Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. The Best Tool to Eliminate Air Bubbles

The Best Tool to Eliminate Air Bubbles

The Best Tool to Eliminate Air Bubbles - main image

One of the most difficult problems to identify when diagnosing an overheating situation is air bubbles that are trapped in the coolant system. The coolant system of any water-cooled engine is dependent upon the smooth and clear flow of coolant within the engine block water jackets, coolant lines, water pump, and radiator. Air bubbles may appear inside the coolant system, which increases internal engine temperature; and if not fixed quickly, could result in serious engine damage.

Air bubbles sometimes arise during the time that mechanics perform coolant service. If not taken care of properly, potential serious damage may occur. To solve this, many experienced ASE certified mechanics utilize the vacuum coolant filler and dub it the best tool to eliminate air bubbles during radiator or coolant service and repairs.

The Best Tool to Eliminate Air Bubbles
Image: FJC

What is vacuum coolant filler?

After a mechanic has completed routine coolant or radiator service, it is common for them to add coolant to the overflow reservoir in an effort to "top off the tank". However, doing so could result in potentially dangerous situations of creating air bubbles inside the coolant system. The vacuum coolant filler is designed to eliminate this by creating a vacuum that removes all bubbles trapped in the line, then adds coolant to the vacuum sealed coolant system. The tool itself is a pneumatic device that includes an attachment that is secured to the overflow reservoir cap. There are multiple attachments available, so a mechanic would need to order several of them to fit most US and foreign applications.

How does the vacuum coolant filler work?

The vacuum coolant filler is an exceptional tool that can prevent air bubbles from being trapped inside the coolant system or remove bubbles that currently exist. However, in order to work correctly, the mechanic should follow specific instructions supplied by the tool manufacturer (as each individual vacuum coolant filler has specific instructions regarding care and use).

Here are the basics on how vacuum coolant fillers work:

  1. The mechanic finishes any repairs or service to the coolant system, or diagnoses and repairs any mechanical issues that lead to overheating.
  2. Before adding coolant, the mechanic uses the vacuum coolant filler to remove any existing air trapped inside the coolant system.
  3. Once the vacuum coolant filler is secured to the overflow reservoir, it is activated and a vaccuum is created. Any air bubbles or debris stuck inside the coolant system will be sucked away through lines, chambers and into the reservoir.
  4. The device remains activated until a vacuum pressure ranging between 20 to 30 psi is achieved.
  5. Once the vacuum pressure stabilizes, the airline is reversed and a coolant refill tube is inserted into a container of pre-mixed coolant.
  6. The mechanic releases the valve and slowly adds coolant to fill the system – without adding any air bubbles to the system.
  7. When the coolant tank is filled to the recommended level, the air supply line is disconnected, the reservoir top attachment is removed and the cap is replaced.

Once a mechanic has completed this process, all air bubbles should be removed from the coolant system. The mechanic then makes sure to inspect for any leaks to the coolant system, starts the engine, verify the coolant temperature and test drives the vehicle.

When you're able to easily remove air bubbles in the coolant system of any vehicle by using vacuum coolant fillers, many overheating situations can be avoided. If you’re a certified mechanic and you’re interested in working with YourMechanic, submit an online application for an opportunity to become a mobile mechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

P0608 OBD-II Trouble Code: Control Module VSS Output "A" Malfunction
P0608 means there is an malfunction in the vehicle speed sensor A control module often due too faulty speed sensor or shorted electrical wiring.
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
How to Service Parking Brake Shoes
The parking brake shoe fails when the emergency brake is engaged but the vehicle does not stay parked and moves position when the mechanism is active.


Related questions

Q: I could not add coolant - in my owner's manual it says the radiator capacity is 5.3 litres

Hello there, radiator flushes on your vehicle do not always get all of the coolant out. Without knowing your make and model I can only offer general advice. When coolant flushes are performed not all of the coolant is able...

Q: Need to change a CV joint

There are quite a few special tools required. Although all of the tools are important, of high priority you will need a high capacity, properly calibrated torque wrench because the CV axle nut is torqued to 188 ft-lbs. For ease,...

Q: Car leaking transmission fluid

Hello! Leaking transmission fluid can be a serious issue, until the transmission leak is resolved caution when driving is recommended. If the transmission fluid is too low, it can permanently damage the transmission. The most common causes of transmission leaks...