cooling system problem

Yesterday I had to cross a motorway with 10 km, my GR Y60 2.8 `94` 188000 mileage at about 120-130 km / h. I'm very tip showed the temperature jumped a red box. temp outside was about 24ST. As I left and drove a regular route is a temp dropped to normal and it was around for about 20 minutes I stopped and turned off the engine after 5 minutes I had to continue to drive temp was high and once again began to decline.
My questions:
1. Is this normal, I know the patrol does not like to ride fast and I will not?
2. Do I have a problem with the cooling system?

best regards-rradian

sounds like it could possibly be your thermostat but I'm not expert, I'm sure some one with a lot more knowledge than me will be able to give you a firmer answer

Same as clunk - sounds like the thermostat could be stuck open.

I suppose thermostat but I`m not sure??

+ 1 thermostat.

When engine is cold, then all water circulates around engine. As the water gets hotter then the thermostat opens. Then water circulates through engine and radiator. If the thermostat is playing up then you would see ...
Engine start - indicator shows cold
Engine warming up - Indicator shows warm
Engine hot (thermostat still closed) - Indicator moves towards hot
Engine hot (thermostat open) - Indicator moves towards cold as radiator water enters system

This is pretty much what your seeing.

You could remove the thermostat and then try to test it out of the vehicle by putting it in a pan of hot water and then heating it. You should be able to see it open.

When I do that, my glasses steam up and I never get to see it open...LOL

Gotta watch turning them off when they get to the hot mark
The temp actually rises
Alloy heads dont like the hot,they crack

Thanks a lot . I`is use full information form me. Please tell me If I need exchange thermostat need I pour coolant?