Daily drivers, weekend warriors, or even full-race trim vehicles require regular system and component maintenance to ensure reliability and safety. Engine oil, coolant, transmission
fluida vehicle’s fluids all have a life expectancy, which must be respected and monitored. This is especially true of the brake system, considering it’s the viability of the brake fluid among others that allows the vehicle to continue slowing down when needed.
Brake fluid endures vast cycles of heat and load so it’s important to check the brake fluid level or flush out the entire system. The high boiling point of brake fluid wicks away heat from the brake system but also prohibits vaporizing in the lines. Since vapor is compressible, you can see why it’s important the brake fluid never gets to this point. It’s the fluid’s push into the calipers or wheel cylinders that activates the pads or shoes. If left untouched, old brake fluid can also retain moisture, which corrodes internal brake parts over time. A neglected system requires more distance to stopor could lead to a total brake system failure.
To illustrate bleeding the brake system, we found a daily driven ’67 Camaro that had just been upgraded to a four-wheel power disc setup. Its brake fluid had not yet been checked or flushed. The crew at Lou’s Performance in Sun Valley, California, began work by getting the car on a lift and removing the tires to give you a better view. The best part is that the job only took us about an hour to complete and can even be done in the garage with basic tools.
1. As with any maintenance,...
1. As with any maintenance, the first step is checking the vehicle systems. We pulled the lid off the master cylinder to check the level. If the level is low, there could be a leak in one of the lines. At this point, it would be wise to locate the leak before bleeding the system.
2. Since our system was free...
2. Since our system was free of leaks, we went ahead and pumped out the old brake fluid. Then we topped off the master cylinder using Wilwood’s Hi-Temp brake fluid (PN 290-6209). The lid was then installed to pressurize the system when pumping the brakes.
3. A critical step in bleeding...
3. A critical step in bleeding the brake system for fluid is to begin with the corner of the vehicle farthest from the master cylinder. For us, that was the passenger rear disc brake. Using a self-bleeder tool, we attached the rubber boot to the nipple on the rear of the caliper and created an airtight seal.
4. Using a 10mm open wrench,...
4. Using a 10mm open wrench, we loosened the nut. Then we began to pump the brake pedal inside the car. The action of the brake pedal pushes the old fluid out of the line and into the container. From there, we tightened the 10mm nut, removed the rubber boot, and moved onto the left rear caliper.
5. At the left rear caliper,...
5. At the left rear caliper, we again attached the rubber boot to the nipple at the rear of the caliper. We then loosened the 10mm nut, pumped the brake pedal to push the old fluid out, and tightened the nut again.
6. In the meantime, it’s important...
6. In the meantime, it’s important to constantly check the level of brake fluid in the master cylinder. We checked the level after each caliper was bled, added more Wilwood fluid, and reinstalled the lid.
7. Working our way forward,...
7. Working our way forward, we used the same method and bled the brake line on the passenger side.
8. The driver side is the...
8. The driver side is the last caliper to bleed. After topping off the brake fluid again, we installed the boot over the nipple, loosened the 10mm nut, and pumped the brake pedal to release the old fluid into the container.
9. The last step involves...
9. The last step involves double-checking that all the brake bleed nuts are tight. Then, we again refilled the master cylinder to the top. From there, the brake system was ready to perform. CHP