Reserve Tank Caps
The coolant reservoir serves a dual purpose to allow room for coolant to expand and to hold reserves. As the engine temperature rises and the coolant heats up, it expands, which causes it to become highly pressurized. This piping hot coolant is sent to the radiator to be cooled. As it expands, the overflow is held in the coolant reservoir. Radiator overflow tanks have a removable cap, which allows coolant to be added to the system when low. The majority of coolant recovery tanks have a line that indicates the appropriate level for the coolant. Above the line indicates enough coolant in the system; below the line indicates not enough coolant, which puts the vehicle’s engine at risk of overheating.
Motorad offers a broad line of reserve tank caps.