Alternative power-plants and transplants (GTi, Porsche, Subaru, Audi, diesel etc). Discussion and Q&A last answered over 2 years ago.
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only some alternators have a terminal marked 'W' on them
some have a hole but no terminal
as said above this is the take off for the tacho
you also need a diesel tacho as a petrol one will not work correctly .
just check round your local scrappy , dont get anything other than a bosch alternater ,and its usually the reconditioned ones that come with a 'W' terminal
lucas and paris rhome usually have the terminal but are very unreliable units!
if all fails its easy to remove / strip the alternator and run the wire yourself! i can explain if you get stuck. cheers