Morris Minor Owners Club

Probably a silly question, but I've got a new 88 degree thermostat in a box but before I fit it - I know that's one of the suitable ones for a 1098cc, but is it better to go for the 82 degree version. (Van lives in Cornish climate, so not many freezing mornings to deal with!)

I think that 88 degrees was originally specified as a 'winter' thermostat but I run it all year round. It's not just for a warmer heater, it'll improve the fuel economy a little as well but probably at the expense of a slight drop in top end power.

Ideal for winter use anywhere in UK. Would fit something lower in summer.

Thanks for that both - I shall go ahead and get the engine running with it and see how I get on!

I used to run an 88 all year round, and got slightly better economy. There aren't many hills around here, so the temperature was OK (I've no gauge, but it felt OK) even on long runs, although I was treating it gently as I was on an economy drive (because of the price of fuel!).

I changed it 1/2 way through LEO for an 82, as on the long hills when the car was already hot (we didn't hang around!), the engine (and my left leg!) got quite toasty (especially when we were running late and playing ketchup in Derbyshire). Probably not warm enough to do damage in the short term, but too warm for me, especially with the scottish bit still to come! It felt cooler after that, (maybe because I switched to long trousers!).

There's a theory that it doesn't matter what thermostat you run, as long as the radiator is big enough to dissapate the heat that the engine puts into the coolant. It's a stable system that will run at whatever temperature the thermostate regulates it too. However, the hotter you run it, the less safety room you have if the engine is (temporarily) putting more heat into the coolant than the radiator can at that point dissapate (i.e. possibly pulling hard up a steep hill).

I guess it's all down to how good your cooling system is, how you drive and what the terrain's like.

Andrew

Exactly right - and in summer the margin for releasing heat is sometimes (but rarely this year) that bit less. In winter - ideal to keep that heater working well! You'll be glad of a toasty leg.