Advice for Grads of Mechanic Programs Working on Contaminated Brake Fluid Reservoirs

The role that brake fluid plays in the operation of most vehicles is a vital one. Without it, transferring the force applied to the brake pedal into the pressure that activates the brake pads would be next to impossible. However, in order to be effective, brake fluid must maintain its specific chemical properties. Here are some ways that this delicate liquid can be disrupted, diluted, and disabled by outside elements.

The Many Different Kinds of Contamination

Brake fluid is housed in the brake fluid reservoir, located in the engine compartment. This plastic reservoir should be checked and topped up on a regular basis as part of routine maintenance. And after every top-up, the cap should be firmly closed in order to avoid contamination.

Inevitably, though, grads of a mechanic program will see that this reservoir is often the entry point for any number of substances. If a reservoir is improperly sealed or damaged, dirt, dust, and rainwater can enter the brake fluid system. Eventually, these elements will impact the copper and water content of the brake fluid, as well as increase the chance of corrosion within the braking system. This can result in sluggish or “spongy” brakes, which can deteriorate until there’s barely any response from the brake pedal.

The ill-effects of contamination can be overcome by regular flushing of the brake fluid. This is done by extracting all liquid present in the reservoir, brake valves, and ABS system, and adding new brake fluid. It’s an important task that should be carried out every 35,000 kilometres as a regular maintenance task.

Become a Mechanic and You’ll Inevitably See Examples of the Wrong Product Added to the Reservoir

It’s an easy mistake for an inexperienced vehicle owner carrying out DIY maintenance to make—adding something other than brake fluid to the brake fluid reservoir. Both motor oil and washer fluid are liquids that can often end up being mistakenly poured into the reservoir. This will typically float on top of any remaining brake fluid within the brake system, but can quickly spread through the whole system once the vehicle is driven.

Should the wrong liquid be added, it’s important to first identify the liquid added, and ascertain if it’s a petroleum-based liquid. This can be accomplished by removing a small portion of the liquid, and observing it in a clear container with a little water added in. If part of the fluid separates from the water, it’s petroleum-based.

The consequences of mistakenly adding any amount of petroleum-based product are serious. Many graduates of auto mechanic college will recommend the replacement of any rubber elements in the hydraulics system in this case, including the wheel cylinders, brake valves, and master cylinder, which will become dangerously swollen after contact with this kind of liquid. For other kinds of liquids, an inspection and comprehensive brake fluid flush should be carried out. Ultimately, retaining the wrong kind of liquid can manifest itself in a range of ways—including full brake failure.

Grads of a Mechanic Program Know to Quickly Respond To Brake Fluid Issues

The chemical composition of brake fluid means that its efficiency is dependent on its purity. After several months of use, the percentage amount of water content in brake fluid will generally rise, even in well-sealed systems. Some mechanics will even say that a water content of as little as 4 per cent is enough to undermine efficiency. Even this small change, they assert, can raise the boiling point of brake fluid and cause more incidents of vapour lock, as well as worsen responsiveness. Poorly maintained cars may exhibit brake fluid water content levels as high as 7 per cent.

In this regard, it’s important for mechanics to stress the importance of regularly flushing and changing brake fluid. Doing so forms part of the comprehensive care needed by any vehicle, and will reduce the likelihood of suddenly encountering brake issues that compromise the safety of those in and around the vehicle.

Do you want to do your part in encouraging good auto care and making the roads safer?

One of the most effective ways to realize your goals and become a mechanic is through a professional course with Automotive Training Centres.