Question 1

How to conduct an operating and airtightness check on a brake booster on Mazda 3?

Accepted Answer

To check the operation of the brake pedal press the brake pedal a few times when the engine is off so that no decrease of the distance between the pedal and the frame occurs, then start the engine, in case of the slight movement of the pedal, everything is fine. To check the airtightness, turn on the engine and shut off after one or two minutes, press the brake pedal a number of times loosely, the more the pedal sinks at the first attempt the higher is the probability of the booster being airtight. With the engine running, press the brake pedal and remove the engine with the pedal pressed; in case there is no change in the pedal reserve travel after 30 seconds with the pedal held down, the booster is airtight. Improved tools are needed to dismantle the power unit and is not normally done by the home mechanic; should an issue arise, it is suggested that a new or factory rebuilt unit should be installed. Removal Components The engine cover is removable by lifting it off the mounting posts in the middle and pulling it up at each side. This follows by prying the nuts holding the master cylinder to the booster and then one must carefully pull the master cylinder forward until it slides over the mounting studs, being careful not to bend or kink the brake lines. In 2010 and subsequent models, cut off the brake lines at the brake pipe joint of the firewall which blocks the booster, seal each end of lines and the pipe joint to avoid contamination. First and foremost disconnect the vacuum hose to the power brake booster by pushing the tab and twisting the connection to the battery and unattaching both cables and then unscrew the battery. Take the PCM off the battery tray, and do not disconnect electrical connectors, then remove the battery tray. In the instrument panel, loosen the retaining pin and the washer, and loosen the pushrod on the top of the brake pedal. Installation Reverse the process to remove the booster by taking off the four nuts holding the booster to the firewall, and then carefully raise the booster unit out of the engine compartment. To fit, insert the booster into place and screw the retaining nuts to the recommended torque and join the pushrod to the brake pedal. In case the gasket of the booster-to-firewall is damaged, a new gasket would have to be used. Install the master cylinder and reconnect the brake lines in case they had been removed, and reconnect the vacuum hose. Fill the master cylinder reservoir up with fluid and bleed the master cylinder and the brake system. Lastly, check the functionality of the braking system then subject the vehicle to regular use.

Question 2

Is overhauling the Brake Booster a challenging task that requires special tools and careful reassembly on Mazda RX-7?

Accepted Answer

The process of overhauling the power brake unit is not an easy one and certain tools are necessary to perform the overhaul process that may need to be either manufactured or bought, replacement seals and inner parts may not be readily available and overhauling the power brake unit is also good reason to consider buying a rebuilt unit. In the case of an overhaul, begin by purchasing an overhaul kit with all the required parts to carry the dismantling. Label the front and rear shells so as to reassemble them correctly and measure the range between the lock nut and the end of the fork to set the brake pedal free travel the same. Take off the dust boot and then fasten the power brake unit in the vise with the brake pedal push rod upwards and use the mounting flange to clamp it. The rear shell can be detached by pushing it downwards and clockwise with the aid of long levers on the mounting studs being careful of the spring loaded mechanism. Continue by taking off the spring, air silencer retainer, power piston, valve rod and plunger assembly, diaphragm, valve retainer key, air silencer, filter, and reaction disc, the serrated retainer and bearing of the rear shell. Check and change the rear seal in case it is defective, then take the push rod, flange, retainer, and support plate out of the front shell and check the front seal whether it needs to be replaced. Inspect the power piston and valve rod plunger on any damage and verify that all surfaces are smooth and inspect the two shells on whether they are damaged or not. Invert the unit and reassemble with the new components of the overhaul kit and using a silicone grease to apply to the area such as the valve rod and plunger assembly, reaction disc, diaphragm, and seal lips. Installation of the valve retainer key will place the groove on the valve rod in line with the power piston slot then the rear shell assembly is attached to the front shell by pushing it downwards and counterclockwise until the alignment marks align then fit the power brake unit.

Genuine Mazda Brake Booster

61 Brake Boosters found

Mazda Brake Booster Part Number: KD33-43-640B

Mazda Brake Booster Part Number: KD55-43-640

Mazda Brake Booster Part Number: GSYL-43-80ZC

Mazda Booster Part Number: BDYS-43-80ZB

Mazda Brake Booster Part Number: DGY9-43-80Z

Mazda Power Booster Part Number: VGY3-43-80Z

Mazda Brake Booster Part Number: TDY1-43-80ZA

Mazda Booster Part Number: BCYA-43-80ZC

Mazda Power Booster Part Number: VCY8-43-80Z

Mazda Booster Part Number: BJY3-43-80Z

Mazda Brake Booster Part Number: DFY1-43-80Z

Mazda Brake Booster Part Number: NFY7-43-80ZA

Mazda Brake Booster Part Number: CCY9-43-80ZC

Mazda Brake Booster Part Number: NAYJ-43-80Z

Mazda Brake Booster Part Number: GJY2-43-80ZB

Mazda Brake Booster Part Number: FEY1-43-80ZA

Mazda Brake Booster Part Number: EGY3-43-80ZA

Mazda Brake Booster Part Number: CGY5-43-80Z

Mazda Brake Booster Part Number: DBZ2-43-80ZA

Mazda Brake Booster Part Number: BPYL-43-80ZE

Mazda Brake Booster

Mazda Brake Booster Parts and Q&A

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