I have a 1980 Ford E150 van with the 302 motor and an adjustable MSD timing control. The shop said I had a bad stator in the distributor. I replaced the distributor with a remanufactured unit from Napa. The van started pinging excessively (even with the timing control turned down) and the mechanic could not figure out why. I contacted Napa and was given a replacement. That was installed and the van was running so poorly that it seemed it was missing on two cylinders. We reinstalled the original Napa part just to make it driveable until I could figure this out. The van had only a very minor pinging problem prior to the Napa part. Easily cured with 91 octane fuel. For my own education, what would cause this issue? Would a MSD Pro-Billet distributor help? Thanks.

 

Where did the original dist come from that failed? And who put the msd unit on? Is the engine completely stock, or has it been modified(emissons removed, new carb?).

It sounds like the dist that was in there originally had a different timing curve or a different vacuum advance unit. Or it has been modified for a less aggressive timing curve.

If you had the money, an aftermarket dist would probably help because they are more easily adjusted as far as timing curves and such.

One important question that I should have started with. Do you have an idea what the timing was set at before the old dist failed. Someone may have had it turned back a little, especially if the EGR valve has been disconnected. If that was the case, and you are trying to set the timing according to the book, it will probably ping if the engine is not stock.

 

Thanks for the reply. Stock engine. The distributor that failed was a remanufactured unit from Napa as well. I was able to get 5 years out that unit. All smog equipment is functional and unmodified. I installed the timing control myself after a couple of batches of bad gas. The timing has always been set to 12 BTC with the vacuum hose plugged and then reinstalled after timing is set. Could there be that much difference in quality from one Napa distributor to another??? Options? Thanks again.
Jory

 

I forgot to mention that the car will ping the same whether the vacuum hose is hooked up or not. Thanks again.
Jory

 

Well you would think the dist's were all the same from them, but apparently not. You said it still pings with the vacuum line off the dist, so I guess it's not vacuum advance unit either.

I would make sure your egr is working correctly, and not clogged up. While it's idling, you should be able to push up on the diaphram on the egr and make the engine stall. If it doesn't run rough and try to stall, the the passages are clogged and will have to be cleaned out.

If you can see the egr(kind of hard sometimes), with the engine totally warmed up, rev the engine, and you should see the diaphram/pin in the egr slowly rise, and you should start to feel vacuum on the egr line if you hold your finger over the end of the line. The egr is very important to keep the engine from pinging.

If the egr is working, the only thing I can recommend is turning the timing back a little to see what happens.

Also make sure the engine is not overheating. This will cause it to ping too.

 

Thanks Dave,
The EGR is functioning properly. Since it does not seem to be the vacuum advance could it be the springs inside? Are they replaceable?

 

I have the feeling that they don't check the advance curve on the "re-built" distributors. You could check the curve by extending the timing marks on the dampner. See what you get at different rpm. I have come across vacuum advance units that were giving way too much advance. You could check that with a Mity-vac. The springs can be changed. Crane has a kit with springs and a adjustable vacuum advance.

 

Stators are in electrical motors, generators, and alternators, not in car distributors. The term specifically refers to that part of the electromotive apparatus that is "stationary."

Armatures are in electrical motors, generators, and alternators, not in car distributors. This term refers to the part of the electromotive apparatus that rotates on a device called, aboriginally when electricians were physicists specializing in Maxwell's field of electrophysics, armatures because they resembled a human arm's ability to rotate things.

Sometimes they both have electrical windings used in both the generation of electricity and the electromotive use of that generated electricity; a generator is a motor wired in the other direction.

None of these is a 'distributor.' A 'distributor' distributes electrical sparks in pulses for the purposes of internal combustion engine ignition. There is no stator in a 'distributor.'

"Stator" does not even imply anything to do with a static charge of electricity either!

Conclusion: go to an educated shop and stop believing statements from mechanics that are nonsense and make no sense.

 

Napa part #ECHMP700 is an "Echlin Ignition Distributor Stator (Pick-Up)". This from the Echlin training program: "
Looking at the Ford section of your ignition catalog (figure 6), you can see that Ford calls the rotating part of the trigger an armature and the pick-up component mounted on the distributor plate a stator". Hope this helps.

 

You are correct about the stator and armature terms being in reference to motors and ac/dc generators. And that's also what is contained inside the distributor of a Ford vehicle. The stator/armature assembly generates a voltage signal to trigger the electronic module. And I also lifted the description below from a common explanation of how the system works, and have highlighted where they use stator and armature in the text. This what the parts of the distributor are commonly known as.



"BASIC OPERATING PRINCIPLES

The Ford Solid State Ignition is a pulse triggered, transistor controlled breakerless ignition system. With the ignition switch ON, the primary circuit is on and the ignition coil is energized. When the armature spokes approach the magnetic pick-up coil assembly, they induce a voltage which tells the amplifier to turn the coil primary current off. A timing circuit in the amplifier module will turn the current on again after the coil field has collapsed. When the current is on, it flows from the battery through the ignition switch, the primary windings of the ignition coil, and through the amplifier module circuits to ground. When the current is off, the magnetic field built up in the ignition coil is allowed to collapse, inducing a high voltage into the second windings of the coil. High voltage is produced each time the field is thus built up and collapsed.

Although the systems are basically the same, Ford refers to their solid state ignition in several different ways. 1976 systems are referred to simply as Breakerless systems. In 1977, Ford named their ignition system Dura Spark I and Dura Spark II. In 1982 Ford dropped the Dura Spark I and introduced the Dura Spark III. This system is based on Electronic Engine Control (EEC). The EEC system controls spark advance in response to various engine sensors. This includes a crankshaft position sensor which replaces the stator and armature assembly in the distributor. Dura Spark II is the version used in all states except California. Dura Spark I and III are the systems used in California V8's only. Basically, the only difference between the two is that the coil charging currents are higher in the California vehicles. This is necessary to fire the leaner fuel/air mixtures required by California's stricter emission laws. The difference in coils alters some of the test values.

Ford has used several different types of wiring harness on their solid state ignition systems, due to internal circuitry changes in the electronic module. Wire continuity and color have not been changed, but the arrangement of the terminals in the connectors is different for each year. Schematics of the different years are included here, but keep in mind that the wiring in all diagrams has been simplified and as a result, the routing of your wiring may not match the wiring in the diagram. However, the wire colors and terminal connections are the same.

Wire color coding is critical to servicing the Ford Solid State Ignition. Battery current reaches the electronic module through either the white or red wire, depending on whether the engine is cranking or running. When the engine is cranking, battery current is flowing through the white wire. When the engine is running, battery current flows through the red wire. All distributor signals flow through the orange and purple wires. The green wire carries primary current from the coil to the module. The black wire is a ground between the distributor and the module. In 1976, the blue wire was dropped when the zener diode was added to the module. The orange and purple wires which run from the stator to the module must always be connected to the same color wire at the module. If these connections are crossed, polarity will be reversed and the system will be thrown out of phase. Some replacement wiring harnesses were sold with the wiring crossed, which complicates the problem considerably. As previously noted, the black wire is the ground wire. The screw which grounds the black wire, also, of course, grounds the engine primary circuit. If this screw is loose, dirty, or corroded, a seemingly incomprehensible ignition problem will develop. Several other cautions should be noted here. Keep in mind that on vehicles equipped with catalytic converters, any test that requires removal of a spark plug wire while the engine is running should be kept to a thirty second maximum. Any longer than this may damage the converter. In the event you are testing spark plug wires, do not pierce them. Test the wires at their terminals only.