Where do the vacuum lines go on a Quadrajet?

If you have an electric chock, ther is usually a vacuum port on the choke tha runs through hard lines to the exhaust crossover in an OEM manifold, but otherwise, you can run a line directly the the port on the top rear pass side port on the carb air horn.

Does a Quadrajet have vacuum secondaries?

The Quadrajet has mechanical secondaries, which open promptly when you mash the gas. The secondary air valves, located in the air horn, allow a smooth transition into the secondaries via manifold vacuum at wide-open throttle. All employ air valve transition into the secondaries.

What do carburetor vacuum lines do?

In many cases, you will also find vacuum ports on carburetors and throttle bodies. Since it isn’t feasible to attach most accessories and components directly to an intake manifold, vacuum hoses essentially “transmit” vacuum from the manifold to wherever it is needed.

How do I identify a Rochester quadrajet?

All Rochester Quadrajet carburetors are identified by a seven- or eight-digit GM part number. On units made before mid-1968, the part number was stamped around the outside edge of a round metal tag attached to the fuel bowl.

Is a quadrajet carb good?

A lot of good and bad has been written about the use of a Rochester Quadrajet carburetor as a replacement four-barrel. Some enthusiasts love them while others avoid them like the plague. The truth is, a properly tuned Quadrajet can be just as efficient and reliable as a bolt-on substitute performance carburetor.

What are the signs of a vacuum leak?

Here are four signs that your vehicle has a vacuum leak.

• Sporadic Idling. A vacuum leak introduces excess air into the engine, and this directly affects how your engine runs.
• Engine Hesitation. Your engine trouble will not be limited to your idling if you have a leak.
• Vacuum Sounds.
• 4 Check Engine Warning.

What happens if you disconnect vacuum advance?

Feared by many, and ignored by many more, the vacuum advance can is an important component of your ignition platform that offers both performance and economy. Leaving it unplugged is akin to throwing free engine efficiency straight down the drain.

What are the two hoses on a carburetor?

The two hoses circled in red are vent/over flow hoses. Should not have any plugs in them. They basically both route between the two carbs, hanging down. Each carb has a vacuum nipple.

Where are the vacuum ports on a Quadrajet?

Mar 30, There are more vacuum ports on the Quadrajet then on the Instead of trying to find a vacuum line for each port on the carb to attach to.Oct 03, · my vacuum advance is fed from the front of the carb via a steel and rubber line. the T: right goes to the Brake booster. left (steel line) goes to kickdown.

What should I do if my Quadrajet carburetor is leaking?

Look for any fuel restriction – check for kinks in the fuel line. Replace any fuel filters – There is usually one in the fuel inlet of the carburetor and often there will be an in-line fuel filter. Vacuum leak – Use spray carburetor cleaner and spray around the base of the carburetor and any vacuum lines.

How many hoses are in a Quadrajet vacuum line?

Oct 15, · I know what the stock diagrams show, Quadrajet Vacuum hose routing. I know what the stock diagrams show, That switch had like 5 hoses going to it. A ported vacuum source, a manifold vacuum source, a line going to some switch on the rear of the carb, a vacuum advance and some crazy vacuum retard.

Do you need a diagram for a Quadrajet?

Mar 25, · News: As of April 1, All Classified forums require a Site Supporter subscription. I have a new quadrajet for my truck and need vacuum diagrams. Also look on your radiator support for the silver looking decal / diagram that displays vacuum lines / routes.