electric fans

[geeves]

After removing all the skin from my arms removing the radiator to clean it.(see post in faults) Ive been thinking about an electric fan.
I picked up a double fan out of a Pulsar which is sitting in the garage waiting a rainy day when I have time to design mounts etc but was then having second thoughts.
The different cowling design will alloy easier cleaning in place but will it also mean that when it does clog up it will be more prone to overheat?
How much clearance do I need to stop the fan blades eating the radiator in water?
Where does everyone put the temp sensor to start and stop the fan? Ideal place is in the bottom of the radiator but the pulsar radiator did not have it there. Fitting it to the thermostat housing will work but the fan will come on earlier and run longer. What temp sender do I need?
A cunning thought I had was to remove the cold start sensor and rewire this to a manual button on the dash so If I think its cold so will the engine. Obviously this will be a non locking switch. Is this a good idea? It will leave a suitable hole in the thermostat housing.

[pig75]

You can by or make a fitting that goes into the bottom hose and screw the sender into that. Jaycar have a good kit for controlling fans it has adjustable start and stop temps. I have my fans mounted high on the radiator so if i am going through water the fans should be off before the water gets to them. ( the water should have cooled the radiator down enough too turn the fans off) I also have a switch on the dash so the fans can be on, off, or auto and a LED to show when the fans are on
Jaycar kit http://www.jaycar.com.au/productView.as ... BCATID=347

[MUVIT]

there's about 3 different types of twin thermos on ebay aus :chev camero style . Au ba falcon style : hq . Hx basicly reverse au ba style . I wanted 2 go au ba style but 2 big . Not enough room between fan & a'c unit so i went the chev style . Had 2 shave alot of plastic in fan and a/c area & cut down the width. These r a 2 speed fan & i dont think my mate wired them right from the start. We wired 1 fan 2 run off ignition & the other off thermo switch. Lasted about a year but aleast 10 water crossins without fan kill switch didnt help at all. 2day i changed 2 the hq hx style . The fans r a 1 speed design & fit better just had 2 trim the width

[Captcol]

You guys with electric fans, are you removing the viscous unit and putting these on the back of the radiator or on the front behind the grill?

[pig75]

Mine is on the back

[geeves]

If you can do on the front you prevent the fan ever touching the radiator so this is the ideal way. Dont work so good tho if you still have air con. Mine will be on the back.

[iananita]

I think you would find the fan blades on an electric fan would either stop in water(burn out the motor), not work because of the water or blades are usually too thin to cause any damage to the radiator. With a kill switch on the fans this would avoid any damage to the radiator.

When I did my fan build on the Rodeo (4JB1) I used the thermostat housing, found a Tridon thermo-switch to fit in the blanked off hole. Fans only ran at 87*C (fixed temp) or when A/C on.

By the way, with a shroud around the electric fans it would be harder to clean the radiator in the vehicle.