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How to Install a Dual-Point Distributor [by: dmorris1200]

The first thing you want to do is get your engine to the TDC #1 cylinder.

Then, get your timing mark to 0 and lift up the distributor cap. The rotor should be pointing to where the #1 plug wire is in the cap. If it's opposite, you're 180 degrees out, and you need to rotate the crank one turn.

Now that you're on TDC for the #1 cylinder, mark where your rotor is pointing so you can make sure the new one faces the same direction.

Remove the distributor primary wire that goes from the distributor to the negative terminal of the coil. Remove the vacuum advance line and make a mental note of where the advance chamber is facing.

Remove the hold-down bracket and remove the distributor. The rotor will move slightly while removing the distributor -- note this movement for installing the new distributor.

Once you have the new distributor in and the rotor facing the same way as the old one, and the vacuum advance chamber facing the same way, install the distributor cap and install the #1 spark plug wire in the terminal that the rotor is facing. Then, work your way around, swapping over the rest of the wires from the old cap.

Now it's time to set the points. Remove the cap and rotor, loosen the hold-down, and rotate the distributor housing till one set of points opens. Tighten the hold-down, and rough-set the gap to manufacturer specs with a non-metallic feeler gauge. In a pinch, I have used a piece of a matchbook cover to rough-set points.

After the first set is adjusted, rotate the distributor housing again until the other set opens, and repeat the rough set procedure.

Now, install the rotor and rotate the housing back to the original location so that the #1 wire is over the rotor with the cap installed. Connect the primary wire to the coil and start the engine. With the vacuum advance disconnected, set the base timing to manufacturer specs to get the engine running stable enough to set proper dwell.

Shut off the engine and hook up a dwell meter to the negative side of the coil and the battery ground. What you need to do is check the dwell for each set of points individually.

What I usually do is stick a piece of matchbook cover in one set of points to disable them while setting the other set. It's time consuming, as you need to start the engine after each adjustment to recheck the dwell.

When you get the dwell to the correct setting, disable the points you just set and follow the same procedure for the other points. Once your dwell is all set, then you need to reset your base timing, as any dwell change will affect base timing.

Now, reconnect the vacuum line to the vacuum advance chamber and you're ready to check total advance to make sure it matches the specs given by the distributor's manufacturer. And let's not forget the best part, the test drive.