Modifying the Westfield Ford Zetec 1800
Cooling System.

Ford Mondeo Bottom Hose

The water pump inlet on Ford Zetec 1800 is at right angles to the cylinder block. This facilitates an easier solution of the bottom hose connection, to the thermostat bypass pipe. Using the bottom hose connection from a Ford Mondeo. (Ford FINIS No: 1013384)  (Left)

 The modification involves cutting the Mondeo hose almost in half, just in front of the reinforced section with the multiple branches.  This end would normally be connected to the Mondeo radiator can be discarded. The remainder provides an angled pipe with a single branch that can be used to connect to the thermostat bypass. 

A separate bypass pipe is still required and can be made from ½” hose connected to the thermostat bypass outlet and clipped securely to the existing coolant pipes. In line pipe connectors of plastic or alloy can be used to join the bypass pipe to the Mondeo hose.  Care must be taken with this installation to ensure coolant flow is not restricted by hosepipes that are kinked or distorted. 

Ford Zetec 1800 Non-Ducted Nose Modifications

Radiator bottom hose connections (Modified)	1800 Sport Carbon showing  modified hose

(Click on the diagram above for the full size picture)

The schematic diagram (above left) shows a modified Mondeo bottom hose connected to the alloy pipe running to the radiator bottom hose. This junction is connected via a new alloy pipe to thermostat housing bypass outlet. The new bypass pipe has anti blow off ends formed by running a weld around the circumference of the pipe  

½” Rubber hose could also be used as a thermostat bypass. Care should be taken to avoid sharp kinks and bends, which would collapse the hose and restrict coolant flow. The rubber hose bypass pipe should be firmly secured, away from the exhaust system. Take care not to crush the pipe at the securing points 

The Photograph (right) shows a Westfield Sport Carbon 1800 cooling system using a modified Mondeo bottom hose, and a rubber bypass hose

(Click here or on the above diagram for the full size picture)

Diagram (above left) shows the Radiator top hose connections modified. An alloy pipe, “J”, from the radiator top hose to the main thermostat-housing outlet this pipe has the junction that was connected to the thermostat bypass. This must be blanked off and sealed. This pipe also contains the thermostatic switch for the fan. If you have a “red top” switch Ford FINIS No: 7001614, replace it with an “orange top” switch Ford Finis No: 7001611

The photograph above right shows the connections to the Thermostat housing. The thermostatic switch (blue plug) can be seen, fitted in to the pipe from the main thermostat-housing outlet. Beneath this pipe is the rubber hose connecting the new bypass pipe to the thermostat bypass outlet. The blanked off connection in the main pipe was made using a ½” BSP adapter and an M10 Bolt.  The pipe was tapped to ¼ ”BSP thread and the adapter was, internally, tapped to match the M10 bolt.  The ¼ ” BSP adapter was wrapped in PTFE tape to seal it and screwed in to the pipe. The M10 Bolt was similarly wrapped in PTFE tape and screwed in to the adapter. This arrangement has proved watertight

Diagram 48 (right) heater connections are unmodified. 

Because of the smaller size of the Westfield expansion tank. To ensure that there is sufficient expansion space in the header tank, the system should be filled to half way between the minimum and maximum marks on the tank

Ford  Zetec 1800  Ducted Nose, Modifications.

(Click on the diagram above for a full size picture)

The modification of the ducted nose is the same as non-ducted nose.  Just the layout detail is different, caused by the radiator being fixed to the nose cone and not the chassis. The diagram (above left) shows the bottom hose connections with a new junction welded to the alloy pipe as before and connected to the water pump inlet.  A rubber hose connects to the new junction to the alloy bypass pipe. Which is connected at the opposite end, to the thermostat housing bypass outlet 

(Click here or on the diagram for a full size picture)

The heater connections are unmodified. 

The diagram (left) shows again the new thermostat bypass pipe and the blanked off junction in the pipe to the radiator top hose. 

Because of the smaller size of the Westfield expansion tank. To ensure that there is sufficient expansion space in the header tank, the system should be filled to half way between the minimum and maximum marks on the tank