Radiator Fan not working

[Newoldbiker 45]

So I removed my radiator last year as the paint was flaking.  I fixed that and did the valves at the same time.  Since I've put it back together the fan hasn't switched on.  I used to commute into central London and in weather like we've just had when I ended the ride the fan was always working.

 

I'm thinking one of the wires have come off in the connectors at the back for when you remove the radiator?

 

I'm planning to remove it again and look at the connections checking they are still solid.

 

Any other suggestions/advice would be happily received :-)

 

Thanks as ever

[kayz1 2,928]

Link the wires to check if the fan comes on, if not check fan out, if it does get new switch.

Lyn...

[MatBin 5,080]

Check the fuse first.

[Trumpet 215]

If its anything like the older Hondas, the fan switch will only have one wire going to it. It relies on the radiator being grounded. The Radiator Earth was bolted to the fan assembly, which had corroded bolts to the radiator. Running a separate Earth to the radiator mount cured it.

Edited June 27, 2020 by Trumpet

[Newoldbiker 45]

Lyn - when you say 'link the wires' what does that mean?

 

Thanks 

[Griff 1,556]

The fan stopped working on my Triumph Explorer once. The cause of the problem was a very small stone wedged in the Fan. Because the fan motor couldn't turn over the fuse had then blown.

[larryblag 14,236]

On 28/06/2020 at 11:34, Newoldbiker said:

Lyn - when you say 'link the wires' what does that mean?

 

Thanks 

There's probably a single wire on the fan switch (sender). If you ground that the fan should run irrespective of the temperate of the engine. If it does then it needs a new fan switch. If not, check the fuse. If there's a pair of wires pull them off the switch and short them together instead. 

[djsb 491]

I think the fan uses a relay and the sender switch turns on the fan via the relay. The relay is in the same place as the battery. I think you can pull the relay out of its socket. On the relay you should see some markings that state which terminals are for the relays coil and which ones are for the contacts. This info can then help to identify which terminals in the relay socket are wired up to the sender and which ones are for the actual fan. You should be able to turn on the fan from the relay socket by connecting the 2 wires together that normally connect to the relays contacts when it's plugged in. You can do all the tests with a multimeter. When the multimeter is on its high current range (10 Amps DC) there is basically a short circuit between the meter terminals (through a low resistance current shunt). This can be used to connect two terminals together like a turned on switch (which is what relay contacts are, switches).

If you are not confident with electrics then take the bike to a garage.

My fan on my bike is also not working. So I have devised the cunning plan above to investigate further. Might actually get it fixed one of these days.