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I have a 95 civic vtec with non vtec heads and my car keeps over heating connected fan to automatically come on when in on position an replaced thermostat an all hoses sons father told me it's my head gasket but not so sure only over heats even I go far distances and warm outside I pull over slowly take radiator cap off let the boiling hot water out and turn car on put normal temp water in it and I'm good for about another 100-150 miles I know I should have 50/50 in it but I go through so much I started using water... But when it overheats its not empty reservoir is still full just have to let hot water out,thinking it may be the water pump but was wondering if anyone ever experienced this? An any idea what it could be..thank you.