Author Topic: Lucas K2F Magneto No Spark  (Read 3192 times)

Offline Topdad

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Re: Lucas K2F Magneto No Spark
« Reply #15 on: 16.06. 2014 16:01 »
I had that happen to me on the way home from southport ,right on a dark stretch of road the bloody thing cut ,one moment motion the next dead , my mate and pushed her home nearly 5 miles outfit by the way , stayed at his knackered 6am next day pulled the cap of and the ponits fell out pushed home and tightened purred away again me with ten ton of egg all over my mug , stupid or what !! but I was only 16 cheers BobH
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Online beezermacc

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Re: Lucas K2F Magneto No Spark
« Reply #16 on: 20.06. 2014 09:04 »
In defence of mag restorers everywhere! I thought I'd throw in a bit of information about the points centre screw. Obviously it does need to be tight enough to hold the points in place but........  the threaded part of the screw screws into the primary windings connection from the ignition coil. This connection is essentially a square nut insulated from the armature body by a piece of flat fibre material (a bit like the material fibre washers are made from). The square nut is prevented from spinning by its location in a square hole in a plastic insulator tube. If the screw is overtightened two things can happen, 1) the square nut can punch a hole in the fibre insulator and make contact with the armature body, or 2) the square nut can burst the shoulders off the plastic insulator tube. Provided the mag restorer has done a good job with the armature and bearings most other matters are within the scope of most owners. The aforementioned problems are often caused by the plastic insulator tube being manufactured a little too short thereby allowing the nut to travel too far before it tightens, by which time it has guillotined the fibre insulator. The plastic insulator tubes don't seem to be available anywhere so I make my own, to the correct length, and I supply some of the other magneto restorers with them. So, tightening the points centre screw is a slightly more delicate operation than many realise - I have come across plenty of mags where the overtightening of the screw is what has stopped the mag. I can understand why a mag restorer (and I honestly don't think it was me!) might be a bit cautious because, if the screw is overtightened and the fibre insulator is chopped, the mag and the armature have to be dismantled to fix the problem.
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Offline wilko

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Re: Lucas K2F Magneto No Spark
« Reply #17 on: 21.06. 2014 00:44 »
Sounds like a good reason to shorten the screw a pinch for peace  of mind then.

Offline duTch

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Re: Lucas K2F Magneto No Spark
« Reply #18 on: 21.06. 2014 15:01 »

 thanks for the info Beezermacc.. *good3*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online beezermacc

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Re: Lucas K2F Magneto No Spark
« Reply #19 on: 21.06. 2014 23:00 »
Sounds like a good reason to shorten the screw a pinch for peace  of mind then.
Unfortunately this won't make any difference. The screw isn't the problem, it's the fact that the screw draws the nut through the fibre insulator.
Priory Magnetos Ltd - A10 spares, magneto and dynamo refurbs. www.priorymagnetos.co.uk

Offline Terryb

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Re: Lucas K2F Magneto No Spark
« Reply #20 on: 26.06. 2014 20:34 »
Sounds like a periodical check on the centre screw is a must maintenance task. I'll keep a check on mine in future.

2 hours sitting on the Madejski round-about (M4) waiting for the brake down wagon, was not my idea of fun.

Thanks anyway.