The V8 Owners Forum -

I I have a TR7 V8 (Rover SD1) from 1980 which has a Kenlowe electric fan fitted and this is key to keeping it cool in slow traffic. The fan takes power through the main wiring loom under the dash and the wires get rather hot which concerns me as TR wiring looms are always a bit dodgy. I plan to fit a relay so the fan takes power directly but all the wiring diagrams show the connection being made directly to the battery, which is in the boot so quite some distance away. The alternator is very close to the fan controller so could I connect to the output side of this ?? The starter motor is also quite some distance away and under the car but could be another option ?? Any advice or thoughts much appreciate as am trying to get the car in reliable order for a trip next weekend.

thanks Jonathan

Alternator is a sensible choice, after all when the engine is running it provides all the power.

Wire and fuse accordingly, with any fuses as close to power source as is practical.

Many thanks for the quick reply to the posting, and using the alternator does make it a lot easier as located next to the fan controller. Can you advise on the relay spec or type which I need as there seem to numerous different formats and I am new to this.

I would go with a 'normal' automotive relay. Ideally get one with a holder / socket.

Have a browse of Car Builder Solutions or Vehicle Wiring Products websites for inspiration!

Chris.

Do fit a fuse close to where you pickup the high power feed from the alternator output wire.
Does the TR use other relays? Most common car ones are 5 pin single pole double through (changeover) which can be wired as a simple on off too. If you already have that type on the car makes sense to use the same for your fan too as it can be wired as a simple on/off.

This shows a SPDT relay wired as a simple on/off.