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Wed Mar 25, 2020 4:48 pm

on my coil I have 4 spade terminals, two positive. two negative. I know the hot wire from my ignition switch goes to a positive and also one to the chock pull off.
on the negative side, correct me if I'm wrong, but the condenser wire goes to one spade and the distributor wire to the points goes to the other negative. is this correct. this is on a 1972 VW super beetle dual port engine.

Wed Mar 25, 2020 5:01 pm

Just one wire on neg. post of coil, goes to both condenser and points. It's usually green if you're using
Bosch parts.

Wed Mar 25, 2020 5:05 pm

James gournay wrote: on the negative side, correct me if I'm wrong, but the condenser wire goes to one spade and the distributor wire to the points goes to the other negative. is this correct. this is on a 1972 VW super beetle dual port engine.
The point connect to the condenser and then the green wires goes to the coil.

Wed Mar 25, 2020 6:24 pm

Thanks GLENN. I was just double checking myself because my condenser is connected to my coil bracket not my distributor.. so my condenser wire will go to the negative side of my coil and a negative lead from the coil will go to the distributor.

Fri Mar 27, 2020 10:54 am

New coil, new condenser, turned on the ignition and cranked to check fire from coil but all I have is an intermittent yellow spark. Checked my connection, all good and snug. Any recommendations on where to look in order to find my problem? Thanks

Fri Mar 27, 2020 12:53 pm

I just thought I would throw these out there in case you wanted to improve your ignition system:

https://www.thesamba.com/vw/forum/viewtopic.php?t=728471&highlight=

https://www.thesamba.com/vw/forum/viewtopic.php?t=732536

Fri Mar 27, 2020 1:22 pm

Ok, I’ve checked my coil. It’s new, and it’s good, I’ve checked my condenser, it’s good, new one and I checked my coil wire and it’s good but when I resemble everything, no fire out of the coil wire. ???

Fri Mar 27, 2020 11:53 pm

Take some measurements and report back what you find...
Voltage at the ignition coil #15 (+) with the ignition switch ON. You should see nearly the same as battery voltage. 0.5v less than the battery is probably acceptable for a 40yr old car, but much less than 12.0v and you may start to have trouble.

Voltage at the ignition coil WHILE you are cranking the engine. The voltage at the coil will normally drop some as the starter is pulling current, but if the voltage drops below 10.0v the coil may stop firing altogether while the engine is cranking.

Resistance thru the ignition coil primary windings. Disconnect all wires from the ignition coil and place an ohm meter on the #15 and #1 terminals. The stock resistance between these two terminals should read 3.0-4.0ohms. Much less than this and you will burn point contacts.

As a test,
Remove the wires from the #1 (-) terminal of the ignition coil.
Place a jumper wire on the #1 terminal long enough so you can ground the loose end of the jumper wire.
Turn the ignition switch ON so there is 12v at the #15 terminal of the coil.
Remove the HT wire from the center of the distributor cap and hold the exposed conductor at the end of the wire within 2mm of a ground.
Ground the jumper wire. Nothings should happen.
Remove the jumper wire from ground and you should see a spark jump from the end of the HT wire to the ground 2mm away.
Repeat a few times. This confirms the coil is functioning.

Next, remove the condenser from where it is grounded and wrap it in a rag so the body of the condenser cannot ground.
Rotate the crank until the points are closed.
Disconnect the jumper wire and reconnect the points wire to the #1 terminal of the ignition coil.
Turn the ignition switch ON.
With a plastic or wood stick, open the points while you hold the HT wire 2mm from ground. Each time you open the points the ignition coil should fire a spark.

Reconnect the condenser.
Repeat the test of opening the points and watching a spark fire from the HT wire to ground. Ideally, with the condenser connected you should get a larger/stringer spark.
If after connecting the condenser the HT wire stops sparking, it confirms the condenser is bad.

Test the condenser.
Remove the condenser from the car.
Test1: Set your multimeter to read resistance. Place one probe on the end of the condenser wire. Please the other probe on the body of the condenser. You may see the meter initially read a resistance, but after a few seconds the resistance should go to infinite/open. This is normal for a working condenser. If the meter ultimately shows zero resistance or any measured about of resistance It indicates the condenser has internally failed. A working condenser has not physically connectivity between the end of the wire and the body of the condenser.

Test2: If you MM has a capacitance setting, use this setting and test the condenser with the probes connected the same as above. After as much as 30sec connected to the condenser the meter should give you a reading of microfarads. This shows that the condenser is storing a charge like it should. If the reading remains at zero the condenser is bad.

Sat Mar 28, 2020 7:04 am

James, your response after Glenn's description still bothers me and is not clear.

The routing on your the negative side of the coil is from coil to condenser. The condenser will have two wires the other wire goes to the plug on the side of the distributor body where it passes through to the interior of the distributor where the points wire connects.

So your condenser was originally attached to the coil bracket? That may have fried the condenser, I'll have to dwell on that a bit.

The second negative terminal on the coil is not part of the stock ignition system

Sat Mar 28, 2020 7:52 am

Thanks guys for your replies, I appreciate them very much. I’ll give them a try today. I’ll let y’all know the results when finish. Thanks again.

Sat Mar 28, 2020 8:01 am

tasb wrote: I'll have to dwell on that a bit.

Just don't dwell to hard on one side.

Sat Mar 28, 2020 8:03 am

James gournay wrote: I was just double checking myself because
my condenser is connected to my coil bracket not my distributor..

Are you saying you have a condenser on the coil bracket?
As TASB said this is not normal.

Look at GLENN's picture of a distributor. The condenser should be inside the dist and have one green wire going to the coil minus terminal.

The car will actually run without the condenser, they are only put there to reduce the arc when the points open which extends their life. As an experiment you might try disconnecting the condenser that's on the coil bracket altogether and see if you get a better spark.

Otherwise ashman40 has provided you a useful fault tracing tree for step by step testing so go through this and report back.

Sat Mar 28, 2020 8:13 am

Occasionally you do find condensers beside the coil used for radio noise suppression, this might be confusing.

Sat Mar 28, 2020 8:18 am

Originally the coil may have Been inside the Distributor cap but many years ago a mechanic replaced the distributor because the old one had some slop in it causing the car to have a hesitation problem when first Accelerating. But when I installed the new coil and condenser, I relocated both the coil and the condenser to the fan shroud on separate mounting screws. At first I installed the coil in a horizontal position for appearance purposes but read somewhere that a coil should never be installed that way so I changed the position to about a 45 deg. Angle. Not sure how much truth there is in that but it was an easy try when desperate. Lol

Sat Mar 28, 2020 9:42 am

James gournay wrote: At first I installed the coil in a horizontal position for appearance purposes but read somewhere that a coil should never be installed that way ...l

Ever seen a Type 4 VW engine? The coils are mounted horizontally.

Sat Mar 28, 2020 9:44 am

kreemoweet wrote: James gournay wrote: At first I installed the coil in a horizontal position for appearance purposes but read somewhere that a coil should never be installed that way ...l

Ever seen a Type 4 VW engine? The coils are mounted horizontally.
Fine for the stock coil, bust some oil filled can exposed the internal windings.

Sat Mar 28, 2020 10:50 am

If it is not one thing it is another, my volt meter dash ohms meter has decided to discontinue working this morning. I placed a new one on order hopefully It will be in for the first of the month. I would like to go out and get another one, but right now I’m in 14 day quarantine. As soon as I have a new meter I will answer your questions. Thank you very much for sharing your knowledge, and y’all have a great weekend . Be safe.

Sat Mar 28, 2020 11:29 am

Change the battery on the VOM?

Sat Mar 28, 2020 12:54 pm

I did that but sill very inaccurate. Example 12 volt car battery registered 300 DC volts. If that were the case I’d have an electric VW. but, thanks for the suggestion, I’m sure little things like that happen when a person get frustrated. Lol

Sat Mar 28, 2020 1:08 pm

Electrically, the condenser can be placed anywhere between the coil #1 terminal and the points... as long as the body of the condenser is properly grounded. The coil itself does NOT ground thru its bracket.
The only problem I see with mounting the condenser to the fan shroud is it may not offer the best ground. Because the shroud is painted, the only path to ground is indirectly thru the sheet metal and screws that hold the shroud to the heads and the generator body. I can’t think of anything that is normally grounding thru the shroud. If possible, move the condenser back to the body of the distributor which is solidly grounded through the engine case.

Test your condenser as suggested above. When condensers fails they can short internally which permanently grounds the #1 terminal. This defeats the points which are opening and closing a path to ground. The coil never sees the ground open so never fires a spark.

If your ignition coil is oil filled (shake it and listen) then the manufacturer probably has a recommended orientation. As Glenn pointed out, if you install them incorrectly they can overheat. Read the install instructions and follow.
If it is epoxy filled then it doesn’t matter how it is oriented.
For both, leave enough room around the coil to allow heat to radiate.