I was given the understanding that what is called above a swirl pot, is actually an expansion vessel. Such vessel wouls servre to opose shock waves in the cooling system arising from opening an closure of the thermostat. Shock waves can cause damage in piping.

Bert's explanation is slightly different to the version I heard:
The swirl pot was added to reduce thermal shock to the radiator when the thermostat opens and suddenly floods the cold metal with piping hot coolant.
Both seem possible and are not mutually exclusive of course.

That sounds closest to its intended function and concurs with the explanation given by a dealer, temperature rather than physical flow shock.

I would. Too much of a pain in the arse I’m afraid. My list of problems and the length of time actually at the factory in the last 12 months is too much to justify the price. It’s about to go in again.

Did you have more problems than the three wheeler ? On my car exception of the brakes and the radiator , i have almost no other problems ( the fuel cap is sometimes difficult to remove and the wind into the cockpit,but it is solved) . For the rest the car is 100 percent better than the trad. Sometimes i am thinking she likes too much as an modern car.

The Three Wheeler is in a league all of it's own albeit that is all ok now. This Plus Four had the upgrades done like all others including new radiator. All of the holes in the uprights either side of the windscreen corroded and the uprights were replaced. Apparently the holes were too small for the bolts that were inserted resulting in a crack in the paint. I think the holes are bigger on more recent cars but I would urge anyone with a car as old or older than mine to check. Mine was built in Nov 2021 Everyone needs to keep their eyes on that one because I think it's common. The seals on the doors are next to useless in that water gets into the footwells. Despite going to Morgan twice the wind from the passenger side is unbearable on the driver when there is no passenger never mind the passenger. On the passenger side the panel in between the front of the door and the bonnet there was what appeared to be a large blister. It went in for repair before Christmas. Came out perfect and it has now already reappeared so it's going back again. It cannot be corrosion so suspect it's a stress thing from the door. I had the fuel filler cap problem too but that is now sorted. The windscreen heater elements as on my previous ones has already started to break down. Four of the lines don't work so I'm keeping my eye on that.

Albeit I am very disappointed I do agree the car itself is better than the trads I had previously. I know somebody will jump on me now and say "ahh but it's a Morgan". To that I say cobblers it was £80,000 and I don't expect more wind on me in the cabin than the trads I had previously. It's a design fault without a shadow of a doubt and on the gale entering the cabin the Trads win hands down.

My car is now at the dealer, according the manager of the garage they have modified the radiator on 180 cars (belgium,france,germany).
Untill now no one have a leak again.

My Plus Four came back from the garage today with a new "improved" radiator fitted. Hopefully that will be the end of my troubles after 2,500 miles in the two years since i purchased it new.
but i intend to check the windscreen uprights tomorrow.

I have had difficulties with the fuel cap and this is to be replaced when i next call in at the garage.

Brakes - when i first drove the car the brakes did not seem to "bite" as they should but over time I have either become used to them or they have bedded in and in event now cause me no problem.

I went for 20 mile drive this afternoon which happily reminded me why i had purchased a Morgan.

The explanation for the need to fit a swirl pot (trauma shock when the thermostat opens to let hot water flow) seems to cogent but it may be a combination of the two factors mentioned. It would be interesting to have a list of comparative mileages and an analysis of types of journeys undertaken. Use mainly for short journeys (say 15-20 mile) would result in more thermal shocks than use once a week for a 100 mile journey (although the average monthly use would the same as regards mileage). Again an motor engineer may wish to consider this aspect.

What does seem clear from those reporting radiator fault is that before the swirl pots were fitted the damage was cumulative (further damage each time the engine was started) and that the leaks were caused by the warming and cooling of the engine. It may therefore be postulated that MMC must have known that when a swirl pot was fitted there was already damage to the radiator and the radiator should have been replaced at the same time to avoid trouble in the future (a long drive to the continent this coming Summer). Others may wish to comment on this aspect.

IAlso is there anyone out there who is able to comment as an motor engineer on the difference between the original radiator and the new improved radiator which is now being fitted.

Apologies for interloping onto the CX forum from the point of view of a 4/4 owner.
BUT I had to mention my 4/4 radiator failed too. (Replaced by me with relative ease).
IF I were a wealthy man I still would not be deterred from owning a CX despite all the annoying faults reported.

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