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Clogged Radiator or Blown Head Gasket? (How to Tell)

When your car is experiencing problems with overheating or poor engine performance, it can be difficult to determine whether the issue is related to a clogged radiator or a blown head gasket.


Both problems can have similar symptoms and can be caused by a variety of factors, including neglecting regular maintenance, poor quality coolant, or driving conditions that put extra stress on the engine.


One way to know the difference between a clogged radiator or blown head gasket is to check the engine oil filler cap, if it's milky and frothy it's likely to be a blown head gasket.


In this article, we will discuss the signs of a clogged radiator or blown head gasket, as well as how to diagnose and fix each problem.

 

Table of Contents:


a person removing a damaged car radiator

Signs of a Clogged Radiator

Below are some of the common symptoms of a clogged radiator.


  • Engine overheating or a high coolant temperature: One of the most obvious signs of a clogged radiator is a high coolant temperature or engine overheating. This can be caused by a buildup of debris or corrosion inside the radiator, preventing proper heat dissipation and coolant flow.

  • Coolant leaking: Another sign of a clogged radiator is coolant leaking from the system. This can be caused by a crack or hole in the radiator or damage to the hoses or fittings, sometimes the higher pressure caused by the radiator blockage can cause coolant leaks.

  • Visible damage to the radiator: Inspect the radiator for visible damage such as bent fins or corrosion, this could be indication that the radiator is clogged.

  • Discoloured coolant: If you notice that the coolant in your car is discoloured, it could be an indication that the radiator is clogged. Coolant should be a clear or yellowish colour (sometimes pre-mixed coolant is blue or other coolers). If it appears brown or rusty, it may contain debris or rust that has built up inside the radiator.


Signs of a Blown Head Gasket

Below are some common symptoms of a blown head gasket.


  • Overheating engine: A blown head gasket can also cause an overheating engine, as coolant may be leaking into the engine, reducing the amount of coolant available to keep the engine cool.

  • Milky and contaminated engine oil: One of the most telling signs of a blown head gasket is a milky or frothy substance in the engine oil filler cap. This is caused by coolant leaking into the engine oil.

  • White smoke from exhaust: Another symptom of a blown head gasket is white smoke coming from the exhaust tip, which is caused by coolant being burned in the combustion chamber.

  • Poor engine performance: A blown head gasket can also cause poor engine performance, as the engine may not be able to build up enough compression or may be losing power due to coolant leaks.

  • Rough idle: If your engine is experiencing a rough idle, it can be a sign of a blown head gasket as the compression is not consistent across the cylinder.


a blown head gasket

Clogged Radiator or Blown Head Gasket?

If you're experiencing one or more of the symptoms listed above, it can be difficult to determine whether the issue is related to a clogged radiator or a blown head gasket.


One way to know for sure is to check the engine oil filler cap. If it's milky and frothy, it's likely to be a blown head gasket. However, it is important to seek professional help for proper diagnosis.


What Can Be Mistaken for a Blown Head Gasket?

There are several other problems that can be mistaken for a blown head gasket, including a cracked cylinder head, a cracked engine block, or a leaking intake manifold gasket.


These problems can also cause similar symptoms, such as coolant leaks, poor engine performance, and overheating.


Can You Drive With a Clogged Radiator?

It is not recommended to drive a car with a clogged radiator. Clogged radiators can cause engine overheating, which can lead to serious damage to the engine and other components. It can also lead to a complete breakdown of the car, putting yourself and other drivers at risk.


If you suspect your radiator is clogged, it's best to have it checked and fixed as soon as possible.


Can You Drive With a Blown Head Gasket?

Driving a car with a blown head gasket is not recommended, as it can cause serious damage to the engine and other components. It can also lead to a complete breakdown of the car, putting yourself and other drivers at risk.


If you suspect you have a blown head gasket, it's best to have it checked and fixed as soon as possible.


How to Fix a Clogged Radiator

Fixing a clogged radiator typically involves using a coolant system cleaner and distilled water. Here's a step-by-step guide on how to fix a clogged radiator.


  1. Obtain coolant system cleaner and distilled water: Before you begin the process of cleaning your clogged radiator, you will need to obtain a coolant system cleaner and distilled water. The coolant system cleaner is a specialized product that is designed to remove debris and buildup from the inside of the radiator. Distilled water, on the other hand, is used to flush out the cleaning solution and any remaining debris.

  2. Mix distilled water with the recommended amount of coolant system cleaner: Once you have the coolant system cleaner and distilled water, you will need to mix them together in the correct ratio. The recommended amount of cleaner will vary depending on the product you are using, so be sure to follow the instructions on the packaging. Typically, the ratio is around 1:1 or 2:1 for coolant system cleaner to distilled water.

  3. Drain the radiator using the drain valve: Before you can add the cleaning solution to the radiator, you will need to drain the coolant from the system. The radiator will have a drain valve located at the bottom of the unit. Open the drain valve using a wrench or screwdriver (or whichever tool is required) and allow the coolant to drain completely out of the radiator.

  4. Fill up the radiator with the mixture of coolant system cleaner: Once the radiator is drained, close the drain valve and fill it with the mixture of coolant system cleaner and distilled water. You will want to pour the solution in to the recommended level.

  5. Allow the solution to sit for 5-10 minutes: After the radiator is filled up with the cleaning solution, allow it to sit for 5-10 minutes. This will allow the cleaner to start breaking down any debris or buildup inside the radiator.

  6. Run the engine for 5-10 minutes to circulate the mixture: After allowing the solution to sit, start the engine and let it run for 5-10 minutes. This will help to circulate the cleaning solution through the entire cooling system, ensuri