Electricity Troubles

[diggerdog36]

Ive changed the engine in my 90 to a 200tdi, started fine, then a week later.....nothing, just a clicking sound from a relay in the cab.  Ive got 12v at the large diameter cable at the starter, the small spade plug has 0.03v, when the key is turned, I get 0.12v at the small spade terminal????

Got me baffled, it worked fine last week, its a brand new Optima Battery???

[tonycougar]

The large cable will have 12V on because its connected direct to the battery.
If by 0.12V you mean 12V at small terminal (ie roughly battery voltage) when key is turned, then I would suspect a main earth problem.
Try connecting a jump lead from the battery earth direct to the starter body then try to start it. If it works then there is your problem, go around checking your main earth leads.

[diggerdog36]

NO, I mean 0.12v, it was 0.03v without the key turned, then it went upto 0.12v with the key turned to the start position!!!!  I shorted the large cable to the spade and it started, so the problem lies in the ignition barrel/relay line.

[tonycougar]

OK happy hunting.

By the way I've just noticed you are only down the road from me.