A few days ago, temperatures reached around 34°C in parts of the UK, making it one of the hottest days many classic car owners have experienced this year.
While most classics can comfortably cope with warm weather, prolonged periods of heat can expose weaknesses that may have gone unnoticed during cooler months. Older cooling systems, ageing rubber components and vehicles that spend much of the year in storage can all become more vulnerable when temperatures rise.
The good news is that most heat-related issues are preventable. A few simple checks before heading out to a show, club event or weekend drive could help you avoid a breakdown and keep your classic running at its best.
Can hot weather affect a classic car?
Yes, many classic cars were designed before modern cooling systems, traffic conditions and stop-start driving became common. While some classics were originally sold in much hotter climates than the UK, age often becomes the biggest factor rather than design.
Heat can place additional strain on:
- Cooling systems
- Radiators and hoses
- Tyres
- Batteries
- Fuel systems
- Interior trim and upholstery
According to the UK Met Office, the UK has experienced increasingly frequent periods of unusually high temperatures in recent years, including temperatures above 40°C in 2022.
Why should you check your cooling system before driving a classic car in summer?
The cooling system is one of the most important areas to inspect before a summer drive.
The AA and RAC regularly report overheating as one of the most common causes of vehicle breakdowns during hot weather. Low coolant levels, ageing hoses, blocked radiators and faulty cooling fans can all contribute to rising engine temperatures.
Before heading out:
- Check coolant levels when the engine is cold
- Inspect hoses for signs of cracking or deterioration
- Look for leaks around the radiator and water pump
- Ensure cooling fans are operating correctly
- Remove debris from the front of the radiator
If your vehicle is currently undergoing repairs or restoration work, our guide to Classic Car Restoration Insurance explains how specialist cover can help protect your investment during restoration.
What are the signs your classic car may be overheating?
Many classic car owners know their vehicle’s normal operating temperature.
If temperatures begin climbing higher than usual, particularly in slow-moving traffic, it could indicate a developing issue.
Common warning signs include:
- Temperature gauge rising higher than normal
- Steam from the engine bay
- Coolant smells
- Visible coolant leaks
- Reduced engine performance
If your vehicle starts overheating, pull over safely and allow the engine to cool before investigating and never remove the radiator cap while the engine is hot.