Hi all, Hopefully somebody may be able to assist me with a potential problem in my 1996 Toyota Carina E SLI 1.6. Think the engine code is 4AFE on it. The car has a separate cap on the top of the radiator and a coolant reservoir with a small hose which attaches to the top of the radiator...somewhat different to my previous car in which it would appear the radiator was a unit you could not add coolant to but any coolant was added via the small plastic tank. It would appear in the Carina that the coolant in the separate tank is not even warm...even after a long drive...done over 40 miles this evening and checked it after. Furthemore I don't think there is even any movement or circulation of the coolant in this bottle. I noticed Friday evening that the coolant was a wee bit low in it and topped it up. The coolant which I topped up with was a somewhat different colour. Have drove circa 60 miles since Friday evening and when I was looking at coolant this evening it looked like the coolant which I topped up with was still pretty much sitting on top of coolant already in the tank.
Could somebody tell me if this tank is somewhat of an overflow facility or should it be part of the normal circulation of the coolant throughout the running of the motor. If the coolant in it is cold as in after my 40 mile drive does this spell trouble? Also there is no pressure when I remove the top of this bottle after a trip but there is a lot of pressure underneath the radiator cap if I attempt to remove it. The radiator itself seemed hot only pretty much at the very top near the cap and the rest of the radiator was quite cold. While I would expect the radiator to be cold near the bottom I would also expect it to be pretty warm to a mid way point or so down. Finally the pipe from engine to top of radiator seems somewhat airlocked after journey. Not bulging as if its about to explode but some pressure in it all the same. There is plenty of toasty warm air inside the car and the temperature needle rises to an ever slightly below mid way point after 5 to 10 minutes driving from cold and seems to sit at the exact same spot constant. It would appear that there is no gunk underneath oil cap and oil is very clean looking also.
Could anyone let me know if the problem I am experiencing may be related to headgaskt failure or could there be other potential problem(s)?