My car is a 61 Mk2 2.4. I have no spark. Replaced points, coil (sport coil). wires, cap & rotor. There is power at the coil (wire from distributor) and the resistance is appropriate. There is no spark at points. Screw in type wires so I can't easiiy check for spark off the coil without out using a different HT wire, but it's new. Only nor replaced is the condensor. I'm thinking a short in the distributor itself...
Did you get the plastic insulator around the screw that holds the points to the distributor? You can check with a multimeter, with the points open there should be open circuit between the spring on the points and the distributor body.
Have you checked your ignition fuse?
Does the car crank over but not start if you push the button on the dash?
Change the condenser/capacitor.
Is the car still positive earth?
EDIT: And JB is dead accurate about that insulation piece.
Some bad rotors out there with rivet that discharge to the shaft instead of the cap.
Genuine NOS Lucas ultrasonically welded rotor. Holden sells a reasonable facsimile
Did you have a spark before you replaced all that stuff ? All the points do is earth the coil. Then, by breaking the current flow through the coil when they open, cause the coil to generate a spark. So if you've installed the points incorrectly this make/break action will not have any effect.
I agree with the probable diagnosis of a short in the distributor due to the lack of the plastic insulator.
What also concerns me is the failure to replace the condenser. That is a critical component in the ignition circuit. It is not there to "protect the points" as some people believe.
The condenser and coil make up a series bell ring circuit.
When the points open the coil discharges into the condenser The condenser then discharges into the coil and then the coil discharges again into the condenser and the cycle continues until it runs out of energy
All this happens in milliseconds (thousandths of a second) and if seen on a cathode ray oscilloscope many cycles take place in each spark
Condensers do lose capacity as they age, and the dielectric dries out. You can have the best sports coil ever made but if the condenser is on its last legs you won't get a decent spark.
Cheers
the spark circuit has two ends. the battery at one end and the sparkplug at the other. start at the halfway point and eliminate the working half as a possible source of the problem with each test. with no more than three or four tests you should be able to find the culprit.
So I lost spark one morning.and decided I wpoi;d dp spme long overdue maintenance, It's been about a month so, to be honest, I can't remember if I changed the points (I know I have changed them in the past year) or just re-gapped them. The condensor was also changed in the past year. I never changed the wires. cap. rotor. or coil in the 12 years I've owned it, so I figured it was time. The newere rotor body has a different shape, but they appear to be the length & width
I appreciate all the help and I will check what you have suggested. I did think about the insulator on the points' post as it is clear and difficult to see,
I have gone over several things and still stumped:
Points clean and properly gapped
Condensor new and tested good
12 Volts to the coil and proper resistance in coil
Ground wire in distributor good
All wires, cap & rotor new and good as best I can tell
Rotate the engine until your points are open (on one of the lobes), disconnect the wire from the spade terminal on the side of the distributor, next take your multi metre and do a continuity test from the spade terminal arrowed in RED to ground _ there should be no continuity.
If there is, the braded wire inside the distributor is shorting or you have not mounted the points correctly with the plastic washers on its mounting stud.
Also check if there is continuity from where the coil hooks up to the spade terminal on the side of the distributor to the end of the terminal of the braded wire where it connects onto the mounting post.
Sometimes the braded wire may look like it's crimped into its terminals properly, but maybe not.
Without checking, I believe there is also a fibrous washer at the bottom of the mounting stud to keep the points return spring isolated from ground.
At any rate, if you perform my test in the first paragraph, that will tell you if you have things mounted correctly.
Other obvious things like making sure you have 12 volts to the coil with the key on, check with a test light or the voltage setting on your metre, just to make sure.
Make sure that ground wire is actually grounding the base plate and do a continuity test there.
Check that the braded wire from the spade terminal on the side of the distributor is not grounding out somewhere.
Current flows through the braded wire, through the closed points, saturating the coil with 12 volts, when the points open, that's when you get spark.
When the points open, the magnetic field in the coil collapses, inducing a voltage on the secondary windings creating spark at the plugs, depending on where the rotor is.
I'm curios too, how are you testing the condenser ?
Here's a video, but it's pretty shitty, but at about 3:50 minutes it shows an insulating plastic washer with a shoulder at the bottom.
I've come across fibrous washers here as well, as mentioned above.
If you watch the whole video, he wraps the hot braded wire around the condenser wire, I don't agree with that, it has to move freely when the vacuum advance moves the base plate.
if you're getting 12V too to the coil and not just out of the distributor, then it is very unlikely that there is anything wrong with the points or capacitor. after all, that half of the distributor (the part that sends 12V to the distributor) serves the coil only and if you're gettting 12v to the input side of the coil you need look no further upstream for your problem. you have to test the big black wire OUT of the coil that goes back to distributor. to do that i would pull that wire off the distributor and lay it near the engine block and look for a spark there. if none, then your coil is most likely bad, despite tests.
UPDATE! Fit a piug directly to the secondary coil wire that runs to distributor cap. Grounded the plug on the engine block NO spark. Power to coil and good resistance through the coil so I removed the ground wire on the coil (runs between coil & distributor) and again grounded plug attached to secondary wire from coil. When I ran a separate wire to from the ground terminal of coil to engine to ground, there was spark. Coil is good. Wire from coil to side of distributor has continuity as does the ground wire (red) in the distributor that leads from the points post to under the plate. Gotta be a grounding issue somewhere in distributor.
Have you checked the ground strap that jumps from the body across the LHS engine mounting?
If it's still OK remove it and clean up contact with body & block. (LHS sitting in the car looking forward)
Losing ground inside the distributor is most unlikely if all wiring is sound/fine.
...just a matter of time now. tally ho!