What to do if the Baojun 730 brake master cylinder is still leaking after replacement?

[TimothyAnn]

If the Baojun 730 brake master cylinder is still leaking after replacement, it may be due to a fault in the vacuum booster pipe or the vacuum booster itself, which is unrelated to the brake master cylinder. It is necessary to visit a repair shop or 4S store for inspection. The main function of the brake master cylinder is to provide brake assistance, which only takes effect after the vehicle's engine is started. Symptoms of a faulty brake master cylinder include: 1. Oil leakage at the connection between the brake master cylinder and the vacuum booster or at the limit screw. 2. Poor or ineffective braking even when the brake pedal is fully depressed. 3. The brake pedal feels too soft when pressed. 4. The vehicle pulls to one side after braking. 5. Sudden brake failure. 6. The brake pedal does not return or returns slowly.

[Preston]

As a mechanic who frequently works on brake systems, I've handled many similar cases. If the master cylinder replacement still results in air leaks, it's usually not the master cylinder itself but other installation issues. Possible causes include loose or cracked tubing connections (e.g. improperly tightened copper pipes/rubber hoses allowing air escape), or faulty wheel cylinders - especially with rear drum brakes or worn front calipers. Contamination during installation (uncleaned grease residues or reused old parts) may also compromise sealing. Air leaks cause spongy brake pedals, creating driving hazards. My recommendation: First inspect all connection points for hissing sounds or perform a soapy water bubble test to locate leaks. If unresolved, seek professional repair immediately. Safety comes first - new parts don't guarantee problem resolution, thorough troubleshooting is essential.

[ArcherMarie]

I've been driving for over a decade and once encountered a situation where the master cylinder started leaking air right after replacement. It took me quite some time to fix it. Turned out to be either an unnoticed aging crack in the brake line or the worker not tightening the screws properly during installation. Don't panic in your situation - first recall whether the installation process was carefully inspected, as it might just be a loose connection or worn wheel cylinder. Air leaks can cause brake failure, which is extremely dangerous. I suggest you try listening for hissing sounds from the brake pedal to locate the leak, or visit a nearby repair shop for quick diagnosis. Don't rush to spend money on new parts - it might just be a minor issue. After repair, remember to maintain your brake system regularly to prevent future problems. Make it a habit to inspect the brake lines regularly - it saves trouble, money, and most importantly, keeps you safe.

[Xavier]

If the master cylinder is replaced and there's still air leakage, you must stop driving immediately. Air leakage can cause complete brake failure, leading to accidents in extreme cases. This is not a minor issue. If the master cylinder is fine, it could be loose pipes or a faulty wheel cylinder. Check all connections to ensure they're tightened, and listen for any air leakage sounds or look for oil stains. I strongly advise against handling this yourself; instead, call a tow truck to take the vehicle to a professional repair shop. It might be due to incorrect installation or misaligned parts, and a mechanic will use professional tools to test it. There's no room for negligence in the brake system. After repairs, have the technician conduct a thorough inspection to ensure safe driving.

[VeraFitz]

As a car owner, I've also experienced air leaks after replacing the master cylinder. Don't rush to spend money on new parts—it could just be a minor issue. First, check if the pipe connections are loose or rusty and try tightening them. Then, inspect whether the brake calipers are worn or leaking. Leaks often occur if the installation wasn't clean or old parts were reused. I suggest asking a friend to help press the brake pedal while you listen for the leak, or spend a little money at a local shop for a quick check. If you really want to save money, start with small fixes, but avoid driving fast until it's repaired. Air leaks affect braking distance, so safety comes first. Regular maintenance of the pipes to prevent aging can save you a lot of trouble.

[StCarmen]

From a technical perspective, air leakage after replacing the master cylinder usually stems from pipeline leaks or issues with the wheel cylinder. The brake system operates on air pressure, and even a small hole in the pipeline can cause air to escape; wear on the wheel cylinder can also lead to seal failure. It might be due to improper pipeline alignment during installation or the use of damaged components. I recommend applying soapy water to the joints to test for leaks or using a pressure gauge to check for pressure loss. Air leakage can cause sluggish brake response, which is extremely dangerous. It's crucial to visit a repair shop immediately for a comprehensive inspection, and if the wheel cylinder is faulty, it needs replacement. Regularly monitor the brake fluid condition and keep the pipelines clean to prevent aging-induced leaks. After repairs, conduct a full functional test to ensure everything is in perfect working order before hitting the road.