I last ran a Magneto engine in a Chummy when I was student - a long time ago. Then it was a case of using anything that provided a spark. I am now in the throes of rebuilding a mag engine to fit in a 27 Chummy that has been running with a 29 coil engine. I now need to choose a magneto to give to a specialist for an overhaul (rewinding coils, remagnetising, new condenser etc, etc)and hopefully that should see me sorted with a reliable unit for road use. I have a Blic A4R or an ML RG4 to choose from. Is it really only a case of personal preference or is there such a thing as one make is generally accepted as being rated the best. When I talked to the mag specialist he said that ML's were known to be a cheaper make. Would thus welcome comments from the Forum.

Correction - the ML magneto is an RF4.

In my opinion the ML RF4 is the one to go for as its unbelievable simple and as a consequence can easily be restored at home. D.H.Day in Wroughton near Swindon can rewind the coil for around £70 and remagnetize for a tenner. You can have it apart in 15 minutes. There is a good site on the net that sells all of the spares including the distributor cap that I think was around £80. will try to find the site and get back later.

This is the site for RF4 spares http://www.magneto.co.uk/acatalog/Index.html

ML every time

Well, that's unanimous, but will you want to carry a spare mag? In which case the answer is both!

Regards, Stuart

Buy a coil conversion from Willie McKenzie and cast your cares aside.

Why do that? If you have an old ML that has the coil burnt out, simply connect a normal coil through the breather gauze and hide it out of sight. I have one converted like this under the rear cushion just in case.

When my grandfather bought his seven in 1927 it came with a BLIC magneto. This failed after about a year or so and he replaced it with a ML RF4. This proved totally reliable and ran until 1956 when he gave up driving.

I've run the same car from 1960 with the same mag, and apart from a rewind about 5 years ago because the original shellac insulation was beginning to break down it has never given any trouble whatsoever. If you understand what shellac is, the surprise is that it takes so long to decompose. Modern insulation materials can be expected to last much longer.

Forget about coil conversions. A decent mag. is more reliable.

What ignition systems do piston aircraft engines have? Would they rely on anything at all suspect?

MAGS ARE WONDERFUL ! ! !

Martin

I am in total agreement there is no reason why a mag should not give reliable service year after year,in all the years of driving sevens have never had one pack up on me.And you also don't require a battery.MLs were fitted to S/C EAs because they have fixed windings and cannot throw them even at the higher revs.I think that the myth that mags are unreliable grew up in the 50s when it wasn't economic
to spend money to rebuild a damp 25 year old mag.

I also agree that the Mag has had a bad press over the years,Mine has been on the car for 11 years without missing a beat,and I hope it will go on for another 11 If I`m still about.

I do wish that my own experiences with magnetos had been so positive. The last straw for me occured when the one on my own csr threw all the shallac in the Pyrenees,the spare didn,t work[despite an expensive rebuild few weeks earlier]and I was forced to Jury rig a coil coversiion on the mountainside. This proved enormously successful,and I have never looked back. THe fuel consumption increased by 10% and

the car starts first pop up every time. Just as a matter of interest,I wonder why Austins changed to coil ignition in 1928 if it was felt that the magneto system was so reliable?

That ones easy. At the time Austin were in a price war with Morris (wash you mouth out !) and the coil system was cheaper.

Martin

I tend to agree with Ian - don't I always? (even on foxhunting!). Admittedly my experiences are only with BLICs on Pramhoods, but I've had no end of troubles. In the past I've put it down to the lack of expertise these days to do a proper job when full-reconditioning, but there are enough contemporary, when-new, accounts of magneto problems to worry one. Not sure about UK but an Automotive Electrical apprentice in Oz these days has no tuition on repairing mags, so future not good. Cheers, Bill

Bill, Can`t get the workers these day`s can you!
It` horse`s for course`s I use both!

I didn't think that modern rewinds used shellac anymore. Might be wrong but I thought that a better epoxy was used nowdays.

Charles

The original one threw the shellac. The new repair didnt work at all However all this took place in 1983,so please don't accuse me of holding a grudge.

I have used professionally rebuilt BLICs for the past 35 years and have had very little trouble with them. The main problem has been that the little bit of felt which filters the oil from the spring-loaded ball on the top of the case gets clogged, and the large gear spindle dries out causing a screaming noise.

The magneto seems so easy when contrasted with the problems that friends have with their coil ignition systems. Is it the coil? the distributor cap? the condensor? the rotor arm? the points? the wiring? the battery? the ignition switch perhaps? I know, let's swap all these individual bits to see if that cures the problem. And oh dear, the little red light glows all the time. With all these different parts scattered around the car, give me a mag (and a spare!) any time...

David

I'm just back from a long weekend in the West Highlands of Scotland searching for magnetoes for Austin Sevens. Thanks to everyone for their responses thoughts and suggestions. Interesting comments and support for both Blic and ML. I noted that there was no comment such as find a Bosch (or Lucas or BTH ) have it reconditioned and have no more worries. I did run a Bosch magneto in my 28 Special in my youth and one day decided to give it a clean and paint. After the dismantling cleaning and painting it never again produced a spark but it did look good.