Thorneycroft T90 running temperature

[Tarka1]

Is this normal.....
As the engine is warming up the temperature gauge shoots over to 100 deg before dropping to 90 ish. I've only noticed this recently and I'm sure it used to get to 90 deg and stay there.
I've fitted a new thermostat (82 deg) but no change - have I got anything to worry about?

 

[searover]

Hi mine rises to 82 and stays there only goes up to just under 90 when full throtle for longer periods but no higher , check your strainer and or blockages youll maybe have to check your waterways in the heat echanger etc.... good luck

 

[Stix]

Hi , mine behaves exactly like searover.

 

[chas]

Could be a lazy thermostat opening too slowly. I had a bit of a problem last year with a T90 and a new thermostat that would not open. I noticed that there was no little hole in the thermostst to vent the air from under it and I had an airlock there. I drilled a small hole in the disk and it has worked ever since, running at 75 to 80 degrees.

 

[Tarka1]

Sounds like a possibility - thanks