely component to fail, is the capacitor (condenser). I'm guessing that you will put it back together with some more convenient type of protective material than the original - maybe some RTV silicone adhesive?

Yes possibly,but I do have easy flow epoxy and might is it just to secure the parts as silastic will be more destructive to the unit if removal is necessary. Ill make a cover plate and seal that.
Agreed on the Condenser/capacitor Grumps as it had a weak spark before I stripped It.
did everything to boost it...new lead points checked and rechecked and all connectiins redone....but barely any change.

One thing im curious about is the switch and BM strip. I always assumed it eas a cut out and closed on overheating....but in a prior post it says its a switch,which on dismantking proves this...BUT... I only got spark when the strip was not touching the switch contact.

Anyways lets see what happens as we go along

Thanks Again Gadge and Grumps for your help and input

Cheers

I think that is an ordinary kill switch, Blue. Hence it shorts out the ignition system when it makes contact. Grant (willingworker) was still running a Magister on his usual mower a few months ago, and using that copper strip as the kill switch, as he had always done.

You might try checking continuity and earth leakage of the transformer (HT coil). Use a megger for the earth leakage - they test at around 300 Volts, which is much lower than the service voltage, but makes more sense than using an ordinary DMM as a test on a High Tension coil.

Yes mate that was my understanding either a kill switch or overheating strip like a bi metal strip....But it was actually willing worker in a prior thread who said it was an ignition switch. So I took that to mean the strip was permantly contacted and opened if the thing overheated.... But both mine do not make contact which I knew was how it worked.....All good,pays to just make sure...

I would think that the transformer coil would be the difficult component to replace. Mainly due to its small size; its electrical characteristics aren't too unusual.

It may be possible to get a transformer coil rewound by a magneto repair specialist, but I wouldn't expect that to be cheap. There are only a few of these specialists about, and some also rewind other very small coils, such as the pulse generator and trigger units used in more modern motorcycle ignitions.

As grumpy says, the capacitors of that era were very failure-prone, but it's easy to find a far superior modern equivalent. Same for the rectifier diode, and I'm a bit suspicious about the reliability of the original type. If it is indeed a selenium type [as stated in that 'The Motor Cycle' article earlier in this thread], those weren't known for their durability.

I would be very surprised if that cutout switch is a bimetallic strip - plain hard brass would be much more likely.

Agreed Gadge...Ive found a few equivalent caps and diodes. But yeah the coil may be the hard bit,but ive an electrical engineer mate who designs lighting alarm and power systems,so ive got a foot in the door for parts....Yes the strip is plain brass and doesnt give like a bms...

Anyways im happy to give it a go,if all fails then ive got my spare on a runner but didnt want to swap it over to my display 35 as it will be wasted.

Hi all,

I've just posted some Supa-Swift info. in the History Forums.
I have a question ...

The Villiers Torque-Major Deluxe 140 engine used a Magister ignition with cut-out switch.
I was wondering whether this is of any help here?

Link to Supa-Swift HERE.
Link to Villiers 140 HERE.

All very interesting.
------------------------------------
JACK.

Gadge has obtained a Turner serviceman's instruction sheet for testing the Magister unit. Here is a scan of it:



Thanks Gadge, that gives us some information on the components themselves.

I should say that heat is the only practicable means of 'depotting', given that the potting compound is known [from 'The Motor Cycle' article above] to be an early Araldite epoxy.

There are only one or two solvents that will work on cured epoxy resins, and they are nasty enough to require a fume cupboard. Even then, it takes some time. Not sure if they'd affect the phenol-formaldehyde resin [Bakelite] casing as well, either.

For re-potting, there are any number of different non-corrosive 'electronic potting compounds' available these days. Check the RS Components or Element14 websites for examples.

I feel that there has been adequate time for comment since the last post here, so I'm locking this thread once more.

As always, it can be re-opened by requesting a Moderator to do so.