Should you perform a radiator flush yourself?

Last updated 11/04/2021

Your car’s cooling system is regularly overlooked and taken for granted... until you’re in the middle of a steaming roadside breakdown during peak hour. Suddenly, an early morning meeting has become a last-minute cancellation and the kids are bored in the backseat, waiting for roadside assistance to arrive - it’s all a bit much, even on good days when you’re out the door with time to spare. Instead of hoping it won’t happen to you, make sure it doesn’t and keep your cooling system in check with an engine coolant flush. Never performed one at home? Here’s a few things you need to know before you unscrew the radiator cap.

How radiator fluid keeps your car cool under the hood

Radiator fluid helps keep your engine temperature within optimum range by transferring excess heat to the radiator, where it’s cooled by air flowing through the grill. Coolant contains chemicals to keep it boiling from heat produced by the engine, or from freezing in cold weather. But these properties deteriorate over time. That’s why a regular coolant flush and fluid change is necessary.

What does a cooling system flush do?

A coolant flush prevents your car from overheating by removing gunk and debris that could lead to problems for your engine or radiator. Reducing rust and preserving the life of your engine, this humble fluid also prevents damage to moving components (such as the water pump) by keeping them lubricated.

Choosing the right coolant flush for your car

All flushes are not equal. Be wary of “quick-clean” products – they won’t remove rust and oily residue like an industrial cleaner. Also consider the environmental conditions where you live and specific protection your car needs (such as sealants or anti-corrosives). When in doubt, reach out to mycar and we’ll simplify the process for your by taking care of your radiator.

How to flush a radiator

  • Make sure your engine is cool and remove the radiator cap before flushing the coolant system
  • Drain old coolant by placing a tray under the radiator drain and opening the valve. You may need to jack the car up.
  • Pour in your chosen radiator flush (after mixing according to instructions on bottle) then close the cap.
  • Run engine and blast heaters (check bottle for how long to run engine as it differs between cleaners).
  • Keep an eye on the temperature gauge – don’t let your vehicle overheat!
  • When the engine cools down again, drain your radiator again.
  • Refill with distilled water and repeat the above process.
  • Drain radiator once more before refilling coolant.

Replacing car radiator fluid at home

Check your car’s factory manual and follow coolant fill guidelines. They’ll also recommend radiator cleaner type and amount. Remember:

  • Before refilling coolant, always make sure the engine is cool.
  • Read the bottle - some need diluting, others are pre-mixed.
  • The hardest part is ensuring air doesn’t get trapped – jacking up the front of your car so the fill cap is above the rest of the system will help.

How much does a radiator flush cost?

You can expect to pay around $55, give or take. While the upfront radiator flush cost may be less for DIY, it could be more costly in the long run. If you don’t know your way around your car well enough to perform a radiator flush confidently, safely and correctly, mycar is here to help. We can perform a thorough coolant flush and detect any wider system issues that might otherwise be overlooked. We’ll also have access to the right car radiator fluid, coolant and any necessary extras such as sealants or anti-corrosives, saving you time, stress and oily hands in the process!

What happens if you don’t perform a regular engine coolant flush?

You’ve probably realised by now that we don’t recommend neglecting your cooling system. Skipping your radiator flush can cause a host of problems, including:

  • Engine and radiator corrosion
  • Damaged gaskets
  • Leaks
  • Overheating
  • Engine failure (ouch!)

Is something wrong? Signs of a radiator fluid leak and what to do next

Don’t ignore leaks! The most obvious sign is a puddle under your car. If it’s coloured and feels oily you can bet it’s from the radiator. Have it looked at by a professional as soon as possible. These are some other signs your radiator needs a little TLC.

If you can’t remember your last radiator flush, if you’ve noticed a rising temperature gauge, an odd smell or a suspicious leak, it’s probably time to give your cooling system a detox.

It is important to note if there are cooling system leaks already then there is a possibility that the next weakest link or links in the cooling system could present themselves after completing the cooling system flush.

If you don’t know how to flush coolant yourself or would just rather leave it to an expert - give our team at mycar a call on 13 13 28 or find your nearest store.

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