ok so i had heat issues and i narrowed it down to a bad heater core which i changed yesterday ( all day yesterday ) . Now i have noticed a small leak around my water pump looks like the gasket is going bad. I will change it Monday but my question is i have never one time taken the cap off this radiator to find antifreeze up to the cap when its cold. it gets under pressure when running and i can turn the cap just a hair and let some air out and water will make it to the cap in a sec or two. Think i am losing that much water from the small ( really small) leak around the water pump gasket? When you open your cap with the motor overnight cold is there fluid up to the cap? guidance needed please.

 

radiator should be full nearly to the cap yes. Overflow tank fill to cold mark as well.

 

If you see water, then under pressure you are also losing steam. So yes, it could drop that much from a small leak.

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