Mechanical

Mechanical

Most of the magnetos and dynamos we have in for repair are old - at least 40 or 50 years, some are now 100 years old! Over recent years there has been an increasing number of 'cottage industries' re-manufacturing parts for some of the more common units but what if it is from an obscure manufacturer?

This is where our well-equipped workshops come into use. We have turning, milling, grinding and drilling equipment as well as sheet metal fabrication and welding facilities. If we cannot source a needed part, we can often repair the original or perhaps modify a similar part from another model/manufacturer. If all else fails, we can usually re-manufacture a new part ourselves - and if we can't, chances are we know someone else who can!
 
The following pictures show some of the jobs carried out in our workshops: 

A rotor arm bearing and retainer from a Simms C4 magneto dating from the 1920s. Worn broken parts shown together with the re-manufactured replacements.

These were straightforward machining jobs but sometimes we have to start with a casting such as with these bases for Dixie magnetos. The red part is the pattern manufactured for us by a time-served pattern maker.

A fractured die-cast dynamo brush holder from a 1927 Lucas MDV magdyno together with the re-manufactured replacement. 

1920s Splitdorf DU5 generator changed from 3 to 2 brush operation, mechanical cutout replaced with electronic voltage regulator fitted hidden away inside the end cap and a new terminal post manufactured.

Switch box for 1920 Henderson motorcycle manufactured from supplied drawing.

A repaired distributor cap and sundry other parts manufactured from scratch for a Bosch RJMU 4 magdyno overhaul.

A vent for a Lucas GA4 distributor cap. The original had a broken gauze - rather than try to repair it, we decided it would be easier to make a complete new vent.

A common problem - a broken slip ring, this time from a Simms C4. See how we repaired it here

The top points plate from a Splitdorf NS2 was made by a previous 'repairer'. Apart from being too flimsy there was no means of adjusting the gap...... We made the lower points plate to the same pattern as the original.

A Lucas E3HB-7 dynamo was missing the points assembly. After a long search, we found the two parts on the right but had to manufacture the assembly on the left from scratch.

A replacement pickup for a UH magneto - always easier to make when the old one is there to copy!

Straightening this location clip for the rotor arm on a Voltex L4 magneto resulted in a piece falling off....... We made a replacement - shown on the right.

Some of the fine gauze on this Peugeot dynamo was torn or missing altogether. The cooling fan inside the dynamo is likely to draw any petrol vapour into the dynamo where it would be ignited by any sparks at the brushes. The fine gauze prevents any resulting flames from getting back outside the dynamo - the same principle as the Davy miner's lamp. The cover on the left shows the problem, the one on the right has already been corrected

The armature end on this Berling magneto had a loose bearing, the taper was very poor, the thread was stripped, the keyway had been stretched and, to cap it all, the steel shaft was loose in the brass end! The easiest option was to make a new end in non-magnetic stainless steel.

This dynamo for a 1930 Harley Davidson was missing several parts when sent to us to overhaul. With the  customer's help, we managed to find and/or manufacture everything except the end cap. The customer was able to supply the one shown which was from a later model - slightly too big on the diameter and the fixing holes were at a bigger pitch. We got round the problem by making an aluminium adaptor ring to sort out the different diameters and an oval adaptor plate to provide fixings for the two screws. The dynamo could then be fitted and used but the good thing is that, as and when the correct cap is found, the adaptors can be easily removed.

This anchor for an advance and retard cable adjuster was in very poor condition. A helicoil repair was done to the magneto body and a new anchor manufactured using the original as a pattern.

There are some more detailed examples of our work in the Workshop section


All the above jobs were done as 'one-offs'. They give an indication of what can be done but they do take time and that has to be reflected in the charges we make. Yes, we could just stick to the common everyday magnetos and dynamos where replacement parts are readily available - but that would be boring! We do like a challenge - some of them can be seen here
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