1909 MERCEDES

AERO ENGINE BUILD

Part 23/23 by Steve Gosling

...continued


A trial assembly and looking good. I fitted the brass screw contacts with the nuts on the back. Connecting the wires without anything touching or shorting is going to be a challenge!

A quick fit to the engine and it looked OK although some more adjustment was needed to make it all sit in the right place.
I realized that Hall effect sensors are sensitive to the polarity of the activating magnets so it is critical which side faces the sensor. A pal of mine is a retired telecoms engineer and he kindly set up the switch with an oscilloscope so that we could hold a magnet nearby and see which face worked. We started off by putting some tape on one face so that we could tell the difference! I then wrote down the result and came home to push the magnets into place in the rotor.
Then onto the terminals. I simply filed up a fork which could be pushed on to the plug. The challenge here was handling them and seeing them!
I bent the cable ends up with a piece of steel in the drill chuck and the brass resting on the top of the machine vice.
I cut some silicone rubber insulated meter lead, tinned the ends and then secured them inside the distributor cap taking great care to keep them as far apart as possible.
soldered the terminals.
Then a bit of felt on the underside and some Brasso on the shiny bits and it is ready to show.
 
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