1994 nissan sentra . The radiator was recently replaced . Has mixed amount of antifreeze and water. With the overflow tank also filled with water . My question is i have a bottle of already mixed and antifreeze so when it gets low again do I add the already mixed formula to the radiator itself or the overflow tank .?
The reservoir tank should be filled with 50/50 mixture, not water.
Buy yourself a tester, and draw some coolant into it from your radiator. It will tell you if you have a good mixture, or if you need to add more water or antifreeze. They are very inexpensive.
For topping up, add 50/50 mix to the reservoir. But if you don't have any leaks then you shouldn't need to touch it. My level has remained the same for over 4 years.
Is your car an older model like mines ?
the overflow tank.
check it when you check the oil.
it shouldn't need any once it reaches it's level
As long as you see the reservoir level rise when the engine is hot and fall when cold, all is good and just add as necessary to the reservoir. If the reservoir level never changes, check the coolant level in the radiator ( cold engine).
Both the radiator and the overflow.
Well the bottle I have is already mixed that's why I asked which to add it to but if coolant doesn't burn out that fast then I shouldn't have to touch it no time soon