May be located in the head nearest the firewall on the driver's side. That's where it is on my 95 3100.
most coolant is 50/50 mix. however in arctic climate it is 50/70 mix
The engine computer uses the signal from the coolant temperature sensor to decide when to activate the radiator fan relay.
Radiator coolant.
These fuses and control unit control that big fan motor on your radiator.
Coolant goes in the radiator or you can also fill the radiator resevoir.
Low coolant, radiator restriction.Low coolant, radiator restriction.
In systems that do not have a radiator cap, the coolant is drained by the radiator drain plug. It is filled by adding coolant to the system through the overflow bottle.
Using straight water in place of coolant will increase the chance of rust occuring within the cooling system and clogging up the radiator. Depending on the climate you live in, you will risk the possiblity of the engine freezing and cracking the block.
If the radiator is cracked then the vehicle has ran dry on coolant. This would cause the radiator to crack if there wasn't any coolant.
You add coolant to a C240 at the radiator overflow tank. This allows the radiator to suck in coolant as needed when hot.
Low coolant? System airbound and needs to be purged? Water pump not circulating coolant? Heater control valve? This happens to me on my 99 at the start of each winter. the damper "Sticks" in the shut position but eventually starts to working again after fiddling the climate control temp settings.
One flushes a radiator by draining the radiator, rincing the radiator, and then by adding a new coolant. One should remember that the drained coolant is toxic.