Should I have voltage on coil with key in the ON position?

[joshm121]

Just started digging into my new Bronco a little bit and the wiring is a mess. I Removed a bunch of stuff that at one time powered a sound system yesterday and now she will turn over but will not crank (all other electrical works). Before she cranked first try every time. It has electronic ignition installed so wiring diagram isn't much use. I'm thinking somehow getting power to starter but not coil or plugs.

Anyway, shouldn't I have 12v on the coil with the key in the ON position? I currently do not.

Thanks,
Josh

 

[DirtDonk]

Depends on which ignitions system you have Josh. Most (especially stock ones) should show voltage at the positive side of the coil with the key ON. But some, like capacitive discharge types (such as MSD 6's for instance) won't show voltage there until the box shoots it in right before firing.

And let's get on the same page word-wise, since there are some unusual cues here. The way you worded it was pretty clear, so I'm pretty sure I know what you're talking about, but "cranking" is when the starter motor is spinning the engine and NOT the actual act of the engine firing and running. So you can have cranking and not starting.
It literally is a carryover term from the original cars with hand-cranks.

The "turn over" part is where the two sides really disagree. But it's been used to describe the actual firing, or starting of the engine running for so long now, it's hard to say which way is correct. Or if in fact using it to describe both actions is correct.
You used it the same way I always have. Where the act of "turning over" is just the same as "cranking" with the starter spinning, but not necessarily starting the engine.
But many, many people have used that phrase to indicate the actual starting, or firing of the engine into a running state, for so long that it's hard for me to say it's not correct. Just not how I've used it all my life.
Like the British say "tick over" for a successfully started engine, some here say turn over for that. Which is kind of surprising, since we've spent almost 250 years trying not to do the same things, or use the same definitions for English language terms as they do! ;D

But in my mind, turning over will always be first and foremost, the starter cranking the engine.
Sorry for the preaching. But I figured it was a good excuse to bring the subject up here again. And I wanted to make sure we were talking about the same thing anyway.

Back to your question though, what all else did you disconnect that was part of your stereo? Anything from the key switch? Anything from the starter relay/solenoid (another fun word for discussion!) or anything from the fuse block?

Good luck. And again, sorry for the long-winded rehash.

Paul

 

[joshm121]

Forgive me, I know I don't always use the right terms, but I think we're on the same page. When I turn the key I can hear the starter going as if it is trying to "crank", but it never "fires" as in the motor never has combustion.
This was really disheartening. The thing cranked like a dream before. I didn't see any markings on the ignition but I'll take a look tonight.
As far as I remember, the only thing I disconnected was a wire coming through the fire wall from the ignition(through two fuses) and into the harness, set of wires going to each of the door speakers, and a wire coming form the harness going to ground. First thing I did was bring the wiring harness back out and try to hook it back up like I remember, but its a no-go.
Don't see anything going to a starter solenoid (actually haven't even found a starter solenoid yet, was wondering if ti was somehow tied to the ignition), and a wire that was hanging from the fuse block, but not going anywhere.

 

[DirtDonk]

Forgive me...

Oh the heck with that! Forgive me for going on about some little thing (like I tend to do) instead of acknowledging that if anything was consistent, it's the inconsistencies and morph-ability of the English language. American version that is... %)

...When I turn the key I can hear the starter going as if it is trying to "crank", but it never "fires" as in the motor never has combustion.
This was really disheartening. The thing cranked like a dream before. I didn't see any markings on the ignition but I'll take a look tonight.

There are colors to go by too, if you can't find the "+" and "-" markings. Do you know if it's a factory wiring harness? If so, the positive side will be Red w/green stripe. The negative color will depend on the year. Black for early points type and some point-eliminator kits like from Pertronix, and other colors for factory electronic.

What year is your Bronco?

As far as I remember, the only thing I disconnected was a wire coming through the fire wall from the ignition(through two fuses) and into the harness, set of wires going to each of the door speakers, and a wire coming form the harness going to ground. First thing I did was bring the wiring harness back out and try to hook it back up like I remember, but its a no-go.

Sounds like you could have jiggled an old wire and it just came loose or failed at a joint or connector. Can you take a couple of pics of your engine compartment? One at the firewall where the wires go through, and one around the battery and fender area on the passenger side.

Don't see anything going to a starter solenoid (actually haven't even found a starter solenoid yet, was wondering if ti was somehow tied to the ignition), and a wire that was hanging from the fuse block, but not going anywhere.

Probably not the wire at the fuse box, but we can't overlook anything at this point.
The starter relay (most call it a solenoid, but Ford calls it the relay that it is) is the small black or gray cylinder thingy mounted to the inner fender near the batter. The main positive battery cable usually goes straight to the relay.
If your starter has been changed out for a later model with the integrated solenoid piggybacking it, then the PO might have eliminated the fender-mounted relay. Not usually a good idea on Broncos, but some still do it and it can work sometimes.

So, pics if you can please, just to get us going and whet our appetites for more under-hood shots.

Thanks

Paul

 

[69red]

on the starter relay, there should be two small wires. one hooked to a lug labled "S" and one labled "I". the "I" wire is brown (on mine at least). this wire powers the ignition system while the starter is spinning the motor. if it is unhooked your engine wont catch. check to see that this hasnt been knocked off by accident.

also if you have been runniing the starter alot, and it is sounding slow and laboured, put a charger on your battery and get it fully charged. if you run the battery dead, it damages them. no sense adding more to the to-do list

Good luck!

 

[DirtDonk]

Or the "to pay for" list either!

Paul

 

[joshm121]

I found it. One of the wires going to wiring harness was the power wire for the electronic ignition. I'm going to assume it was connected to the dangling wire I saw on the fuse block. I checked and it and it has 12v in ON and 0 in OFF. Hooked it up and seems to be working fine.
I looked again I still don't see a starter solenoid. I don't think it has one. The wiring is... completely jacked. Looks like almost everything has been changed. This is going to be fun

I'll attach pics

 

[DirtDonk]

I found it. One of the wires going to wiring harness was the power wire for the electronic ignition. I'm going to assume it was connected to the dangling wire I saw on the fuse block. I checked and it and it has 12v in ON and 0 in OFF. Hooked it up and seems to be working fine.

Good start. But one thing is off here still. There should not be any power to the ignition system when the key is in the OFF position. Could run a battery down eventually, or burn out an ignition module or coil even sooner.
Best to double check, and if you see voltage to the coil with the key off, better unplug it for the time being.

And thanks for the pics! Helps a bunch. Might even need some more for further checking.

I looked again I still don't see a starter solenoid. I don't think it has one.

Yep, you're right. Where your large black negative battery cable is bolted to the fender well is where it usually goes. Or near enough to there to be hard to hide.
Looks like the PO wired in a newer style (PMGR or permanent magnet gear reduction) starter like found on newer engines.
Great upgrade, but only if it doesn't cause trouble from wiring it incorrectly.

I see another potential problem though. That large battery cable should go to the engine block. It's proper to have a ground circuit connected to the body like that, but the largest load on a vehicle like this is the starter. So the largest cable should go to the engine block as close to the starter motor as possible. A smaller and more convenient one can go to the body.
Just something to think about.

The wiring is... completely jacked. Looks like almost everything has been changed.

Yes it does. Looks like you started out with a '69 or '70, then added lots of upgrades like power steering and power brakes. Some of the wiring looks to be '71 and later, but some of the other details look like '70 and older.

Maybe a couple more pics of different areas can help us help you. More wiring shots around the fenders and firewall behind the engine. And some of the top of the engine too. Just to see if all the other systems are still functioning. Like PCV and vacuum advance and other vacuum stuff hooked up correctly.

This is going to be fun

That it is. That it is... %)
Good luck. Hope the fun stays that way and doesn't lead to hair loss and heavy drinking. ;D
Glad you got it running again though. That's a nice milestone. Now to keep it running even after you fix things. That's going to be the trick. Should have plenty of help around here though. Yours looks just like a lot of other engine compartments I've seen hereabouts. Lots of Frankenbronco experts to come up with solutions to problems when the crop up.

Paul