I know it isn't a Midas, but it does have a K-series, albeit at the wrong end...... I've just posted this across on the GTM forum.
After a weeks ownership of the K3 I have sorted a lot of the little niggles and oddities out. The one bit I'm not having much luck with is the 'cooling' system which is causing me some stress. Please excuse the long post.
Basics first, this is a 1.4 K16 MPi engine with approximately 43000 on the clock, assuming it's the original engine. There's no evidence the engine has been apart, the thermostat arrangement is standard and there is a metro cross flow radiator up front. The gills on the radiator are pretty knackered looking directly behind the air intake, however the rest of the radiator appears fine.
The cooling problems are inconsistent, some days it will behave itself completely over say a 10 mile journey, other days it will overheat 4-5 miles in. Often the temp will drop to the middle of the gauge after raising which I assume is the cold water re-entering the engine when the thermostat opens. On longer, particularly higher speed runs this process repeats itself but with the cooler temperature being higher every cycle. Sometimes giving the engine a quick buzz with the clutch down seems to start the cooling phase off and quite often it will drop to normal.
Throughout all of this the engine runs smoothly without any funny noises or misses, there doesn't appear to be any water in the oil, the car isn't smoking (white or blue) and the car is returning around 35-40mpg. The interior heater doesn't go cold either and there's no bubbling in the expansion tank when the engine is running.
The first issue I found was that the cooling fans (Kenlowes pulling through the rad) weren't coming on, no matter what the temperature. For now I have got them running on a separate switch, though they don't appear to make any difference when the engine starts getting hot.
The second issue was the system wasn't pressurising, closer inspection found a snapped stub on the top of the expansion tank that someone has replaced with a bit of tube 'glued' in place with silicone sealant. As a temporary measure I have epoxied this in place which appears to have done the trick and the system now pressurises. I'm not sure, but I think the coolant level has dropped slightly now.
Obviously my concern is a goosed head gasket, though if it is, it is different to any other blown HG I've ever experienced. Next suspect is the pump, I understand these are pretty much a service item and at 40k it's probably due to be replaced. Do they loose pumping efficiency or do they just leak when they go?
I understand a remote or PRT system from an MGF/Freelander would be a good investment for the future, I assume neither is going to address the basic problems I'm describing?
I'm hoping I'm not the only one here who has had these problems, what I'm really hoping is that someone has found the solution.