A short, almost relevant story.....
My father bought a new Ford Cortina, (back in those days), and all went well until it was 4 months old, when it would turn over but very slowly on the starter.
I looked under the bonnet, whilst dad tried the starter, and saw that the Choke-Cable was getting hot and smoking. I realised that all the starter current was going though this cable instead of the Engine Earthing Strap.
I took the Earth Strap off, and found that the paint on the chassis was preventing a good contact... I scraped the paint away, re-fitted the Earth Strap, and we had no further problems for many many years.
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