Why should you replace the radiator in your car?
One of the greatest improvements in car reliability has been that modern cars are very effective at keeping the engine (and engine bay) to the correct operating temperature. This is because manufacturers have increased cooling capacity and air flow in and out of the engine bay. The majority of classic cars have marginal cooling systems. With modern, slow moving traffic in towns and higher speeds on motorways often classics will suffer from overheating, even if the original system is in good condition
But it is worse than that. Over the decades, scale builds up in the waterways of your cooling system, much in the same way as your kettle does. If coolant has not been changed regularly, or tap water has been used, this scale massively reduces how much heat the radiator in your car can transfer to the air around it.
Simply put: If the coolant does not move freely around the radiator the car will run hot. This puts unnecessary pressure on the radiator, hoses and gaskets in the engine leading to an expensive failure.
Radiator cleaning
Prevention is cheaper than replacement: One of the simplest ways to improve this situation is to regularly (every 2 years, regardless of mileage) change the coolant (or antifreeze) in your car. During this change of fluid, you can use a radiator cleaning solution, which dissolves the scale, and protects the waterways inside the engine and radiator.
As part of our service schedule we carry out a number of these every week, and can prove that this simple job massively reduces engine temperatures and component failure.
Radiator upgrades
For most classic cars, there are ‘upgraded’ radiators available. These have more cores than the originals giving a greater surface area. More surface area means more heat is lost to the air as it passes through the radiator.
Beware of ‘cheap’ aluminium radiators often available on eBay. Although they can be a good thing, aluminium does not transfer heat as well as traditional copper core radiators, so you need to buy one that is thicker than the original for it to be any better. Thicker ones might not fit in the same space and be a bigger job to fit than you were bargaining for.In the Classic Collective workshop we would always use tried and tested products from a specialist marque supplier.
Combined with a lower temperature thermostat (which ensures that the cooling system starts circulating the water faster, giving less time for the temperature to build up) simply replacing an old radiator will dramatically improve classic car reliability.