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7 Causes of No Pressure in Radiator Hose & Fix

The radiator hose is in charge of moving coolant from the radiator to the mechanical components to prevent overheating, which makes it an essential component of your car.

You are usually suggested to check the radiator after performing routine maintenance on your car for this reason.

So, if you observe that the engine is still overheating even though the reservoir is full of coolant, there may be a problem with the radiator

When this happens, there may be no pressure in the radiator hose, which prevents the coolant from removing heat from the engine. 

Stay tuned as we discuss why there is no pressure in radiator hose, the signs of a bad radiator hose, and more! 

No Pressure in Radiator Hose

7 Causes of No Pressure in Radiator Hose

This question may be the first thing that pops into your head as you encounter this problem. 

There are a variety of reasons why this happens, and it can be challenging to find out. The following are the causes of no pressure in the radiator hose:

Your Hose Has Leaks

Your radiator hose isn’t invincible. It can develop surface cracks due to the pressure from the coolant and other external factors.

As a result, the radiator won’t maintain pressure. And because the complete cooling system is not accumulating pressure at this point, the engine will overheat.

Inadequate Coolant Level

When your coolant level is low, the pressure from the expansion won’t be enough to let the coolant run through the system. 

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And when there is not enough coolant to absorb the heat, problems can start to arise. 

Water Pump Or Thermostat Malfunction

If you have a faulty thermostat, the cooling system is unable to release fluid to the radiator.

The thermostat won’t often fully open until the engine works hard, like when slowly and steadily ascending a steep incline.

When the thermostat malfunctions, it nearly invariably happens when it is completely open, enabling the coolant to flow at its fastest pace. 

It won’t be able to warm up if it’s always open, and running it cold is quite dangerous.

Additionally, a broken water pump won’t provide enough pressure to the system for the coolant to circulate.

The radiator won’t operate properly in either of these situations.

Corroded Radiator Hose

Corroded Radiator Hose

There is no question that any exterior corrosion on your car will steal your attention. Even though you can’t see it, the issue may persist and take place in your car.

The combination of metal, liquid, and water makes rust and oxidation inevitable. And because the radiator contains these three factors, rust can become a safety concern.

If your radiator hose is too rusted, it could develop holes, leak, or have other issues.

Gunk Buildup

Any debris or obstructive particles may hinder your radiator’s ability to pump the right quantity of coolant the engine needs.

When this happens, the buildup prevents your cooling system from building pressure, which causes the absence of pressure in your radiator hose. 

Folded Hose

When there’s a dent or fold in your hose, the cooling system may not generate enough pressure. 

The dent could also propagate into a crack and cause a decrease in pressure in the system.

Air Pockets

The absence of pressure in the radiator hose is most often caused by this. 

Regardless of whether you have a malfunctioning thermostat, insufficient coolant, or any other problem, it is imperative to make sure there is no air in the system.

Adding antifreeze is normal for your cooling system. However, when you do this task, you should be wary of air pockets that can form. 

These air pockets can reduce pressure and impede the flow of your coolant.

What Are The Signs That You Have Bad Radiator Hoses

What Are The Signs That You Have Bad Radiator Hoses?

The following indications should be on your radar if you suspect either a bad radiator or bad radiator hose symptoms:

  • Coolant Is Leaking

Coolant leaks can be attributed to these factors: the radiator itself, the drain cock, and the hose. 

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The most obvious sign that there is coolant leakage is when you notice a green and sweet-smelling fluid beneath your car. 

The problem must be identified by a skilled technician because there are many probable reasons.

  • Engine Overheats

Overheating is most frequently caused by a damaged radiator hose. 

Too much pressure in the radiator hoses can cause them to crack and leak over time. 

If the overheating persists, the engine could break down and prevent the vehicle from operating.

  • Low Coolant Warning Light Is On

If you observe that you frequently replenish the coolant in your radiator, there may be a leak in the radiator hose. 

Another evident sign is the illumination of the low coolant warning sign on your dashboard.  

Additionally, drip marks where the car was parked should also indicate this kind of leak.

  • Collapsed Hose

When this happens, there may be no pressure in your radiator hose

An inspection is required when a collapsed radiator hose prevents coolant from flowing as it should.

5 Ways To Avoid The Absence Of Pressure In The Radiation Hose

Here is what you should do to avoid having no pressure in your radiator hose and overheating your engine:

Method 1: Determine The Source Of Leaking

Finding the source of the leak in your hose is a challenging task you can accomplish. 

That’s why it is best to employ the help of an experienced mechanic to search for the leak in your cooling system.

Method 2: Refill Your Coolant Tank

Refilling the coolant in your radiator tank when the coolant level is low may work as a temporary remedy. 

However, you should schedule an immediate inspection since this may indicate there is a leak in your system.

Method 3: Replace The Damaged Thermostat or Water Pump

If the water pump or thermostat breaks, fix it as soon as you can.

Once these parts are damaged, there is no way to fix them.

Experts also advise making the replacement of these parts a requirement for regular cooling system maintenance.

Method 4: Replace A Bad Radiator Cap

If the collapsed or defective cap is the root of the issue, replacing the cap will be the only way to fix it.

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The damage will be irrevocable when you replace the radiator cap with the wrong model. That’s why you must ensure that the ratings of the new and old radiator caps match. 

To make sure everything is still functioning properly, you should also frequently inspect the radiator hose cap.

Method 5: Eliminate Air Pockets

As soon as the cooling system has adequate coolant, leave the tank cap open and compress any hoses that feel empty to the touch. 

Remove the air pockets from your hose by squeezing them and forcing the air toward the reservoir.

Frequently Asked Questions

What Does It Mean When The Upper Radiator Hose Is Soft When Hot?

The rubber that makes up the hose may be damaged when this occurs. This can be caused by an internal engine oil or transmission fluid leak that damages the rubber’s composition. 

How Do You Tighten A Radiator Hose?

The answer is simple if you want to know how to get a tight radiator hose on your cooling system. Use a hose clamp to connect and tighten the radiator hose to the radiator.

However, hose clamps shouldn’t be over-tightened

The hose will be damaged, and the pipe will fail earlier than it would otherwise if too much power is applied to it.

How Much Pressure Can A Radiator Hose Handle?

The pressure in the radiator hose should range from 13 to 18 psi

If the pressure is higher than both radiator hoses are meant to withstand, the hoses will expand and eventually turn rock-hard.

This can lead to cracks because of too much pressure in the radiator hose, which can cause overheating of the engine

How Do You Know If Your Radiator Hose Is In Good Condition?

These are some tips you should follow if you want to know if you have a good radiator hose: 

  • The hoses should be easy to squeeze after the engine has been turned off and has had time to cool. 
  • When finger pressure is applied to hoses, they should be flexible but neither spongy nor soft. Aged hoses will be brittle and rigid.
  • There shouldn’t be any noticeable cracks or bulges, and the size of the hoses should be constant.

So when you notice hoses that are floppy, brittle, bulging, or fractured, you should replace them right away.


Pressure is a crucial element for your car’s cooling system to function properly. 

So when you find that there is no pressure in radiator hose, you should find out the cause and get it fixed immediately.

We hope that this article helped you understand and solve this issue. 

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