Car overheats after driving on freeway for about a hour.

[Kevin]

so i drove home today. i set the cruise control at 100 km/h or 60mph. the temp needle didnt budge. until there was stop and go traffic it started to rise. but then i got past the trafic and got back up to speed and the temp went down again. the needle started to rise again so i pulled into a gas station. i carefully opened up the radiator and added almost 2 litres of coolant. i let the rest cool down. then i drive another 200kms without a problem at all. i had to piss reeaall bad ahah so i pulled into a town.. as soon as i slowed down to 50-60 km/h (abour 30-35mph) the temp started to rise again. i could have made it all the way home. anyway... i did the same thing again. added tons of coolant. looks like the coolant was coming out of the overflow. do you guys think is a blown headgasket?

[mirage83]

Yep. What you're describing with the coolant and overflow tank is an archtypical sign of a blown head gasket. Get a block test and run it, or a compression test if you prefer.

Need to ask though, are you confident of your fan clutch? If it's bad it could explain the overheating at low speeds, though I think it may be too late for the hg even if that is what was going on.

Given the age of the car and that you've been driving it around while it was overheating, if the test is positive for a bhg I'd go ahead and look around for a reputable shop/machinist as your head and/or block may well need resurfacing before putting a new hg on.