overheating, no fans kicking in

[chieflief]

Hey, 1996 Elise s1 bog standard. Sat in traffic and hit 115 degrees briefly, but the fans didn't kick in. Temperature is fine while moving. Apparently there is current getting to the fans, but not turning on. Is it just easier to replace the fan, or should I try to diagnose a rusty connector or whatever else it may be? Just had the coolant changed, garage couldn't get the fan to turn on (it seemed to work before), definitely confirmed when I hit 115. Also, I am assuming it is the single fan unit since I haven't actually had the clam off to have a look yet. Any help/advice is appreciated!

[Arisutea]

chieflief said:

Hey, 1996 Elise s1 bog standard. Sat in traffic and hit 115 degrees briefly, but the fans didn't kick in. Temperature is fine while moving. Apparently there is current getting to the fans, but not turning on. Is it just easier to replace the fan, or should I try to diagnose a rusty connector or whatever else it may be? Just had the coolant changed, garage couldn't get the fan to turn on (it seemed to work before), definitely confirmed when I hit 115. Also, I am assuming it is the single fan unit since I haven't actually had the clam off to have a look yet. Any help/advice is appreciated!

I would try and diagnose the fault first before taking the car to bits. There is a sensor you can disconnect on the engine (I forget exactly which one) which makes the fan run regardless what temperature the coolant is (it is a safety measure in case the sensor fails).

Something to check with everything in place... can you physically turn the fan? i.e. does it spin freely, or has the fan seized solid/hard to move? You should be able to remove the grill on the front and turn it by hand/stick (depending how long/short armed you are!).

It is a clam-off job to change, and I believe the early Elises only have 1 fan. Check eliseparts.com / elise-shop.com etc. for the right one to get. I'd recommend you stick with the standard Spal fan, it is designed to go in an Elise (i.e. upside-down under the radiator), where as other fans are not (so get full of fluff/leaves/water and fail sooner).

[chieflief]

Arisutea said:

I would try and diagnose the fault first before taking the car to bits. There is a sensor you can disconnect on the engine (I forget exactly which one) which makes the fan run regardless what temperature the coolant is (it is a safety measure in case the sensor fails).
Something to check with everything in place... can you physically turn the fan? i.e. does it spin freely, or has the fan seized solid/hard to move?

I have managed to rotate the fan blades a quarter turn in both directions and that's it. Should I still bother to do the sensor thing? I am assuming that the fan will need to be replaced now that I know it won't rotate without quite a lot of force, if at all. The car has been up to 114 degrees while stopped in traffic (twice, briefly), and the fan hasn't come on. Again, I am assuming the temperature sensor is not faulty.

[cbaileyuk]

If you are fairly certain that the fans are at fault, you need to stop exposing the engine to high temperatures. If that means stop driving it, then stop driving it.

Get the fans swapped bbefore need to swap more than just fans.

[chieflief]

cbaileyuk said:

If you are fairly certain that the fans are at fault, you need to stop exposing the engine to high temperatures. If that means stop driving it, then stop driving it.

Get the fans swapped bbefore need to swap more than just fans.

Fortunately I live in a country that has a lot of cold air - I've had no problems 'till now. For all I know the fan could have been out of commission for three years! I'll order a new one and keep the temp down in the mean time (ie. lots of fast-moving air through the engine bay)! Thanks for the tip.

[cbaileyuk]

chieflief said:

Fortunately I live in a country that has a lot of cold air - I've had no problems 'till now. For all I know the fan could have been out of commission for three years! I'll order a new one and keep the temp down in the mean time (ie. lots of fast-moving air through the engine bay)! Thanks for the tip.

Good work. You'll thank me for that when I've saved you an engine rebuild. Let us know how you get on.