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Just bought a 01 Galant 128k. Engine seems to get hot quite a bit, approaching the red zone but has yet to overheat. Found pure water in the coolant reservoir. Will draining the water and replacing with a 50/50 glycol solution improve the heat loss through the radiator? Or might I have an issue with the water pump?

marked as duplicate by MooseLucifer, Pᴀᴜʟsᴛᴇʀ2, SteveRacer, tlhIngan, dlu Sep 13 '16 at 5:40

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • Also seemingly related, but with a somewhat different focus: Clear water in coolant reservoir – a CVn Sep 12 '16 at 17:53
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    I agree it's a duplicate, and I agree you have an issue with the cooling system. – MooseLucifer Sep 12 '16 at 19:49

Cooling replacement will not solve the problem. Water should handle it. The problem might be in Thermostat or Water pump. On water pump usually first goes bearings - getting rusty and wears out. It happens if you buy a car which haven't been driven for 2 years.. When the bearings are shaking, the impeller is touching the walls and grinds down until breaks. So you should hear a whining bearing noise. If you can see or reach the water pump pulley, you can give it a shake, should feel it through tensioned belt. If it is thermostat, it is easier to replace it than to test it. It is accessable on your car. But it also could be your cooling fan relay. Check if it turns on when the water temperature goes over 90°C or over the middle of a gauge. If it doesn't turn on, it can be thermostat or fan relay, because thermostat don't let the hot water in radiator so the relay don't know that it's hot...

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