Ran my Pantera last week first time in couple of years (weather here is dire).

Ran for an hour no steam / no pinking detonation / no alarm (goes at 200F I think) but temp gauge was at max - over 240F!

Took it for a blast and it sounds good no alarm but did steam a little.

Runs fine but what should I do to be safe?

uhhh 240 is wayyy hot

170-180 if fresh water cooled - 140-165 if raw water cooled. Then there is your oil temperature.

I've heard that with a thermostat removed and raw water cooled you should be sitting at about 120ish* depending on the lake water temps.

Though I am NOT a mechanic, I know 240 is WAY TOO HOT to be running it.

Again, I'm not a mechanic, but if your boat was truly running 240*F I dont think it would run long. I would lean towards a faulty gauge. Have you checked that?

x2

you would have had a alarm way before 240,check guage&sending unit.

Another thought could you possibly be looking at the oil temp gauge?

many thanks for ideas - oil pressure is good - that gauge is also a bit odd as pressure goes up after time?? Can i check gauge/sender in hot water or do I do a resistance check from ambient to 'hot'?

Go over your ground connections behind the dash, my 2 cents is on electric gremlins.