Under my 1.6 pt.1 : Leaking waterpump

[Grapes]

Bolts acquired! Thanks to the Burton Car Company (Beautiful 2CV based old school roadsters). They where actually closed for customers but where polite enough to help me which is really cool.
Also managed to extract the rest of the bolt with pliers and fitted the new pump so that's good. I fear the next repairs will be much more difficult.

Also I've done some more testing since I started typing and the radiator fan doesn't turn on

(the manual said to fill the coolant, close the system, start the engine and let it run until the fan turns on but it never did)

Turned it of quick when I noticed that.

How to proceed?

[suffolkpete]

The switch is situated near the top of the radiator on the left hand side.  You can reach it from beneath the car.  To test it just bridge the terminals with the ignition on.  Before you condemn the switch, check that the radiator is full, there is a de-gassing hose that runs from the top of the radiator to the header tank.  This can get blocked by sludge collecting at the lowest point under the car, so it needs to be blown out.  The switches are easy to obtain and replace.

[Grapes]

Sludge sounds very likely... Any particular way to blow this out or just disconnect both ends and blow hard in one end?
Any safe additives that can clean the system?

[suffolkpete]

Clamp the overflow pipe shut, disconnect the degassing pipe at the header tank and put your finger over the tank outlet.  Blow into the header tank as hard as you can until clean coolant with no bubbles comes out of the hose.

[Grapes]

Excellent, will do!