Mallory Unilite Distributor Installation How to...

The stock F*rd distributor had been acting up for a long time, and I would have to constantly reset the timing, because the vacuum advance wasn't functioning properly. I chose the Mallory Unilite Distributor with mechanical advance on the advice of a friend at the local speed shop. He had a 401 wag in the 70's, and as it aged and things broke, this was one of the things he replaced and was very happy with.

Before taking the old distributor out, make sure you note exactly where the rotor is pointing, and where the number one plug wire is. Make some sort of mark on whatever is close by, i.e. power steering pump, intake, etc, so that when you install the new distributor there will only have to minimual timing changes.

Once everything is marked, lay the distributor cap off to the side with all the wires still attached. Remove the hold down bolt and retainer, and remove the old distributor. You will need to reuse the gear on the bottom of the shaft. Use a punch to tap out the roll pin, and remove the gear. You will also need to drill a hole in the shaft of the new distributor becuase there were a lot of different gears used through out the years. There is a spacer that goes in between the gear, and the housing. You also have to insert a feeler guage between the spacer and gear before drilling the hole.

I aligned the gear, so that the hole would be drilled parrel to the "blade" on the bottom of the shaft. There was more material around the hole this way. The trickiest part is lining everything up correctly and drilling the hole. I clampe the distributor lightly to the drill press, and shimmed up the shaft end so everything was level. I inserted the feeler guage, and pushed the gear toward the housing. While holding this, I lowered the drill press and used the hole in the gear as a guide. It's only aluminum, so it drilled very easily. With the right size hole drill, just insert a new roll pin and assembly is complete.

Now before dropping the distributor down the hole, look down and see which way the oil pump drive shaft is turned. You may need to insert a large blade screw driver and turn it a bit. When lowering the distributor down the hole, remeber to line the rotor up with the mark you made originally. Have the rotor turned about 30 degrees counter-clockwise from the make when lowering it, because as the distributor gear meshes with the cam gear, it will turn clockwise. Make sure that the gear meshes proplerly with the cam gear, and with the oil pump. You'll know they're not lined up right because it won't go the whole way down in. This took about five or six tries before I finally got it. Once everything meshes, put the hold down back on and tighten the bolt enough so the distributor won't turn easily.

Similar to the old distributor cap, the new one will only fit on one way. Put the cap on, and, with the old one, figure out which one should be the number 1 plug. Once you figure out which one is number one, line the housing up with th number one plug make you made when you took the original out. Then put the cap on, and change the wires over, one at a time, with a wiring diagram handy.

The wiring of the distrubutor itself is very easy. There are three wires. One to the positive side of the coil, one to the negative side of the coil, and one to ground. The original wire hook-ups are not used, and can be disconnected back at the wiring harness. Make sure all of the wires are hooked up correctly, if not, you'll blow the distributor on the first twist of the key. Now that everything is hooked up right, start the engine. I should start easily if all the marks were lined up. If not, a couple of degree rotations, each way between attempts are usually close enought to get it started. Once its started, set the timing to factory specs, and tighten the hold down bolt.

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