STUMPED AND STUMPED AGAIN

[80spit]

This is weird.

The Problem is no spark at the points sometimes or I sould say at one side of the points. The side inside by the cam doesn't seem to get the spark from the outer contact of the points.

I have replaced coil, points, condenser, H/T lead, L/T lead, distribuitor ground wire, rotor button and dist cap.

I have lots of voltage to outer contact of the points 12.5v and spark on one side of points, I can ground that side of the points and get spark, but when I crank the engine I get no spark at the points.

I have checked all connections and the funny thing is when I have no spark I still have voltage to all connections.

Would the vacuum advance be a factor here? It dosent move when I apply vacuum to the hose.

 

[AltaKnight]

Are you sure you have all those plastic insulator bits and washers properly assembled in the correct place and order. If you have the coil wire disconnected then with an ohmeter you can check that the points are alternately grounding and opening as the distributor rotates. The only other thing I can think of is that you have a bad condenser there.

 

[TR3driver]

The side of the points nearest the cam is supposed to be grounded at all times. Have you checked that it is indeed grounded ? Eg, no voltage there when the points are closed and the ignition is on ?

If so, I think you must have grease on the face of the points, or else the gap is too wide. With the points closed, you should find ground from the fixed contact, all the way out to the coil "-" terminal.

 

[hondo402000]

buy a pertronix system and drive!

 

[RonMacPherson]

Or buy a Crane and never have to use Pertronix replacements. again.

 

[eschneider]

I have lots of voltage to outer contact of the points 12.5v and spark on one side of points, I can ground that side of the points and get spark, but when I crank the engine I get no spark at the points.

not sure about your car, but on some, the power supply for the ignition system is different when the key is in the 'start' position, vs. when the key is in the 'run' position.

do you have 12v at the coil when the key is in the 'start' position? if not, and it goes to 12v in the 'run' position, there is something amiss between the coil and the 's' terminal on the starter solenoid.

 

[piman]

Hello 80,

you shouldn't see a spark at the points when you crank the engine. With your voltmeter on the negative side of the coil turn the engine by hand (Make sure the distributor cap is off in case it kicks)and you should see the voltmeter go from approximately 12 volts to zero and back to 12V. If it stays constantly at 12 volts there is something wrong with the way the points are assembled, or set or they are contaminated as someone suggested.
Forget the vacuum advance, that is irrelevant. If you get a lower voltage but nowhere near zero it is likely that the points are contaminated and\or the earth lead inside the distributor is broken.

By the way, electronic ignition is unneccessary and a waste of money.

Alec