Coolant re-route 1800 engine in a westfield

a lot of people have gone on about the poor cooling of the mx5 engine when fitted into the westfield chassis, the biggest issue is now due to fact the the westfield does not have a heater, now this causes problems because when the engine was in the MX5, mazda relied on the heater matrix to provide cooling for the rear of the cylinder block. now the heater matrix has been taken away there is nothing to provide adequate cooling for the rear of the block, as now the water is returned straight from the back of the cylinder head and fed back into the lower water pump inlet completely missing the radiator, and because the thermostat sits right above the water pump the majority of the water just gets pumped directly back up and out the thermostat to the rad, and not actually supplying any cooled water to the back of the cylinder block.

So to cure this problem the solution is to move the thermostat from the front of the cylinder head to the back of the head (this was its original position in the MX6)

to do this you will need the following,

Thermostat cover from an 1800
Thermostat cover from a 1600
1 1/4 aluminum pipe work
2 90 degree silicone bends
1 dog leg silicone bend
1 90 degree mx5 specific silicone bend
(the above were designed by Mark on the forum)
m16 bolt - to fit the 1600 thermostat cover thread
lots of jubilee clips

the pictures below show how the assemble the above parts to move the coolant flow from back to front. the thermostat itself has now be relocated to the back of the cylinder head, which now has the 1600 thermostat cover fitted to it. the bolt fitted is to block off where the 1600 engine has it temperature sensor fitted, on my engine i have relocated my temp sensor to a tapped bolt hole just to the right hand side of the new thermostat cover, all i did was remove the bolt and screwed the temp sensor in with a new sealing washer.
then the first pipe you see is the MX5 specific pipe which bring it to the right angle to start running the ally pipe work towards the rad.
Now in the picture you can see that i have relocated and fitted an after market fan switch into this pipe, now i have done this because my ECU for some reason has decided to no longer operate the original fan switch.
next pipe is the dog leg silicone hose, this then fits to the top hose on the rad after another section of ally pipe work.
you will then need to take off the original water pump inlet fitting and all the associated pipe work with it, and replace all of this with the original 1800 thermostat cover from the front of the head. this will the allow you to take the 2 90 degree silicone hoses and with the aid of a small section of ally pipe work get this pointing towards the bottom hose of the rad. now this small section of pipe work has had 2 pieces of pipe welded to it, one is for the feed from the header tank, the other is for the feed back from the idle control valve, now the idle control valve feed originally connected to the thermostat housing on the front of the engine,but this has now been blocked up.
The original outlet on the head has had a blanking plate make up and fitted, now if you want you can actually remove this fitting all together, but you will need to remove the cams pulleys in order to do this, now seeing as i have already had this engine apart many times, i left this in position for the moment. now one key element to this plate that it is worth noting, is that i have fitted a small M5 screw into the front of this, now this is to enable you to bleed the cylinder head correctly when filling the water system back up, as after the past few weeks i have discovered that the head is prone to air locks if this is not done, and has now actually cured my cooling / air lock issues that i have been having.