When I checked the oil and water on my 3.5 I found the waterbottle over full and the radiator empty.It seems that after a long trip the water never circulated back into the radiator.There was no loss of water. I replaced the thermostat 8000 km ago with a original part but not sure if that could be the problem.Any help will be appreciated thx.
Change the radiator cap , the rubber has swollen and wont allow the water back into the radiator. Common problem and the last place anyone thinks to look.
Replaced the radiator cap and no problems on 2 short trips to town.Left dwarskersbos for Tzaneen and 300km later stopped for coffee.Checked and the reservoir bottle full again.Took thermostat out and opened but no diff.Drives 200 km and have to stop and wait so I can take water out of reservoir and put back.Now in Orania and did a gas check but water did not discolour.What now? could it be a head gasket again which I replaced 30000 km ago and if so why? Was under the impression that these 3.5 petrol motors can go forever.Wont see Tzaneen for another week at this rate,please help with advice.
You could have an air leak in the rubber pipe running from the radiator filler neck to the bottom of the expansion bottle. Any leak, even on this line within the bottle, will prevent coolant being drawn back into the rad, leaving more and more coolant in the bottle and less in the rad.
Replaced the radiator cap with a origional one as well as the pipes to waterbottle and seems to be normal again.Thank you for the advice.