Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Zetec cooling system advice required.

Paul, puzzled with what you have found; I have a Zetec 2.0 BlackTop (ex Mondeo) in a 4/4. As std on the Ford system there is a small (~0.5 inch bore?) bypass past the thermostat that re-enters the system just before the pump so that there is uncooled circulation through the head before the thermostat opens at which temp the bypass valve is closed, then all the water goes through the rad. then it is controlled by the thermostat. If the thermostat is working as it should then the coolant should be at thermostat temperature of around 92 C and full open 106 C. Mine sits at around 90 C (27 year old gauge and sender) only goes much above on a thrash on hot summer days.
I run a 1986 4/4 rad with an unpressurised overflow bottle that allows coolant to be sucked back into the rad, works well.
I guess you characteristics are due to the system you have installed. Surprised the std circuit was changed by RaceTech (?) Regards PJB.

Hmm, it's a bit of a mystery, but it seems to work. Essentially, the system has a Raceline water rail, which moves the thermostat to the side and n/s front of the engine. There doesn't appear to be any sort of bypass, until the thermostat opens, and the only venting is now above the thermostat housing, into an open tank, just so that one can see what, if any, the losses are. It will not suck it back into the system.

After a couple of good runs of over half an hour and 20 - 30 miles, the temperature seems to stabilise at around 80 degs c. whilst on the move, but no coolant has gone into the catch tank yet, maybe it will if stuck in traffic? Interesting, more testing is ongoing.

I wouldn't imagine at 80 degrees the catch tank would get any coolant if the system is correctly filled.

I see, so Ford think it best to allow uncooled coolant to circulate through the Zetec cylinder head before the thermostat opens to ensure there are no hot spots and local nucleate boiling, and Raceline decide to do away with this feature - ah. What's that all about then? Maybe there is not room for the Ford thermostat housing as the Zetec engine in 4/4 original fitment is about 3 inches further back than the CVH in 4/4.
Regards PJB.

Quite so Peter, but Raceline say that they have never had a problem with this set up, and it does seem to work. You can see the thermostat controling it all on the temp. guage, quite interesting to watch in fact. I'm please that the block is iron and not aluminium though......