M - Electrical System

When the car was rebuilt after the engine bay fire there was obviously a considerable amount of work required.  The remarkable thing though was just how much of the original equipment survived.  The entire engine bay was at first site a charred mess, but as it was stripped down it became apparent that a lot of damage was little more than a heavy carbon coating.  Given the fire was based around the rear carburetor, and that the plenum chamber needed replacing, it is incredible that the blackened coil actually survived.  I cleaned and polished it, tried it and it worked fine, and still is.  The alternator, starter motor and fuse box all survived.  Even the plastic lid to the fuse box responded to polishing.

Wiring loom: once the outer tape was removed the inner wires were largely salvageable so it was repaired and rebound.  If you ever rebind a loom you should use proper loom tape.  The use of sticky black tape is an appalling bodge.  

Fitting new connectors; do you use solder types or crimp types?  Solder appears better, but can still suffer corrosion long term so I stuck to crimping.  Many people hate the red/blue/yellow cable ends, but I have found them OK, provided you pay attention to using the correct size and type for each application.  Also, you must use the correct crimping tool, so I invested in the ratchet tool designed to crimp red, blue and yellow ends with the correct pressure.  Done properly this will create a reliable cold weld and crimps the insulation over the cable securely.  

I also took the opportunity to remove all the horrific additions made by previous owners.  Like the bypassing of the HRW relay in the boot with a really thick wire running all through the car from the switch to the rear window.  This is not only dangerous and unnecessary, it looked dreadful as the wire had been pushed under the vinyl covering on the A pillar.  How could anyone make such a hash of it?  Rant over!

Mods:

Relays:  The two relays in the front offside corner of the engine bay were utterly destroyed so I replaced them with two modern relays that plug into mounting brackets that slot together.  Not only is this much neater, but the relays can be simple unplugged without disturbing all of the connections.

Coil Mounting: Since I had a new plenum chamber I had the opportunity to make a new mounting arrangement for the coil.  The original design relies on aluminium rivnuts pressed into the fibreglass, and we all know that after all these years the bolts will corrode into them and they lose their fixing, resulting in a useless fixing that just turns forever.  My solution is to make a cross shaped bracket that has two fixing nuts welded to.  The long leg of the cross comes to the top of the plenum chamber (just below the grille) and is easy to grip whilst the coil mounting bolts are removed.  A little copperease on the bolts and coil removal will never be a problem again.

Screen washer bottles:  My car always had a bottle mounted on the "box" moulding near the bulkhead on the nearside.  I have never believed that it was original, but it seems exactly the right size.  Mine was destroyed in the fire so I replaced it, the part being a standard Metro item complete with pump.  Very cheap and perfect for the job.  The rear screen wash was originally a plastic bag and a separate pump.  Another design disaster, so I replaced both with a bottle and integral pump.  Mine happens to come from  a Rover P6 and has a pump mounted in the lid and fits in my redesigned boot next to the battery).

Cooling fans: already described in the K - Cooling section

Service Switches: For convenience I installed a switch to turn off the fuel pump and ignition circuit so that I can energise the full electrical system for troubleshooting purposes without overloading the coil or keeping the carbs under fuel pressure.

Electronic Ignition: The S1 car does not have electronic ignition, but the S2 car does.  I fitted a Lumenition system exactly like the S2, and mounted in the same place.  It is excellent and means that I never have to delve into the distributor (see Fuel section for my plate to cover the distributor and prevent fuel dripping into it).

Battery cut-off:  when I had the fire I wanted to kill the electrical system asap and had to find a spanner and fiddle about while the front end burned.  Makes sense to fit a cut-off in the main battery feed.  I used a Switch type as used on all racers because its quick and easy to use.  I tried the Dis-car-nect type and found it to be thoroughly unreliable because it introduced contact resistance which I could never get rid of.  Note that I rebuilt the whole boot and battery area allowing for this switch to be properly mounted.

Charging Socket: The battery box also now has a 12v socket (bulkhead fitting from the local caravan spares shop) which makes it easy to connect a tyre pump from the boot, and to use an Airflow trickle charger.

High Brake Light:  I mounted a long thin High Level brake light to the underside of the boot area roof.  Unobtrusive, but effective.

Rear Fog lamp:  Although I have a S2 rear bumper complete with lights I eventually decided I preferred the design of the S1.  Only thing missing is a rear fog lamp.  I fitted a standard Heller unit in the middle, under the bumper with a dashboard switch and telltale lamp.  I noted that the Peugot 206(?) has a centrally mounted unit so I followed suit, rather than upset the symmetry with an offset fixing.  Lotus did manufacture another rear bumper which has two recesses for rear fog lights.  A better solution and could be made into a standard bumper.  I don't know when these were fitted in production, but they are very rare.

Electronic Hazard Flasher:  I had a poorly performing 9FL Hazard flasher unit, bought another that didn't work and was desperate to fix the problem for the MoT (UK roadworthy test).  I found an old GM unit in my garage designed with three terminals instead of the Lucas 9FL which has two.  Simply wire the old feed wire (B) to (+), the old Green wire (L) to the middle output tag and add a new black earth wire and you have a perfectly timed flash frequency capable of switching 96Watts.  Think I'll do the left/right indicators now!

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