Posted by HH56 On 2019/5/11 15:59:32

If the points are new they should be OK but if they are the old points they might have developed an oxidized coating on the contact surfaces from sitting over the years and are not making good contact. A light touch up with a contact burnisher or point file might be in order. To set the gap, bump the engine until the block that rides on the distributor cam and opens the points is sitting on a high spot on the cam. Use the feeler gauge and adjust the gap until the proper amount is measured and then tighten the screw. If they are new points don't forget to add a very TINY amount of grease smeared onto the cam surface.

There is a wire in the distributor between the points and the outside terminal that is covered with a fabric material or cloth like insulation. When working inside the distributor if the wire is moved the fabric can be rotten and fall off letting the wire short and that would result in no spark.

Verify the voltage to the coil. If it has the correct starter solenoid, when the key is turned on there should be 7-8v on the coil terminal with the pink wire coming from the ballast resistor. If the points are open, that same voltage should be on the terminal going to distributor and if the points are closed or something has shorted in the distributor, very close to 0v on that terminal. When the points are closed if the voltage is higher than about .3 or .4 volts then a good solid ground to the distributor or oxidized and dirty points is suspect.

When the starter is engaged that 7-8v coil supply should change to 12v as long as the starter is turning. If the 7-8 volts is missing the ballast resistor or ignition switch is suspect and if it doesn't change to 12v when the starter is cranking either the starter solenoid has been changed to an ordinary 3 terminal solenoid or a wire is broken or disconnected.

To rule out the rotor or cap as the cause of no spark to the plugs remove the center wire from the cap and position the end near the block. As you crank the engine the spark should be visible as multiple sparks of bright blue color jumping from the wire to the block. If you see nothing, remove the small black wire between the coil and distributor from the distributor terminal and scratch it on the block. As you observe the HV wire, there should be a spark each time the connection you make to the block is broken. There can be a back voltage that can be significant so don't hold the small black wire in a way that you are touching the terminal as you make and break the connection to the block.

If you have spark from the center wire but not at the plugs when things are connected properly then the rotor could be the wrong one or if the type with a resistor, possibly have an open resistor.