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Tue Aug 06, 2019 6:39 pm

I'm running points/condensor and have no spark at the points. Coil has power going to it on + side.

Car ran great until about 5 mins ago. It was idling and then flat out died. I've narrowed it down to spark.

Not having power to the points would be the condensor correct?

All connections at coil are correct (it was running before) and in good shape. I tested for voltage at the + wire and it had like 12.5 volts.

I have to walk to go and get it and I leave town the day after tomorrow so I don't have much time. I have an extra coil but wanted to make sure it wouldn't likely be something else.

Tue Aug 06, 2019 6:42 pm

Did the points slip and close the gap?

Tue Aug 06, 2019 6:49 pm

Glenn wrote: Did the points slip and close the gap?

No they still have the proper gap. I should have mentioned that.

I checked for spark at the end of the spark plug wire (no spark). Then I checked for spark at the points with the rotor off and had a helper turn the key. No spark but had .016" gap still. So I checked for power to the coil and there's power coming out of the + wire coming from the vehicle. I checked continuity at each end of the wire going from the neg side of the coil to the condensor and the connection is good.

Tue Aug 06, 2019 6:50 pm

Can the condenser be shorted and grounding the points?

Tue Aug 06, 2019 6:57 pm

Glenn wrote: Can the condenser be shorted and grounding the points?

Dang I didn't think of that. It's a 009 with sorta a double spade connection to make it from the outside of the distributor to the inside. There's an insulator but it's kinda loose. It would be shorting out to the distributor body though, I realize the points attach to it but just wanted to be sure it would have same effect.

So what I'm thinking based on your responses is if the coil was bad the points should still spark? I'll bring my spare coil just incase and I'll take a look to see if the condensor could be shorting out.

Tue Aug 06, 2019 7:51 pm

It might help if you understand two basic concepts of the points and condenser:
1) The points are a simple contact switch. When the points are CLOSED the point wire is grounded to the body of the distributor. When the points are OPEN the point wire is OPEN and not connected to ground.

2) While the condenser has a single wire and is grounded to the body of the distributor... there is no path for current to flow from the wire to the body/ground. If the condenser wire actually grounds to the body of the condenser... it is failed and needs to be replaced.

Try this test:
Remove the distributor cap and rotate the crank pulley until you can see that the point contacts are CLOSED.

Remove the point/condenser wire from the #1 terminal of the ignition coil.

With a continuity tester or ohm meter, test the points wire for resistance to ground. With the points closed, there should be ZERO resistance to ground.

With a plastic or wood "stick" push the points are to OPEN the contacts. The resistance between the points wire and ground should change to INFINITE. This confirms the points+condenser are NOT shorted to ground. If opening the point contacts makes no change... you points or condenser are shorted to ground.
Remove the points from the body of the distributor and wrap it in a rag so it cannot touch ground. Re-run the test. If the points wire now shows INFINITE resistance when the points are OPEN... the short is inside the condenser. Replace it.

Once you confirm opening/closing the points changes the resistance to ground for the points wire...
Reconnect the points wire to the coil #1.
Remove the center HT wire from the center of the distributor cap and hold the exposed conductor near a ground.
Turn the ignition switch ON.
As you open the point contacts, look for a spark to jump from the tip of the HT wire to ground.
Allow the point contacts to close again and then OPEN the points. Another spark should jump from the HT wire to ground. This spark should be white-blue and should be able to jump at least 1/2" or more.

FYI, one of the functions of the condenser is to minimize the spark at the point contacts. This extends the life of the points before they get pitted. So looking for a spark AT the point may not always be a legitimate test. Testing for continuity thru the points is a valid test as the points are a simple OPEN/CLOSE switch.

Tue Aug 06, 2019 7:58 pm

ashman40 wrote: It might help if you understand two basic concepts of the points and condenser:
1) The points are a simple contact switch. When the points are CLOSED the point wire is grounded to the body of the distributor. When the points are OPEN the point wire is OPEN and not connected to ground.

2) While the condenser has a single wire and is grounded to the body of the distributor... there is no path for current to flow from the wire to the body/ground. If the condenser wire actually grounds to the body of the condenser... it is failed and needs to be replaced.

Try this test:
Remove the distributor cap and rotate the crank pulley until you can see that the point contacts are CLOSED.

Remove the point/condenser wire from the #1 terminal of the ignition coil.

With a continuity tester or ohm meter, test the points wire for resistance to ground. With the points closed, there should be ZERO resistance to ground.

With a plastic or wood "stick" push the points are to OPEN the contacts. The resistance between the points wire and ground should change to INFINITE. This confirms the points+condenser are NOT shorted to ground. If opening the point contacts makes no change... you points or condenser are shorted to ground.
Remove the points from the body of the distributor and wrap it in a rag so it cannot touch ground. Re-run the test. If the points wire now shows INFINITE resistance when the points are OPEN... the short is inside the condenser. Replace it.

Once you confirm opening/closing the points changes the resistance to ground for the points wire...
Reconnect the points wire to the coil #1.
Remove the center HT wire from the center of the distributor cap and hold the exposed conductor near a ground.
Turn the ignition switch ON.
As you open the point contacts, look for a spark to jump from the tip of the HT wire to ground.
Allow the point contacts to close again and then OPEN the points. Another spark should jump from the HT wire to ground. This spark should be white-blue and should be able to jump at least 1/2" or more.

FYI, one of the functions of the condenser is to minimize the spark at the point contacts. This extends the life of the points before they get pitted. So looking for a spark AT the point may not always be a legitimate test. Testing for continuity thru the points is a valid test as the points are a simple OPEN/CLOSE switch.

Cool thanks, an easy test. I was just reading up on how they worked. I understand the points part but didn't fully understand what the condenser did. It makes sense that if the condenser wire is contacting the distributor body that would make a route of less resistance instead of going the way it was suppose to.

Electricity is so lazy always has to go the route with least amount of resistance..

Tue Aug 06, 2019 8:40 pm

ekacpuc wrote: It makes sense that if the condenser wire is contacting the distributor body that would make a route of less resistance instead of going the way it was suppose to.
Its actually not about which path has lower resistance, or not. If there is a short at the condenser, it means when the points OPEN there is no change in current flow thru the ignition coil. It is the same as the point contacts being permanently CLOSED.

The way the Kettering ignition works is that when the points are CLOSED a field charge is built in the primary winding. A comparable (but larger) charge is built in the secondary coil winding. When the points OPEN this primary field collapses when the current flow is suddenly cut and forces the secondary charge to seek a ground thru a spark plug. This secondary discharge is in the 10K-20Kv range.

Unfortunately, condenser failure is usually internal to the condenser and cannot be seen.

Tue Aug 06, 2019 8:48 pm

ashman40 wrote: ekacpuc wrote: It makes sense that if the condenser wire is contacting the distributor body that would make a route of less resistance instead of going the way it was suppose to.
Its actually not about which path has lower resistance, or not. If there is a short at the condenser, it means when the points OPEN there is no change in current flow thru the ignition coil. It is the same as the point contacts being permanently CLOSED.

The way the Kettering ignition works is that when the points are CLOSED a field charge is built in the primary winding. A comparable (but larger) charge is built in the secondary coil winding. When the points OPEN this primary field collapses when the current flow is suddenly cut and forces the secondary charge to seek a ground thru a spark plug. This secondary discharge is in the 10K-20Kv range.

Unfortunately, condenser failure is usually internal to the condenser and cannot be seen.

Right that makes sense, the points would be open.

Okay so back to what confuses me. I might find the answer (I have kids, reading quietly isn't easy) but the condenser is what's messing with me. If a condenser is bad would there still be a spark at the points while turning over the motor?

Wed Aug 07, 2019 5:34 am

ekacpuc wrote: Okay so back to what confuses me. I might find the answer (I have kids, reading quietly isn't easy) but the condenser is what's messing with me. If a condenser is bad would there still be a spark at the points while turning over the motor?
It depends on HOW the condenser has failed.

If it fails with a disconnect (imagine the condenser wire has an internal disconnect) then it is the same as NOT having a condenser. There might be a spark visible at the points since the condenser is now disabled. Again, I don't know that this is a legitimate measure of a working ignition system?
The second way it could fail is shorting to ground. This is the same as the condenser wire being directly connected to ground. This basically results in the points being permanently CLOSED electrically even though they are moving open/close. I would not expect any spark as the current flow would be thru the condenser and not the point contacts.

Testing with a MM or test lamp that the points+condenser are functioning is the only surefire way of knowing the condenser is not shorting. Also, it may not be condenser failure only. Others have reported bad quality points that internally short to ground. This can be seen by disconnecting the condenser from the distributor body. If the points wire is still constantly grounded it points to a short somewhere in the points rather than the condenser.

Wed Aug 07, 2019 5:38 am

Quote: condenser is bad would there still be a spark at the points while turning over the motor?

If the points spark you have a bad condenser. That's the purpose of the condenser, to 'absorb' the back feed voltage from the coil when the points open so there is no spark on the points. That spark is what pits points.

Wed Aug 07, 2019 12:08 pm

The points in the last car I've messed with had a good spark to it. So I figured it was normal because the car ran fine. Must have been a bad condenser.

The problem I had yesterday was fixed by removing the tach wire. It all worked fine before so it must have rubbed the insulation off somewhere.

Wed Aug 07, 2019 12:41 pm

If you have a complete functioning distributor just swap it out and try it. In doing that you eliminate the rotor, points, condenser, cap and the distributor itself. I carry one in the parts kits timed and ready to install.