84 Grand Wagoneer Revival

[devildog80]

We did pull the MSD off, and all back to OEM with new ICM and new coil.

We checked, and have, full voltage to and out of ICM, over to passenger fender. Just do not get circuit complete through coil, with voltage to + side.

Checked coil ground...have good ground.....

WHY WHY WHY......... :/

[rang-a-stang]

If you pull the pickup connector, there are 2 wires. If you connect a multimeter across those two wires and crank the motor over, you should see slight voltage spikes as the rotor turns past the pickup. Its only a tiny bit though so you have to set your multimeter to (I think) millivolts.

That stock dizzy is a Ford Duraspark. If you look up "Duraspark pickup test" there are a few other tests you can run, too. I replaced mine a while ago and it was pretty cheap (i want to say less than $20?).

[devildog80]

Thanks, and going to test it.

For that much, not a bad investment in prevention

Mongo228 has an ICM wiring harness coming too, as that would eliminate the factory nightmare of random splices we found, to make sure we are dead on with connections.

Fingers crossed.....

[devildog80]

Have some of the parts that came with the truck listed in classifieds.

[devildog80]

Well........

Mongo228 and I replaced OEM - PO wiring for ICM with Painless Harness.....still no spark.

Diving into the distributor pick up coil, as this is the last thing not changed, but does test good?

Constant ohm's at 692 across outside terminals at the plug, but investigating further.

[cu4whln]

Dang..

I hate electrical bugs.. sooo frustrating !

[devildog80]

Mongo228 said to me part ways into the rewire yesterday....."If this does not work, we are dragging it out into the desert, and light it on fire" :/

Tried to encourage him to NOT do that.

Guess it is what you get, with these old trucks

It WILL live again!

[devildog80]

Suspect the distributor might be our weak link now, after wiring and power feed has all been verified.

Just absolutely no spark through coil.

[78 WIDETRAC]

Originally Posted by devildog80

Suspect the distributor might be our weak link now, after wiring and power feed has all been verified.

Just absolutely no spark through coil.

I know you probably looked at this thoroughly, I only noticed the hard brittle cracked wires on my original distributor when I removed it. Cracked 1/2 way between the distributor body and plug, right where the wires rest on the manifold. I honestly would have never noticed them had I not removed the distributor.

[devildog80]

That is a possible fault point, so we replaced the OEM wiring with new ICM harness, and looking at distributor pickup sensor now.

At least I know there is new wiring on the male plug side, and hope we find our trouble with the pickup wiring, but not too hopeful.

The pickup tests ohms, off the connector blades within limits, so yes pulling the distributor is probably our next step.

Thanks for the idea

Need all we can get!

[devildog80]

Also thinking of doing distributor recurve, while on the bench trouble shooting.

[rang-a-stang]

You shouldn't need a whole new dizzy. The pickup is cheap and easy to replace. I think I bought an MSD one, and it was like $40... took maybe 15 minutes to install?

[devildog80]

Correct no new dizzy needed, recurve you can use a factory distributor, as it is primarily just changing one or both of the springs down in the bottom.

Brings your power curve in at lower rpm.

That is what I took from the youtube vids I watched, with this one being most informative.

https://www.youtube.com/watch?v=7jFlXBCtNCM

[sierrablue]

Probably a dumb question here, but how do the other components of the ignition system look? You said you've been through all of the 12V stuff--but what kind of shape are the cap, rotor, plug wires, and plugs in? Is it possible that the plugs got gapped too far? Obviously you're working on making the distrubutor basically brand new, but just other things to double check if it still won't fire.

[devildog80]

Everything pre distributor has been checked, and now replaced new, and still no spark to the coil.

Not even looking at plugs yet, until I can get spark to pop from coil to distributor.

Distributor/cap/wires are clean and in good shape, but pulling it to be sure gear is ok, then check pickup to make sure it is good.

At same time, will change one of the springs in the bottom for recurve, then when we get it to fire, will regap all the plugs from MSD setting, now back to new ICM settings.

Even at MSD gap settings on plugs, we should be able to have spark from coil, which is our issue.

Replaced battery, start switch under dash, ICM, new ICM harness, coil.

Verified and checked on my CJ5 the new coil, existing coil wire, spark checking tool, that these all worked. Put them back on Wagoneer and no spark.

That leads me to distributor being the only thing we can see, that would cause a no spark issue. Ohms checks ok on distributor pickup, but forgot to rotate it when meter connected.

Thanks for the thought, and still open to any/all info to try and get this issue resolved