Can Coolant Cause Rust

Rust in the cooling system can also be caused by air getting into the radiator when the engine cools down. As the coolant cools down, it contracts which can cause an air pocket. … This can cause rusting, while also creating wear on the water pump’s seal and bearings.

Does antifreeze have rust inhibitors?

The green antifreeze contains silicates, phosphates and / or borates as corrosion inhibitors to keep the solution alkaline. As long as the solution remains alkaline, corrosion is controlled and the system is protected. Over time, the corrosion inhibitors will be depleted and the corrosion protection is lost.

Can aluminum be corroded by antifreeze?

Aluminum cooling system components can be corroded by some types of antifreeze, therefore antifreeze engineered for aluminum components should be used when this metal is present. Aluminium corrosion accelerates when the coolant pH reaches levels higher than 9.0.