Hi i have a 1995 landcruiser vx fj80 with a 1fze 4500 petrol engine. I have recently discovered that the car starts overheating when climbing hills only and once im on the flat it drops back to half. I have checked the viscas coupling, radiator and water pump but cant seem to see anything wrong. I recently flushed and acid dipped the radiator and i havent gone out on a long drive but kept the revs at 4000 for about 10 mins while stationary and the guage stayed at half ...could i have sorted out the problem by cleaning up the radiator? Do you recommend i change the radiator to a 4 core one as its currently running on the original one. When i bought the car i noticed that the heater matrix was not working and blowing cold cold air only and the previous owner had removed the water by pass pipe that runs parallel to the block on the left hand side and blocked the water pump with a home made gaskit and blocked the water by pass inlet with a rubber hose. I then got an aftermarket steel pipe made and removed the blocked water pump and connected the pipe to the water pump inlet and now the water seems to be flowing in and out of the by pass. So in short i have made two major changes ie the water by pass pipe reconnected and the radiator cleaned out. Has anyone ever had a similar problem?