What Makes a Car Radiator Overheat?

K-Seal coolant leak repair can seal cracks and holes in your car radiator.

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Why is my car radiator overheating?

If a car’s radiator overheats, this will probably be a direct result of an overheating engine. It is unlikely that the car radiator itself will overheat and cause further problems for the car owner, but if it develops a blockage or a leak the effects can cause significant run-on damage to the overall engine system.

Radiators are comprised of long tubes through which coolant circulates. The primary cause of an overheating radiator is debris and sediment building up inside the tubes and causing a blockage. This then means that coolant cannot pass through, causing the radiator and subsequently the engine to overheat.

Blocked car radiator symptoms

If a radiator does become blocked, you will need to flush it out so that coolant circulation can continue uninterrupted. You should flush it regularly anyway – if you don’t, it may begin to rust and develop the small holes and cracks that lead to coolant leaking out and the engine overheating in the same way it would if the radiator were blocked.

How to fix car radiator overheating with K-Seal

K-Seal can help in sealing those holes – simply add it to a refill of coolant when it is poured into the system and the microfibres and particles in the solution will find the holes and seal them automatically without further blocking the system.

When flushing the coolant out, remember to catch it in a pan or bucket, as it is poisonous to any animals or children that might be exposed to or ingest it.

Want To Know More About Your Car Radiator?

Our complete guide to car radiator leaks will help you get back on the road sooner.

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My 2004 Freelander 1 KV6 had overheating issues. The coolant started bubbling after only a 15 minute drive. LR garage quoted £1700 to fix it. I was advised to try K-Seal. It didn’t work immediately but after a few days the problem was completely gone! No more overheating at all. Very impressed!

Paul Buck, UK View more case studies

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