Carburetors were in widespread use on vehicle engines before the advent of fuel injection systems now used on most vehicles. A carburetor provides the correct fuel-to-air ratio to the intake manifold for smooth and efficient engine operation. Holley is an American company that has been manufacturing fuel systems for vehicles since the early 1900s. The Holley 670 carburetor is a "bolt and go" design intended, according to the manufacturer, for "serious street enthusiasts."
Instructions
- 1
Open the hood. Loosen the wing nut on the top of the air cleaner assembly mounted on top of the present carburetor. Make a note of the location of the vacuum lines attached to the air cleaner. Pull the vacuum lines straight off the assembly. Lift the air cleaner assembly straight up and remove it from the engine bay.
2Loosen the fuel line fitting on the carburetor with a tubing wrench. Place a rag under the fitting to catch fuel that may be spilled when the line is removed. Pull the fuel line off and push it slightly to the side so as to not impede the removal of the carburetor.
3Make a note of any vacuum lines attached to the carburetor and pull them straight off. Pull the hose from the PVC valve straight off the carburetor. Pry the retaining clips off the choke rod and throttle and kick-down linkages with a flat-blade screwdriver. Remove the rod and linkages from the carburetor.
4Remove the four retaining nuts from the base of the carburetor with a wrench. Lift the carburetor straight up and remove it from the engine bay. Scrape any gasket residue from the carburetor mounting surface on the intake manifold with a gasket scraper. Do not let any gasket material or residue fall into the intake manifold opening.
5Line up the holes on a new carburetor gasket -- included with the carburetor -- over the carburetor mounting studs on the intake manifold and lower it into place. Line up the mounting holes in the carburetor with the mounting studs and lower it onto the gasket and the intake manifold. Ensure the connection for the throttle linkage on the carburetor is facing the rear of the engine bay.
6Thread the retaining nuts on the threaded ends of the carburetor mounting studs and tighten them in a criss-cross pattern to between 60 and 80 foot-pounds with a torque wrench.
7Connect the choke rod and the throttle and kick-down linkages in the reverse order of removal. Depress the accelerator pedal all the way to the floor and release it. Do this several times while a helper is observing the throttle linkage to ensure it is not binding.
8Reconnect the fuel line to the carburetor and tighten it with a tubing wrench. Push the vacuum lines into the fittings on the replacement carburetor that correspond to the old carburetor.
9Lower the air cleaner assembly onto the top of the carburetor so that the protruding mounting stud protrudes through the hole in the lid of the assembly. Tighten the wing nut on top of the air cleaner. Push the vacuum hoses back into their fittings on the air cleaner until they are fully seated.
