Yeah, just the area around the coil and distributor in front of my carb burnt. Luckily I got it put out before it got through the fuel line next to it. Was a good chance to upgrade to HEI though.

 

Sounds like your ignition switch could be acting up. It happens all the time with old things.
Reason I say check that is that if your alternator is not charging, it could be from the Green w/red wire not turning on the regulator.
If the ignition is only sparking when the starter is cranking, the Red w/green wire to the ignition coil might not be getting powered from the key. Only during crank it's getting powered up from the Brown "I" wire on the starter relay.

A few other comments on what you've already tracked down:

Many alternators and regulators are lucky to last 10 months these days! Much less ten years. Nowadays you can't even rule out brand new parts as being good until you've verified. Many a hair has been pulled out because someone figured the new parts must be good because, well, they're new!
Besides, neither an alternator or a regulator can keep a truck from starting. Yes, they can let the battery go dead of course, but it sounds like that's not the issue here.

Also no guarantee it's good. Three years is plenty of time for a battery to die. Especially when it sits for extended periods or has been killed and brought back from the dead a few times.
The more that happens, the more likely the battery is to die permanently.

This is after charging the battery for awhile? Or does your charger have a high-amp "start" mode you're using?
If you can crank the starter with the charger when the battery is otherwise dead, then the starter and it's cables sound to be good.

Replaced with what type of tank? Stock replacement or fabricated aftermarket. Is this for the electric fuel pump, or are you running an inline pump?
If aftermarket, there could have been a CRAP-TON (official measurement of fuel tanks by the way!) of metal shop debris in there. A fuel filter will get clogged quickly with this type of tank unless you clean it out manually first.
Not guaranteed of course, but at least a possibility.

As said, obviously the alternator was not working at that time.

This is where you need to check for fuel coming out of the injectors (carefully!) to see if that fuel smell is fuel being delivered and no spark, or if there's no fuel being sprayed into the throttle body.
Is this a TBI unit? Or is this some Ford factory swap stuff? If factory you can't just look at the injectors of course, but with a TBI you should be able to see the spray without sticking your face right above the opening, while waiting for a backfire to singe your hair and eyebrows off!

Again, sounds like the starter, relay, cabling and at least part of the ignition switch are all ok.
And yes, the switch can be bad but still power the starter relay/solenoid. Your ignition, regulator, starter and accessories are all on separate circuits from the switch.
In some cases though, the ignition and regulator are literally on the same contact at the switch. If this failed then, it would explain why your alternator and ignition suddenly went dead but your key will still activate the starter.
Sounds like some switch tests are in order.

Easy enough to do with the voltmeter though. With the key in RUN verify the voltage at the Red w/green wire that's probably connected to the MSD box. Not sure if that's the right wire to use there (because it's a resistor wire) but at least find it to see where it goes under the hood.

Then check the Green w/red wire at the voltage regulator's 3-wire plug. Or maybe it's a 4-wire plug in your case? I don't remember if you said your truck has full gauges with an ammeter, or just a few gauges with a charge indicator lamp. Either way that wire needs 12v at the regulator only with the key in RUN.

Generally speaking, if a battery can spin a starter motor, it's got more than enough capacity to spark the ignition. But if it's right at the verge, it might not be enough to do both.
However, you said it was spinning the starter pretty good? Should be fine for sparkage as well then.

There are tests, but I don't remember which wire to do what to at the moment. Probably an instruction and trouble-shooting sheet on their website though.

Check those Green and Red wires first though.

Good luck

Paul

 

Ok, I’m having trouble. I’ve tested MSD according to their website. It sparked. Next tried to test pickup in dist. Not really familiar with ohms. Over my pay grade. I have a Fluke multimeter. I think set to ohms. Got on truck 2.5? Tested another I have, don’t know if it’s good, got .5? I also have a third nib I’ll test tomorrow. I was told they should be 400-700?

Another totally different possibility is MSD box is getting intermittent power from ign switch. Which I could put multimeter on wire and turn key on and off repeatedly???

Oh yea and replaced fuel tank with factory replacement 19 gallon rear plastic one. And a master battery cutoff is in the works.

 

To measure Ohms (resistance) set the dial indicator to the "upside down horeshoe" looking thingie on the meter. Is your meter auto-ranging? If not, set it to 2K in the ohms section. Here you'll read anything from 1.0 to 1999 ohms.....if it's auto-ranging it'll read the exact resistance.

I don't know what 2.5 or 0.5 is because no setting was specified...if you were on ohms.

And, yes....if the stator is good, a reading of 400 - 700 ohms is what you're looking for.

As stated before by 1 Ton, the Gr/r wire(s) on the ignition switch are the bad boys with ignition.

The "I" terminal on the starter solenoid should have 12VDC when CRANKING only.

Re-read post #13 if need be.

 

To add to what Filthy Beast said about the "I" terminal, in a properly connected system you will actually see voltage at the WIRE because it's connected to the Green w/red wire up near the back of the engine usually.
If you remove the wire from the I post on the starter relay/solenoid and read only the stud itself, then you will see 12v only when the key is in START.

Confused the heck out of me the first time I measured with the wire connected. Took me a minute to realize what I was seeing.

I wonder if your meter was telling you 250 ohms on the first reading and 500 on the second, but in the wrong scale? If so that would indicate that the first one was out of range and needs replacing, and the second one was right on the money. It certainly tells you at least that the two were showing quite a bit of a different value. Which is something of note.

Paul

 

Still nothing. No spark now
Tested pickup in coil with cousins meter. 440 ohms so good I guess
Had alt tested. Good
New voltage regulator
New ignition switch
Tested MSD, per website good
Good wires to ground
Coil, have spare, but how do you test?

 

Did you test the ignition switch or the wires for power yet? That's what we were discussing the other day. I see you replaced the switch itself, but what about the wires to it?

Could still be the ignition switch if power is not getting to the right points.

Close to the minimum, but if the ohm-meter is accurate then it's good.
But you might verify that with a known-good meter if one is available to you. $5.00 or free at Harbor Freight if you have one nearby. Or the best $20-30 bucks you can spend elsewhere when owning an old truck.

That's good to know, but it has nothing to do with spark. So you still have to test other things.

Keep the old one handy. New does not mean good anymore, so you may end up chasing your tail down the road thinking that you have another issue because your new regulator has to be good. Well, it doesn't.

Well, now we're on to something. Again, "new" does not mean good, but luckily most new ignition switches work at least passably well even if they don't always last as long as the originals.
So now you still have to test it, and look more closely at the associated wiring because the switch could be good.
This is where a volt-meter or test light will come in handy. You need to verify you're getting power to all the right places.

Good.

Which ones where? You do have one directly from the battery to the body/fender area?

Pretty easy too. But unless you know what the coil is from (is it an original Ford by any chance?) you may not know the correct ohms reading to look for.
Just like the distributor bits, the coils have a range of resistance between two of the electrical contacts, but I don't remember what they are off-hand. Someone here will, or you can find it in the beginning of most shop manuals under the testing and trouble-shooting procedures.

Or you can do it the old fashioned way. Temporarily connect a 12v line to the positive side. Put a spark plug or coil wire in the tower and lay it near a grounded point on the engine or body (but NOT near the ignition modules!). Then with a temporary jumper wire, connect the negative side of the coil to ground.
Every time you touch and remove the wire from the negative side of the coil you should see/hear a big fat strong spark. This is just like making and breaking the contacts between points or electronic triggers. Same thing only manually.

If you do not see a spark, or the spark is a weak orange and won't jump very far, the coil is not worth using. If on the other hand you get a big loud white/blue spark that can jump the grand canyon and makes you very afraid to get your hands anywhere near the business end of the coil, that particular coils is good to go.

Paul

 

Finally found it!
Thanks guys for the info.
The truck got so it would only crank sometimes. Played with ign switch. One of the clips holding the plug into the back of the ign switch was broken by po. When I would hold switch together forcibly, truck would crank and even fire, but shut off when switch released. So I cut ign wire to MSD, and put a temporary jumper to the battery, squeezed ign and it fired right up. Didn’t have time to make a more permanent fix, but at least I know what it is. Should/can I replace connector on back of ign switch or should I just squeeze it and put a zip tie on it?
And to compound things, fuel pressure gauge on throttle body quit working, so thought fuel pump had died. But it reads zero when engine is running, so must not work.

 

Great news! That's the kind of thing you have to always look for when diagnosing something. Long before you start throwing parts at it. These trucks are gettin' a little long in the tooth these days. Lots of little stuff like that going to throw you some curve *****.

And yes and yes. You can zip-tie it, but it's just going to come back at the most inopportune moment. So I would get a new connector if they are available. If not I would figure out a way to make it work more solidly and reliable somehow.
But hopefully the new stuff is available. It is for the old Broncos so it should be for these trucks too.

Paul

 

Glad you found it.......sometimes the simplest/most obvious is the answer.

 

Good work mate, glad to hear you got it. Sometimes these question threads just die and you never know if its another truck that gets abandoned out of frustration... good work for making her live!

I'd definitely sort out the plug retaining clip, and a ziptie might just work so long as it doesn't move around. YOu can always cut it later if you decide to put on a new plug.

- boingk

 

I’ll probably zip tie it for now, while I look for a plug. A buddy of mine has a couple parts trucks.
On a separate note, if I’m checking ign, can I just unplug “s” terminal on the starter relay to disable starter, or does it serve other functions?

 

The S post has only one function, and that's to let the key energize the starter.
But What is it you're trying to do? If you really want to disable the starter from any chance of spinning while you work around things, you must either disconnect the battery, OR, if you need power to other things, disconnect the main starter cable from the starter relay.

Doing this means that some mistake up top with wires won't get the starter motor all excited.
But if all you're trying to do is keep it from starting while yo mess about with the ignition switch, then yes, disconnecting the Red w/blue wire from the "S" post will do that.

Paul

 

While you're at it, might as well disconnect the Brown wire from the "I" post as well.
Since it has power with the key on, you will still have things powered if the key is in the run position or you are fiddling about with the wires.
In a perfect world that Brown wire can NEVER energize the relay, but I don't know if it's physically impossible, so disconnecting it seems prudent.

Paul