Defender Starting Woes ...

[SavingTheDefender]

So on the odd occasion The Defender fails to proceed. A single click from under the bonnet and the dashboard lights up.

To date I've replaced the starter motor, the green start relay and the ignition switch. Clearly I am missing something... But what?

[Michael2]

Poor Earth - run a cable from a starter motor bolt to the chassis.
Poor Cable - connection - check the bolt connection to the starter and make sure the bolt is not loose, check the cable connection at the battery.
Poor Solenoid connection - check the crimp on the solenoid wire is tight and clean.
Poor Battery - is your battery old / damaged.
If you tap the starter motor and it starts, then it's the solenoid internals.

[wrinklearthur]

Pull one of the heavy cables off at a time and refresh the solder inside the crimped on lugs, if there is a fine crack there that can not be seen then the fresh solder will fix that.
Make sure the two surfaces, the lug and the metal the lug sits on is bright shiny metal, then after it's tight, squirt some rust stop type paint to tidy up the job and this will stop moisture getting in to cause any more corrosion problems.
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