Help Please.

[craigcorolla]

Hello fellow climber owners,

Have been doing one up over the last year or so (full strip down) and now fully built . It starts OK and runs OK so decided to take it out the other weekend (to relive my younger days as trials rider !). After about 30 mins one of the water pipes started leaking hot water (couldn't see where) and notest the fan wasn't working, so off to the van and home. Had a look the other day and tried putting a 6 volt battery over the fan and to my delight the fan spun up. So next was the fan switch and once it was removed tried to test it by seeing if it earthed out ie. single pin to body of switch, in boiling water to heat up its got 70 deg. stamped on switch so thought it would work but no. After putting the switch back on I started the bike up and put wire off the switch to earth and still the fan did not come on. This is now p***ing me off after all the work Ive put in doing this bike up. So please can anyone help on the following:-

1.....Should the fan come on by earthing switch out ?

2.....Has anyone got a simple wiring diagram ?

3.....Should the switch earth out in boiling water ?

4.....Can you still get fan a switch/thermostat ?

Thanks,

Craig.

[peterb]

Hi Craig,

I don't have an Aprillia but thought I may be able to help.

The thermoswitch closes upon reaching a certain temp - usually around 80C. I have tested switches with a meter (DVM) set to read ohms, to indicate when the switch makes. Using boiling water from a kettle, pour into a cup and insert the switch with the meter across the terminals - there is a time delay in the switch making - sometimes up to 35 seconds or so.

If not making, then the switch has failed. I'm not sure of the type of switch that you have, it may be the same as an early GG or Beta. If totally different to these models, and you can't get a replacement, then you could easily fit an inline t/switch assy from a 95-02 GG. What part of the world are you in?

Not sure how your system is wired, usually the t/switch is in series with the fan rectifier and simply closes an electric circuit - you mention one leg is to earth - is it? Or, are both t/switch leads not going to earth (ground) as is the norm, ie: one wire is the power lead in from the generator, the other lead joins to the fan rectifier to convert to DC - maybe yours is a different system, hard to know.

Bye, PeterB.

[craigcorolla]

Hi Peter,

Thanks for your reply, Just to clarify the thermo switch on my aprilia screws into the top of the cylinder and has only one spade end (have looked for a broken one and definitely only one.) and one wire going to it, so to test it I unscrewed the switch from the cylinder head and put one lead from a multimeter to the spade and one lead to the brass body on the switch, placed the screwed end into boiling water and tried to "bell" it out, nothing happened ! Don't know if this was the right thing to do, as I haven't got a clue on electrics. So then thought if I start the bike up and put the thermo switch wire to earth "direct" the fan should come on, it didn't. Don't know if this was right but thought I would give it a go ! The bike is now at work so will look at wiring this weekend (work permitting) The bike has no lights so wiring should be simple. I just put wires back in same place as removed on strip-down so they could have been wrong at start. I'm from Bolton/Bury area so I think there are a few trials shops round this area will look them up.

Cheers,

Craig.