A coolant/antifreeze leak can occur for a variety of reasons, including a blown radiator hose, a bad hose clamp, warped head gasket, or the most common reason, a foreign object kicked up by the truck in front of you penetrating the radiator itself....
If your hydrometer uses a needle, the needle should point to either a specific temperature or temperature range. If it uses a series of plastic balls, the number of balls that can float indicates how well your antifreeze protects the engine from freeze-up or boil over. If the levels are ...