Morris Minor Owners Club

The thermostat that was removed was rated at 195°F (which is about 91°C for cash). Does this seem right? The engine is a North American spec USHM3 with an induction heater.

Do any official Nuffield publications have this info?

Thoughts.

It could be a 'winter' thermostat installed for the very cold winters.

‘Winter’ would make sense as the last time the car was verifiable on the road was December 1983.

What would ‘summer’ thermostat be? Summers here typ 22° to 28°

The thermostats in the links below will be suitable for your summers

https://www.ebay.co.uk/itm/383514730712 ... Sw08Feppz-
or
https://www.ebay.co.uk/itm/282650678677 ... 101224.m-1

I would suggest that the 82 degree thermostat is the most suitable.

For a side valve engine it should be a bellows stat, NOT a waxstat as linked.

Both types of thermostat are suitable - so long as the thermostat fits the hole it does not have to be a bellows type.
The thermostat (either wax or bellows/alcohol) fitted to a 'A' Series engine requires a 54mm wide recessed seat.
Before the wax-stat the majority of thermostats were of the bellows type including those fitted to the early 'A' Series.
Here is a good article on thermostats:-
https://www.coolcatcorp.com/thermostats ... stats.html

Never really understood why there are "winter" and "summer" thermostats. Even a typical winter 88C thermostat, is going to be wide open way before there's any danger of boiling over in a summer heatwave. I've always left the 88C in all year (and enjoy a hot heater).

Edward1949 wrote: ↑Mon Dec 13, 2021 3:30 pm Never really understood why there are "winter" and "summer" thermostats.

Coldest ever at this house was Feb 2013 and -37 deg C at 5.30 am. This is just balmy December.