Why would a 1994 Chevy Cavalier keep losing water from the radiator?

Answer 1

Check to make sure the plug on the bottom of the radiator is not leaking (where you would drain the radiator to flush it) and check the hoses for cracks. Often a leak will not be immediately visible when the engien is cool. Bring the engine up to "normal" temp, find a convenient place to park and CAREFULLY open the hood with the engine idling and look for steam/drips. Green or orange "rime" on the ends of hoses indicate they are leaking and need to be replaced (tightening won't help). Green or orange "rime" on the radiator indicates you may have a bad radiator.

After you've filled the radiator, check under the car with the heater "on." Look behind the engine (just below the firewall). Drips there indicate a problem with the heater system. Sometimes a metal pipe is used to connect the hoses together when a leak occurs instead of replacing the hose (a major pain) which can then rust out and get pin holes. Smelling coolant in the car is a sure sign that the heater core is broken (as are wet feet!).

Take it to a shop to have the system pressure tested is a good way of finding the problem if you run out of solutions. Expect to pay shop time until they can trace the leak or they may do it for freein expectation of doing the repair work.

The ultimate bad news is a bad head gasket. If the water in the radiator looks like it has cottage cheese in it you have a winner (loser?). A very bad leak will show as water in the oil (milkshake on the dipstick). If you see this DON'T DRIVE until the gasket is replaced, the oil and filter replaced and the system flushed. Water in the oil will RUIN bearings in a short time requiring a full rebuild.

Another way to find the leak (assuming the oil and water aren't mingling!) is to run a radiator flush product (per instructions on the bottle) through the system. This will open up all the spaces plugged by kaka so expect to see holes in short order!