10 replies to this topic

[Maxmini]

Just need some advice on how to wire up an electric fan with a rad with a temp switch fitted, I know one is earth and one is live but do I need to run a relay inline with a inline fuse and what's the best place to get the power to it i.e the fuse box.

Need to wire up the su fuel pump too at the rear again one earth to the body and power from the fuse box or the ignition also the pump has two breathers do I just run a pipe inside the boot.

Also need to wire in the distributor as it is the electronic ignition can't remember what I have done in the past.

Just need to sort these jobs out to get it up and running thks.

[Dan]

Yup you should use a relay so you can add control options like the fan only running with the ignition.
Run a feed from the starter solenoid to an inline fuse (10 amps blade or 15 amps glass cartridge should do it for most fans used in Minis) and then to the load side of the relay. This can then run the fan which must indeed be earthed. You need to get the polarity of the fan right or it will be running backwards! The control side of the relay needs to be fed from a fused ignition source and earthed through the thermic switch in the rad base. Simple.

A fuel pump with a vent? Odd but this should also be powered through a relay and ideally with an innertia switch in the circuit to prevent small crashes becoming serious fires. It will need to be a whole new circuit, don't try to run it off anything that runs to the boot already. You can take power directly from the battery (using a fuse and a relay) and run a small cable from the front of the car to provide an ignition source to run the relay. The innertia switch should be in the power side of the system so in this instance it would need to be in the boot. That's possibly not the best place for it (it could get knocked about by luggage) but if you want it elsewhere all you need to do is run the power from the solenoid as before and mount the switch where you like before taking the circuit all the way to the back of the car. Got any pictures of the pump?

Electronic ignition just needs 12v to the module. Make sure it's 12v. It needs to be on an ignition circuit obviously and should really be fused.

[Maxmini]

Here we go the breather pipes are located on the top behind the spade terminal and one to the rear of the pump. It said in the instructions to have the breathers run into the car so thay keep clear and dry also where do I get a innertia swith from and the relays any idea on how much thanks Dan.

[Phaeton]

Yup you should use a relay so you can add control options like the fan only running with the ignition.
Run a feed from the starter solenoid to an inline fuse (10 amps blade or 15 amps glass cartridge should do it for most fans used in Minis) and then to the load side of the relay. This can then run the fan which must indeed be earthed. You need to get the polarity of the fan right or it will be running backwards! The control side of the relay needs to be fed from a fused ignition source and earthed through the thermic switch in the rad base. Simple.

I would agree with this other than I would reccomend that you use a constant live instead of a ignition switched source. This means that even after you have switched off the fan may continue to run & prevent 'heat sink'

Alan...

[Xiao_Bin]

I would agree with this other than I would reccomend that you use a constant live instead of a ignition switched source. This means that even after you have switched off the fan may continue to run & prevent 'heat sink'

Alan...

that would be cooling the water in the radiator, so pretty useless unless you have an electric water pump that continues to run together with the fan right?

[Phaeton]

I would agree with this other than I would reccomend that you use a constant live instead of a ignition switched source. This means that even after you have switched off the fan may continue to run & prevent 'heat sink'

Alan...

that would be cooling the water in the radiator, so pretty useless unless you have an electric water pump that continues to run together with the fan right?

Yes, but as it is of the 'sucky' type (assumed) it will be mounted on the outside of the radiator & draw out of the engine bay & pull cool air in the grille & from under the car.

Alan...

[Dan]

the fan may continue to run & prevent 'heat sink'

Assuming you mean heat soak, it's only really an issue on alloy engines. Iron releases the heat it has stored up very slowly compared to aluminium which is a far superior conductor. So it is much less likely for the coolant to boil once the engine is off. It is possible to cool the engine too quickly! You'd be surprised just how soon the fan would turn itself off once the engine has been stopped anyway purely because it is only really cooling the coolant in the rad and the switch is at the coolest part of it. You can always wire it like that if you like but as has been said without the pump running it doesn't cool very much, the thermo syphon effect will draw coolant through the rad but only fairly slowly compared to the pump.

For switches and relays try:
Car Builder Solutions,
Vehicle Wiring Products,
Auto Electric Supplies,
Pole Volt,
Auto Sparks,
or
Holden Vintage and Classic.

Edited by Dan, 07 January 2007 - 12:21 AM.

[Maxmini]

Just spent all day sunday fitting the relays and making brackets but I am pleased with the job. Fuel pump has both breathers joined by a y piece and it runs in the car cabin for clean dry air. The fan was wired in from the solenoid and a 10 amp blade fuse used and the relay was positioned behind the valance fixed with a bracket to the holes in the valance for the horn. The pump relay was fixed to the servo and the power supply was taken from the fuse box at the top job done at last 9 hours of work talk about a labour of love. Just need to check on the wiring of the coil I have yellow and white from the module I take it that goes to the + and the other to the -. The lead that goes to the points does that go to the - or + and the two other leads white and white and black that go to the coil + or - which way round sorry if this sounds abit thick.

Edited by Maxmini, 08 January 2007 - 11:49 PM.

[Dan]

You shouldn't have points anymore if you've gone electronic! Exactly what leads do you have, what's coming out of the module, what out of the wiring harness and stuff like that?

[Maxmini]

Right here we go Dan yellow and white and black and white from the module I take the YW goes to the + on coil and WB to the - . I have a white near the coil and a twin black and white I take it that the white goes to the + on the coil and the twin black and white goes to the - . I have a spare black and white that went to the points is spare now.

[Maxmini]

Can anyone confirm this is the right way to wire the coil and module thks.