6 Signs Your Radiator Cap Is Bad

The radiator cap may appear to be a straightforward component, but it serves more purposes than most people realise! How to identify a defective radiator cap

To operate and prevent overheating, your car needs coolant. The last thing you want is for your engine to shut off from overheating because this could cause permanent harm. The radiator cap is one of many various parts that make up the cooling system, but it is also one of its most crucial parts.

When searching online for car garages in Reading and scheduling an appointment with a mechanic, it is advised to have a yearly health check along with a full service performed on your vehicle to prevent being in such a predicament.

The radiator cap is one of the most crucial parts of your cooling system, but unless you're having problems, you probably haven't given it much thought.

How can you tell when a radiator cap needs to be replaced and what function does it actually serve? We'll list all the details you need right here. Let's look at the warnings first.

If you are currently suffering coolant leaks, have your car repair fix them before arranging your upcoming MOT testing service. The most common indication of a damaged radiator cap is coolant leakage underneath the radiator. Additionally, the radiator's top may have dried-out white streaks flowing from it. Your radiator cap may become defective if your coolant level is low.

Here is a more thorough list of the six signs of a damaged radiator cap:

1.     Coolant Leak

Coolant puddles under your car are the most obvious indication that anything is wrong. Because the cooling system in your car is sealed, everything and anything that goes in is meant to stay in. You should look into the issue further if your car has a coolant leak because it can be your radiator cap. Make an appointment with a qualified technician by conducting an internet search for garages in Reading and request a mechanic to carry out a full investigation of the coolant leak.

2.     White Streak on Radiator

Just because your radiator cap is dripping coolant, it doesn't necessarily indicate that it's making it to the ground. If the leak isn't severe enough, the coolant may burn off the radiator before it begins to drip from the bottom because the radiator cap is located at the top of the radiator. If that occurs, the radiator will still have white streaks where the coolant was burned out.

3.     Engine Overheating

Your radiator cap performs a number of functions to maintain the proper operating temperature for your engine. Just be aware that a damaged radiator cap can result in an overheating engine; we'll go into more detail about how it functions later in the post. A MOT history checker claims that this is a frequent cause of MOT test failure.

4.     Low Coolant

Since your car's cooling system is sealed, if there was enough coolant one day in your car, then there should be enough the next. If you discover that you need to continuously be adding coolant, your engine is either burning coolant or leaking coolant. It's on a journey! Check your radiator cap to check if that is where the coolant is escaping from if you constantly have low coolant levels.

5.     Overflowing Reservoir

When the coolant reaches a particular temperature, it produces enough pressure to activate the radiator cap pressure valve, which returns the coolant to the reservoir. However, a malfunctioning radiator cap may overfill the reservoir and cause coolant to leak out of the overflow hose by returning too much fluid there.

6.     Steaming Engine/Radiator Cap

When everything is operating as it should, the radiator cap does a superb job of applying pressure to the system to raise the boiling point of the coolant. However, if your radiator cap is broken, your coolant won't heat up properly and could even begin to boil. As the coolant boils out of the system, there will be a lot of steam coming from your engine or your radiator cap.

What the Radiator Cap Does

The radiator cap may be the cooling system's most underappreciated but also most amazing component. The radiator cap serves four purposes, and if any one of them isn't performing properly, you'll experience issues. These are those tasks:

·       To pump up the cooling system's pressure

·       Surplus pressure is released into the reservoir.

·       Sealing the cooling system

·       Uses a vacuum valve to direct coolant to the radiator.

Your radiator cap pressurises the system first. The coolant's boiling point rises as a result of this pressure. This explains why coolant that is leaking from the radiator cap may burn off on the engine but not inside the system. The coolant will begin to boil without a pressurised system, making it difficult for your engine to properly cool down.

Secondly, while some pressure might be beneficial, too much can be harmful. Hoses, the cap itself, and any other weak points in the system might all blow up under excessive pressure. The reservoir contains an open surplus coolant tube that can safely release the pressure, and the radiator cap has a pre-set position at which it opens to transmit the extra pressure there.

Thirdly, the system is sealed by the radiator cap. It's really simple; after the cap is off, you can add coolant directly to the radiator. However, you cannot have an opening while the engine is running because doing so will cause air to enter the system, which is bad.

Finally, the coolant contracts as it begins to cool, lowering the coolant level in the radiator. To maintain the proper level, the vacuum valve on the radiator cap adds extra coolant to the radiator.