440IC can't get spark

[jdemaris]

I am defying science I guess and I am doing all the steps. Trust me.

So do I buy another cap then?

No, you're not defying science - just mssing something along the way.

I'm not trying to sound arrogant, or like a know-it-all - but . . . it's a pretty simple system without too many variables. Like anything though, something is only simple when you fully understand it, and/or have experience with it. There are many things in other areas that are complex to me, and simple to other oeople. That's just the way it goes.

In your case, you've got spark when you eliminate the cap and rotor - but how much spark? Keep in mind it takes a cetain amount of high voltage to travel through that rotor to the cap, and takes less whey it's bypassed. So, you need to determine is your spark is low to start with, or is correct and you have a cap and rotor problem.

Just take a spark plug and either break off the ground electrode, or bend it way out of the way. This way the plug has to jump a near 1/4" gap. If all is working as it should, your coil can jump this extended gap. If not, the spark is too weak and your problem is somewhere else - and not caused by the cap and rotor. Checking for spark with a properly gapped spark plug out in free air is never a good test.

[Tim_in_IA]

jdemaris,

I was checking all the locations you mentioned before. I was getting power. but no spark at all. Which lead to the weak ground assumption. I installed new wires and that got the coil to spark while hooked to the condenser and points, so I can rule out those being bad. I have checked everything you said. Many, many times. It is just process of elimination. The spark I am getting direct from coil now is 1/4" long. So I know the park is strong. Good color. The only thing that would make the spark go away was snapping the cap on.

I read an article today that mentioned water could get in the cap somehow and short it to the body. This must be what is happening now even though the cap is only a year old. I'm picking up a new cap this week hopefully and we'll find out soon enough.

I really appreciate everyone's posts. Especially the one that talked about coil theory and what is happening. It is really simple when you think about it but that made it easy for me to test for a good or bad coil. Thanks again everyone. Will keep you posted.

[joeturner1977]

Is it possible that you might have a bad coil wire??? Maybe works when you bend just right... Sounds like you almost got it figured out.

Good luck

[Tim_in_IA]

yeah it is possible that one of the coil wires was bad. I just put new ones on. And the spark plug wires were new with the cap.

I know there was a bad wiring issue. so all the old wiring is out. Now I've got it locked down to the dist cap as a point of failure. It looks new looking at it. Everything still shiny. I honestly don't know how it would ground out or what to but it kills the spark. So my wife is going to the farm store today and if they have caps she'll get one. Otherwise I'll order another from Lavoy.

[Gil]

To see if moisture is your problem, remove the distributor cap and the plate the points sit on. Below that is the centrifugal advance mechanism. Make sure that it is working by twisting the distributor stem with your fingers. The arms and the springs should move easily. If there is moisture in this area sop it up with a paper towel and blow it out or let it air dry. This is a common problem with crawlers that sit out in the rain or are parked in humid conditions for a long time.

[Tim_in_IA]

To see if moisture is your problem, remove the distributor cap and the plate the points sit on. Below that is the centrifugal advance mechanism. Make sure that it is working by twisting the distributor stem with your fingers. The arms and the springs should move easily. If there is moisture in this area sop it up with a paper towel and blow it out or let it air dry. This is a common problem with crawlers that sit out in the rain or are parked in humid conditions for a long time.

This is interesting. How would water in this area modify the current? When the points are connected it is still sparking but the cap makes the difference. I guess I just assumed all the lower internals of the distributor were grounded?

[Gil]

It is like throwing your toaster in the bathtub.
The moisture conducts the current to ground.

[jdemaris]

jdemaris,

The spark I am getting direct from coil now is 1/4" long. So I know the park is strong. Good color. The only thing that would make the spark go away was snapping the cap on.

If you have good blue 1/4" spark, but it's not making it's way through the cap and rotor route - first you've got to find out if your points and cap/rotor are in proper sync. If your spark occurs at at time when the rotor is inbetween cylinder poles - it won't work. I've seen that happen many times. Even on my little 1010 with a Delco distributor.

Either your points are out of time with the rotor position, or the carbon-pole in center of the cap is bad.

With your cap off, getting spark directly from the coil, stop the engine just as spark occurs. Then stick the rotor on and see where it's pointing. It is supposed to be right in line with a one of the cylinder conductors in the cap. If not, you've got to change your point gap or rotate your breaker plate to time it properly. If spark occurs when that rotor is inbetween the coil volage will rise as high as it can, and then give up if it can't reach its way to ground somewhere.

[Tim_in_IA]

I ordered a new cap from Lavoy last night. They didn't have anything in the local farm stores. Will try this next and if that doesn't work I'll take the plate out and spray some air in there to dry out any moisture.

[jdemaris]

I ordered a new cap from Lavoy last night. They didn't have anything in the local farm stores. Will try this next and if that doesn't work I'll take the plate out and spray some air in there to dry out any moisture.

Did you check the rotor timing?

[Tim_in_IA]

Did you check the rotor timing?

Not yet. It wasn't that it wasn't making it out of the cap. It was that the action of just putting the cap on made the spark go away. So for some reason putting the cap on is shorting out the points. The coil wire again going right to the frame. Not even through the rotor and contacts. So I need to resolve the issue with the cap before I go further. Does this make sense how I am describing it?

[jdemaris]

Did you check the rotor timing?

Not yet. It wasn't that it wasn't making it out of the cap. It was that the action of just putting the cap on made the spark go away. So for some reason putting the cap on is shorting out the points. The coil wire again going right to the frame. Not even through the rotor and contacts. So I need to resolve the issue with the cap before I go further. Does this make sense how I am describing it?

No, it doesn't make sense to me. Not sure if the problem is your description, or my comprehension.

Either the points/condensor/coil are producing ample spark, or they are not. If they are ?

Then, it's not making it though the distribution network - which involves the cap, rotor and wires.

You say the you've got good spark before the cap, correct? You're checking with a lead coming directly from the out secondary high-tension output - i.e. the coil wire.

You then put the cap on - and lose the spark? How are you now checking? Are you saying you are clamping the cap on, but still checking spark directly from the coil output? And then, spark stops? If so, you obviously have some sort of mechanical interfernce pushing on something - either somehow interfering with points operation, or pushing on an insulator, connection, etc. If you have the correct parts, the cap touches nothing but the OD rim of the distributor housing - so right there you've got an issue that ought to be overt and obvious. Can you take a photo and post?

[Tim_in_IA]

You say the you've got good spark before the cap, correct? You're checking with a lead coming directly from the out secondary high-tension output - i.e. the coil wire. (yes this is correct)

You then put the cap on - and lose the spark? How are you now checking? Are you saying you are clamping the cap on, but still checking spark directly from the coil output? And then, spark stops?
(yes this is what is happening)

If so, you obviously have some sort of mechanical interfernce pushing on something - either somehow interfering with points operation, or pushing on an insulator, connection, etc.

(There is a condenser wire in there that could be cought, I never thought of something blocking the points .... wait, this isn't it. When I have spark I have the dust cap on and the rotor. So the only thing that could interfere would be the rotor and the dust cap. I have another new rotor I can try to put on. All the parts I got from Lavoy so I am fairly certain they are the correct ones. I couldn't believe it when I would take the cap on and off and it would spark or not spark even with the circuit not going through the cap. Does the cap have internal pathways that could be shorted? even so it isn't even part of the secondary coil circuit at this point. It is baffling. I'll take pictures next time I work on it. I'll see if I can test it again tonight. Thank you!)

[jdemaris]

When I have spark I have the dust cap on and the rotor. So the only thing that could interfere would be the rotor and the dust cap. I have another new rotor I can try to put on. All the parts I got from Lavoy so I am fairly certain they are the correct ones. I couldn't believe it when I would take the cap on and off and it would spark or not spark even with the circuit not going through the cap. Does the cap have internal pathways that could be shorted? even so it isn't even part of the secondary coil circuit at this point. It is baffling. I'll take pictures next time I work on it. I'll see if I can test it again tonight. Thank you!)

I still don't understand what you are checking, and how. When you put that cap on, and you lose spark, exactly what spot are you checking from? The cap or the coil?

When all is hooked up, the current-making spark leave the coil secondary (high tension tow) - and is delivered to the distributor cap. Then runs though the center-mounted electrode and contacts the rotor via a carbon-pole (in most cases). Then runs out to the tip of the rotor. From there, as long as the spark is timed properly, spark occurs just as the rotor is pointing to one of the poles in the cap and jumps a small gap - and then makes it way to a spark plug.

There is something lacking in the description, so I'm not sure what you are actually doing. I will note that some brands of distributor caps have a spring-loaded center carbon electrode - and sometimes it fall out and gets lost - which would result in no spark. Also, as I said before, if spark occurs when the rotor is inbetween cylinders, or even installed 180 degress out of wack, you'll get no spark. All should be very easy to see.

[Tim_in_IA]

both tests are direct from coil, no cap in the circuit.

The only bearing the cap has on this is that it makes the spark go away. it isn't even part of the circuit yet. All it could do is cause something to short with the points. I don't understand why. I've looked at the distributor diagram many times and I still don't see a connection. A previous poster said it was like throwing a toaster in a bathtub. I don't see where the current goes down into the bowels of the dist at all, except for when the points ground and complete their circuit. Why would it matter? I don't know.

All I can tell you are my observations. I start the test. All the contacts of the coil show -6. I can short out the points and it goes to 0 on the + terminal (and creates spark if I have the coil wire near frame), I put the dust cap and rotor on. I test from coil to frame and spark when I turn over the engine. I put the cap on, still testing from coil direct to frame (not wired through cap) and no spark. It doesn't even make sense to me.

I can offer one thing. When I was putting everything together I put dielectric grease on the contacts. I was told after that not to do this that all the connections inside should be dry. I have since then put new points in so they are dry. The current dist cap I have has the grease on it but I cant get it all off of the carbon. I probably ruined the cap. I don't know what difference it makes. That grease is supposed to improve the connection. Now it could be that when I put the cap on it forces the rotor down onto something grounding it out, but before putting the rotor on the dust cap sits flat. Nothing obvious here.

I'll try to take some pictures tonight. Ok I'm not done keep reading...


After writing that whole mess above I found myself looking at the end of my second paragraph. With the cap off less pressure is on the dust cap and rotor. I wonder if there is something on the underneath of the dust cap that when clamped down tight keeps the points from closing. It is a long stretch but it makes more sense than anything so far. It would work without the cap on since the dust cap could move a bit and allow the points to open and close, but if clamped down with the dist cap over it it s too snug and allows some kindof imperfection or piece of plastic to keep the points open. I could try for spark with the distributor cap loose.... ???