Genuine Chevrolet Nova Brake Master Cylinder

Chevrolet Nova Brake Master Cylinder Parts Questions & Experts Answers

• CYLINDER
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  Q: How should one properly overhaul a master cylinder on Chevrolet Nova?

  A: Do not yet proceed with the brake master cylinder overhaul, but research whether a new or factory rebuilt brake master cylinder is available, and can be purchased at a reasonable price. In addition, check for the availability of the rebuild kit. It is good to lay some rags across the Brake Line fittings and have caps or plastic bags to put over the ends of the line once disconnected. Remember brake fluid is a strong stain and tends to mess with paint. Un-thread the tube nuts on the ends of the brake lines, where they are connected to the brake master cylinder, with a flare-nut wrench, in order not to round off the flats of these nuts. Pull back the brake lines slightly and plug the ends to prevent them from getting dirty. On manual brakes, you shall remove the pushrod at the brake pedal within the car and also the two brake master cylinder nuts. If there is a bracket retaining the combination valve, pull the valve forward slightly without distorting the hydraulic lines and remove the brake master cylinder from the car. Empty the reservoir also by removing the cover, and the diaphragm as well if there is still little fluid in the tank. Remove all the fluid from the brake master cylinder and then put the brake master cylinder in a vise and place wood on all sides of the cylinder. In the manual type, pull out the retaining ring around the pushrod and next is to take out the secondary stop bolt which is located either in the front of the fluid reservoir or on the underside of the brake master cylinder body. The retaining ring will be removed from the groove and the primary piston assembly will be pulled out of the brake master cylinder and so is the secondary piston, spring and retainer where inverting the brake master cylinder and tapping it on a block of wood may be necessary. There may be scoring or wear on the inside surface of the brake master cylinder and on the secondary piston and in this case, the entire brake master cylinder must be replaced. Light honing is allowed only if the bore is well maintained. Light honing according to Section 5 is allowed only if the bore is in good condition. Clean and blow all parts with brake system cleaner; dispose of any rubber items and the primary piston and get a rebuild kit for replacement parts required. Check the line seats in the brake master cylinder body; if worn out replace them by striking them out with a screw and obtain a new brake line nut to fit new ones in place. Install new second seals into the grooves of the second piston, put primary seals and seal protector over the end of the second piston; then grease the cylinder bore and second piston with fresh brake fluid. Assuming correct assembly from right of tool, insert the spring retainer into spring. Pull both over the end of the secondary piston to place retainer inside primary seal lips. With the brake master cylinder vertical, push the secondary piston into the bore completely: then put the brake fluid on the seals on the primary piston: then fit it into the cylinder bore and while the retaining ring is put into place hold down the primary piston. Go on screwing in the stop screw while still holding down the piston; then fit the reservoir diaphragm into the reservoir cover plate, where it should be fully inverted inside the recess lid. Any time the brake master cylinder is removed, the entire hydraulic system must be purged, and this may be done more quickly by filling the brake master cylinder and bench bleeding it before reinstalling. During bench bleeding, screw the threaded plugs into the cylinder outlets, pour brake fluid into the reservoirs and tilt the brake master cylinder to avoid drippings. Open one plug at a time and then using force push in the piston assembly further into the bore to expel air and replace the plug before allowing it to retract again. With each outlet, pat the piston a few times to ensure that all the air has been cleared out of the cylinder; other methods include using a finger to block the hole instead of using the plug after each stroke. After that, blow only brake fluid and once only brake fluid is ejected the plug should be replaced and go to the next port. Fill the brake master cylinder reservoirs, fit the diaphragm and cover assembly, the reservoirs should only be filled to the top of the divider to avoid spilling over. Last but not least, place the brake master cylinder back in its rightful position with equal and correct measures followed in the removal process then, bleed the brakes.