DIRECT EARTH TO STARTER MOTOR

At the recent Technical Evening club night, Phil Whitter suggested that starting would be much easier when having an earth cable directly from the battery to the starter motor, instead of the current having to fight its way through bodywork and chassis.  The very next weekend saw me on the case as the Box is always very sluggish to turn over and starting takes an age, draining the battery to nearly zero.

I had an old pair of jump leads with a chunky-enough inner cable, about 8mm dia., making the whole outer diameter about 10mm, so the black one was donated to the cause.  The only other components needed are two Battery Lead Connectors 10mm Heavy Duty from Halford and/or Motobitz and a couple of 10mm grommets. After a bit of thinking I decided to run the cable from the top set screw holding the starter motor to the crankcase and, to save the new cable sticking up, fitted it vertically downwards between the crankcase and starter motor, under the body, entering at floor pan level at the corner beside the gearbox cover, along the floor on the driver’s side, through a hole into the compartment under the driver’s seat, finishing at the bolt attaching the main earth strap to the body. There is a gap all the way down between the edge of the floor pan and the gearbox cover but I was worried the sharpish edge of the panel may eventually cut through the cable so I opted to drill a hole with a grommet instead.  For the 10mm grommets I needed to drill 13mm holes.  It was also emphasised that one needs to solder-on the ring connectors to the cable but this causes a strategic problem when fitting the cable as the large connectors obviously won’t go through the grommet holes if fitted on the bench – one, yes, but not both.  I decided to solder-on the first connector on the bench away from the engine and fit it to the starter motor without cutting the cable to length, then run the cable through the newly drilled holes and grommets to its destination under the driver’s seat.  One can then finally cut the cable to length in situ withoutfear of it being too short.  To solder-on the final connector, I used a smallish slab of thick, bare metal on which to rest the cable and connector and to protect the surrounding bodywork from the blowtorch flame.

On its first test the engine started first time without any pumping or grinding; but just to do a ‘proper job’ I cleaned the commutator ring by poking my finger, covered in a clean cloth soaked in methylated spirit, through the open bit of the starter motor and spun it over without the ignition on (don’t try this at home!! – use a lollypop stick instead) and cleaned underneath the battery terminals.

It’s made such a difference to trouble-free starting with little expense or time and only a brief visit underneath the car. Thanks for the suggestion, Phil, it really is a great club innit?

David Whetton. DA7C