coolant boiling over and no fan!!

I've recently rebuilt my '83 1.8 GTI and after running the engine fro about 10 mins the temp reads in the top quater shortly followed by boiling over.  The fan doesn't even think about coming in and shorting the fan switch akes no difference.

Any ideas???

Does the rad get hot?
Bert

after  you rebuilt it did you let your engine run with your heater in the hot position and your expansion cap off to get rid of any air locks ?

The Radiator does get hot Bert, so that rules out the thermostat.  The heater matrix is open and I've blead the system as much as I can so I'm stuck.  The fan is just not kicking in :dontknow:

Any other ideas???  cheers for the help so far though

have you tryed wiring the fan straight to the battry just to see if it works?

is there power to your fan?

are the two wires conected to the sender on the rad?

I haven't wired it directly to the battery yet.  The fan switch on the rad is connected and I have no joy if I short them either!!

If you join the two wires that attach to the fan switch and the fan doesn't work then either the switch is knackerd, the fan motor is knackered or the wiring to the fan / switch is knackered.

Have you checked fuses? Not sure if it is fused in the box or not but have a look anyway.

I've wired the fan directly to the battery and it works fine.  Now it's a case of tracing the wiring back with a multi meter(when I get hold of one).  I checked through the fuse board and all looks good so may be a wiring issue.  Cheers for the help though!!

Have you removed the switchfrom rad  and tested it?
Fill water in a pan, hold switch with pliers in wtaer and keep it there till water starts to boil, you will hear a click on switch and get a reading on multimeter.
Not sure wether you have tested it has you have not stated.
Pete  :wink:

Could be worth checking the thermo switch on the bottom corner of the rad too.

Haven't tested it but surely by shorting the 2 wires that go to the switch I've discounted the switch.  When I short the wires that go to the switch nothing happens so I'm thinking the switch is OK and it's more of a 12v supply or earth issue!

Sounds like a wiring issue then...

Fusebox?
Pete

Your fan will have it's own little loom.The earth wire for the fan is brown and attached to the _ post on the battery,the live feed is red and connected on a red spade near the battery live post.The fan I'm fairly sure isn't fused.Going by what you have tried already a small wireing fault would be a safe bet.I would check the live connector first.I'm sure you will sort this one fairly easily.
                   Best of luck Baller

Cheers everyone, I'll sort it out once I get a multimeter and the rain stops.

Thanks again!!