Radiator water leak

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Posts: 42
Joined: Mon Aug 26, 2019 8:03 pm
Drives: 2004 1.2 Twist
Location: Midlands

Radiator water leak

Post by Bikergonebald »

My 2004 1.2 petrol has been using a bit of water for a long time. Today I noticed a small puddle under it so investigated.
There is a switch on the side of the radiator that is wet and is obviously the source of the leak. My question is …

Is it most likely something simple like the switch or it’s seal OR more significant like a problem with the radiator.

I’m hoping it’s a common fault so people will know what it is likely to be. Some photos here.
789B72B2-7E96-4F73-B018-46E37A098D7C.jpeg (3.21 MiB) Viewed 189 times
6122C94E-445E-4DB3-A5A9-7007C1E611EB.png (3.44 MiB) Viewed 189 times
A7580449-4D07-480F-8AE2-4869F0D810CC.png (3.51 MiB) Viewed 189 times
Posts: 16
Joined: Sun Sep 21, 2014 11:07 am
Drives: 9N 1.4 TDI AMF 2003
Location: Liverpool

Re: Radiator water leak

Post by Euler2 »

That is the radiator fan switch ( it will monitor radiator coolant temp and switch on the fan if necessary).
You can try to tighten the switch slightly with a spanner as this is how it is installed/removed, but obviously do not over tighten. There is a washer between it and the radiator I think it's a crush washer this is what creates the seal.

Part No: 1J0959481A (new switch with washer)

A new one means draining out the coolant using a drain tap next to the switch or just undo the old switch and drain out the coolant. You can collect the old coolant in a large container and I've seen some people reuse it.

Don't forget to remove the electrical connector on the back of it, and be careful removing using the tab at the side of the connector or you'll break it it.
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