I'm using a 2 litre mondeo zetec, (2001) plumbed it all up to the radiator, It runs ok to start, then as it builds up presure its dumping out loads of water out of the expansion tank overflow. It then needs bleeding again as air appears in the radiator. Naturally this is making it run hot.

What have I missed ? as everything seems to be connected right ?

Any ideas or help appreciated.

Scooby.

do you have the water pump going in the right direction.
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[Edited on 9-4-09 by mangogrooveworkshop]

Have you plumbed the bypass pipe into the bottom hose close to the water pump (going in the right direction?) and the hose from the header going down to bottom hose but separate?

Expansion tank should be plumbed into the top of the Ford thermostat

Blacktop or silvertop? As said is the water pump going the right way?

The Green arrows run to and from the radiator sat at the front of the car.

The red with the square is blanked off, and the red arrow goes to the expansion tank.

Any suggestions

Red with blocked end needs to go to a "T" in the bottom hose so there is bypass during warm up. The red arrow head on my car connects with the feed from the expansion tank (with a 15 psi rad cap) also goes to a "T" in the bottom hose. The Ford thermostat has a bypass flow during warm up to stop hot spots in the head until the thermostat opens and normal flow starts. The pressure in the system is quite high and blows past lower psi rad caps ie. Rover.

Do you mean like this, does it make any difference if its A or B ?

Will this mean the excess water is pumped back into the radiatior at the front and not out of the expansion tank ?

I'm using the mondeo tank, with its original cap, what stops the water coming out the overflow pipe ?

"B" but both small pipes go back to bottom hose between the rad and water pump.

You dont actually need to connect the pipe on the drivers side of the thermostat housing.It is the heater feed in the Mondeo.Mine is plumbed in using the left hand outlet to water pump inlet and the header tank is teed into it, the thermostat small outlet at the top is also connected to the top of the header tank.
Paul