Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing 2008 4/4 temperature issue

Maybe time to try a bypass hole in the thermostat periphery Neil. Another thought is the efficiency of the water pump given age of car. If the coolant flow was below par it could cause latency in response to changes in engine power demand and speed.

That looks better Neil.....

Perhaps that’s the delay or lag mentioned in my last post. When the engines load increases the stat doesn’t respond quick enough. That’s why the early Duratec engines had stat heaters. The ECU would see the engine load and switch the heater on to kick the stat into action.

Yes, you could try and decrease it but don’t forget this is counter intuitive. My money would be on increasing it a little bit at a time. Or maybe leaving the blocking like that and now consider combining it with a lower 82C opening stat?

NB - Just be aware to factor in the ambient air temp each time you test as that will affect the Delta T of the rad from one day to another. And don’t be surprised either if the car runs hotter in winter too.....

Mnnn, maybe ll try increasing it a bit first then, i’d rather not drill holes in the stat as they’re awkward to get to and pricey as they come as a moulded in component, nothing’s simple is it!!!🤔🤔🤔

I attached two vertical covers to the left and right sides of the radiator. This will ensure that the radiator continues to function properly. I did it intuitively; I'm not a physicist. But if you cover the entire width of the lower surface of the cooler, I could imagine that an entire working section or temperature range of the cooler would be blocked, because the heat varies from bottom to top and not from left to right. Left and right side added together I covered about 30% (or 40% ?), so the surface area is now approximately the same size as the original cooler. You can test it with different areas to get the best result. For me, this keeps the temperature fairly constant, just like with the old cooler. It is enough for the valve to open. I wouldn't cover any more than that to avoid new problems when driving in warm weather, e.g., in stop-and-go traffic or in a traffic jam.

This is how it looks from below

Amazing what you can do with cardboard and gaffer tape ! ? And it works which is a plus …….. MM
PS perhaps it’s just my poor phone picture ?

It was actually just a temporary solution until I could do it properly with aluminum surfaces. But, crazily enough, it's already lasted three years, it is a type of waterproof plastic cardboard that can withstand the heat reasonably well

Heinz, it is Northern (England/ish) humour and often it takes a while to understand.
I have a pair of sports shoes, holding up the float in one of our toilets……..it’s been like that since August 2024……I have been too busy to repair it but thankfully we have 5 toilets in the house, so it is not causing a problem !
Stick with your current repair.
MM

FIXED!!!!!
I tried the suggestions about blanking plates for the rad to no avail. Decided to go back to basics and get the cooling system flushed through. Engine block and heater matrix flushed through separately. There’s a short hose that runs from the rear housing on the head to the heater matrix. This little hose has a spring in it in order to stop it from collapsing I guess. The spring had caused a blockage in that small hose which was easily flushed out. The car is now running at normal temperatures under load and on tick over in a queue. The fan cuts in and now the temp immediately drops unlike before. Many thanks for all of the suggestions, and the time taken by my Morgan friends to write them. Just goes to show that going back to basics sometime is the best way.

Fantastic result Neil, well done