engine heating up

[sparacha1]

Hi i have a Japanese assembled Nissan Safari 1995, the radiator is filling the coolant in the water bottle rather than mixing with the radiator, i have filled the radiator with coolant but i find all the coolant has moved to the water bottle and the radiator becomes empty. and the car is heating up if i go for long drives or when the a/c is on.
If it is standing Idle and the a/c is on it starts to heat up as well, does any1 have any reason as to why this is happening? one mechanic i showed it too said it was because the radiator was clogged. i have had it cleaned but its still the same.
please advise the possible reasons so i can have it fixed asap as im not able to drive long distances

[AB]

Welcome to the forum mate, don't forget to put up an intro in the introductions section so people can welcome you.

Theres a few things that can be the cause and I'm sure people will help out soon.

You said you had it cleaned, did you clean it yourself?

have a read of these posts below too...

http://www.nissanpatrol.com.au/forums/showthread.php?2420-overheating&highlight=rodding+radiator

http://www.nissanpatrol.com.au/forums/showthread.php?1384-Overheating-GU-TD4.2T&highlight=rodding+radiator

http://www.nissanpatrol.com.au/forums/showthread.php?243-Reasons-why-your-4x4-is-Overheating&highlight=overheating