How to Repair Holley Carburetors
- 1). Disconnect the carburetor from the engine by using a pair of pliers to pull the throttle cable and choke cable (if your vehicle uses a manual choke) from their respective brackets. Pull the hose clamps slightly down each fuel and vacuum line and remove each line by hand, ensuring to not tear the line. Unbolt the corner "ear" bolts from the base of the carb with a socket wrench set. Remove the air filter assembly by unscrewing the wing nut on the air filter cap by hand. Pull the cap, filter and filter base off the carb's choke tower.
- 2). Place the carb in a wash tray and thoroughly spray the exterior and interior holes with carb cleaner spray.
- 3). Remove the fuel bowl(s) bolts, one on each corner, with a socket wrench. Pull the bowl(s) away from the metering block(s) and discard the two gaskets that seal the bowl to the metering block. Unscrew the two main jets (one set per metering block) and inspect for damage and debris. Replace the jets if necessary,with the same size, indicated by the number stamp on the jet head. Unscrew the corner screws from the metering block(s) and pull the block assembly from the main body of the carb. Discard the gasket and unscrew the power valve from the back of the metering block with a box wrench.
- 4). Place the carb on its head and unscrew the base plate screws. Pull the base plate off and match the old base plate gasket with the correct replacement from the rebuild kit. Place the new gasket in place and reinstall the base plate. On the base plate gaskets, you may use thread locker to ensure the screws remain tight.
- 5). Spray all interior components of the carburetor with compressed air and carb cleaner, ensuring all debris, grime and fuel residue is removed.
- 6). Install the new O-ring and power valve in the back of the metering block(s), and press the block assembly against the main body with a gasket sealing the seam. Tighten the screws, securing the metering block(s) to the main choke tower. Insert the main jet set(s) into their holes adjacent to the PVC (power valve cavity) in the center of the metering block and tighten them with a flathead screwdriver.
- 7). Place a new metering block gasket on the face of the metering block(s) and press the fuel bowl(s) against the metering block(s). Tighten the four corner bolts of the fuel bowl with a torque wrench, to 8 foot-pounds. This completes the repair process on the carb, so you can now reinstall the carb on the engine. Place the carb's base plate on the intake manifold's mounting surface. Tighten each ear bolt until it's snug. There is no need to over-tighten these bolts, as you may risk cracking the main body of the carb. Attach each fuel and vacuum line, ensuring that each hose clamp is brought over the connection port of each hose, securing them to the carb's body. Insert the cables for the throttle and choke assembly and ensure that the brackets are tight, using a screwdriver to tighten the cable bracket if necessary. Place the air filter assembly on the top of the choke tower and tighten the wing nut by hand.
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