LOS ANGELES: Painless Wiring Harness Help on '73 Bronco

[paddycurr]

Welp, today was the big day. Excitement was mounting, I'd done a bunch of grounding, wrapped all my wires, tried to make things tiday. I connected my battery, climbed in the cab, closed my eyes and said a prayer, turned the key and NOTHING. Nothing at all. No clicking, no fire, no explosion.

Nothing.

I'm gonna try calling Painless on Monday to troubleshoot, not a lot of internet help with testing the system, but thought you'd all like to know the big moment ended in a giant thud. UGH. Still, I'm hoping it's something small and simple and wanted to thank you all for your guidance in this very troubling time! ; )

 

[DirtDonk]

Well that sounds pretty underwhelming. But not the end of the world!
Yet…

Do you have a fuse in the fuse holder?
Is the fuse still good?
Do you have the main power wire (is it red, or Black?) connected to the battery side of the starter relay?

Does anything in the cab work? Heater? Radio? Headlights? Etc?

 

[fluffybunny]

It's got to be something simple. Something should work. Did you install the maxi-fuse (that mounts near the solenoid)?

 

[paddycurr]

Hi guys, thanks for popping in again.

The only set-up to the new harness that's different from the old is that I'm running a Pertronix Igniter III and replaced the factory coil with a Flamethrower III. I pulled out the points system and I'm now starting to not trust myself on that decision.

The maxi-fuse is installed beside the solenoid as instructed by Painless. I followed their wiring roll-out word for word. I'm not sure about the fuse holder, or the fuse itself, but I've taken pictures (see below). Nothing works, no clicks, no nothing. When I turn the key it's almost like the battery isn't connected at all. I have the negative side of the battery connected to the engine, as it was before, with a grounding wire on the negative side connected to a brass plate installed on the firewall (see photo). I have a grounding braid running from the body of the car to a mounting bolt on the starter. I believe the wires to the solenoid and the maxi-fuse are all running to their proper places, but there is absolutely NOTHING happening when I turn the key. No radio, no headlights, no power to the car.

I didn't do anything with the new fuse box in the glove compartment. Should I have flipped a switch or something?

Patrick

 

[DirtDonk]

First thing to do would be to measure voltage on both sides of that red fuse holder.
I see they have finally changed from the maxi fuse to what I believe is a midi fuse? At least it’s a slightly different holder than it used to be and Eric said they were leaning in that direction.

Measure voltage at the battery, then at the end of the short black wire that you installed onto one end of the fuse holder, then on the other end of the fuse holder.
Can you get a better picture so we can see what the fuse looks like? From here it doesn’t even look like there is a fuse installed.

 

[paddycurr]

I've got a multimeter in the mail, due here tomorrow. Assume that'll do the job measuring voltage from these different components.

A friendly reminder: outside of being able to follow directions and navigate pictures and diagrams in the Painless book, I'm absolutely useless when it comes to being able to identify what/where the fuse is. I know the fuse BOX is in the glove compartment! ; )

Here is a photo of what I think you're asking about:

 

[DirtDonk]

As the Mythbusters were fond of saying… “Well there’s your problem… “

I don’t see a fuse in the fuse holder.
Yes that is what I was talking about, and appears to be something along the lines of a midi fuse holder.
At the moment it’s simply a place to put the two wires, but with no connection in between. If you were to install a fuse, or even just a jumper wire between those two posts, you would likely have electricity everywhere that you need it.

Is there a fuse laying around unused in your box of parts from Painless? It would not be a normal plastic blade fuse like you would put in your fuse panel in the glove box. It would be along the lines of a rectangular black bit of plastic with metal ends with holes or slots sticking out of each side.
Usually with a marking on it such as 60A, or 70A, or similar.

 

[paddycurr]

Hmmmmmm... I don't see much that matches that description, though maybe it's these things? Also, what's your Venmo? I think I owe you a steak dinner ; )

 

[paddycurr]

Looks like maybe you mean one of these. I don't see this anywhere in my kit. I'm assuming without this there's no direct line from the battery to the igntion switch and might be the reason why absolutely nothing is happening?

 

[paddycurr]

MAYBE it could be these, although I can't imagine why there'd be 4?

 

[paddycurr]

OK, UPDATE: I did some solo, adult internet sleuthing and those last pieces were EXACTLY what I needed. I hooked them up to the midi fuse, cranked the key and the electrical came to life. It was such a thrill. My wipers worked for the first time. Newly installed LED headlights came on. My RADIO that I installed myself gave me some static. It's probably sounds foolish but this stuff is all waaaaayyyyy outside my realm, and it was such a great feeling when the key turned over the electrical came on. That said...

The starter revved and revved and revved. Before rewiring, getting the engine to turnover and kick on was always a bit of a challenge if I hadn't driven the car in more than a day. I'd feed it some gas and she's roar to life. This time... no roar. So now it seems like the electrical is all in working order but I've somehow now gotten in the way between the iginition switch firing the engine. Any suggestions?

 

[DirtDonk]

Great news! And yes, those are the things I was talking about. Looks like they give you one of each type and a spare of each type.
They give you multiples I’m guessing depending upon your load. At this point I would probably use the 70 amp versions since you’re just feeding the accessories in around the vehicle.
If there is a duplicate of that fuse holder for use between the alternator and starter relay, you would use the 150 amp version for a higher output alternator.
If you are just using a standard alternator and the normal wire in the harness (in other words not the upgraded alternator harness) then you would do whatever they say in the instructions.

I would have to reread the updated instructions. Probably no fuse, but if there is also a fuse with the same type of holder then you could use the second 70 amp fuse there.

As to why it won’t start when you’re cranking we don’t know yet. Plenty of possibilities at this point.
We will need some other clues and you will need to do some more testing.
You have to make sure there is fuel in the carburetor, or if fuel injection that the pump is getting fuel to the injector or injectors, or if you have spark at the plugs.

 

[paddycurr]

It's a new coil and I substituted a Pertronix III for the old points system, so no doubt I installed it wrong. Also had to replace the spark plug boot connecting the distributor to the coil, as the new Flamethrower III coil had a significantly wider mouth than the factory coil. Chances are good I didn't do a great job replacing that boot, either.

What's the best way to check the for spark? Run a multimeter on both sides of the coil to check for voltage? Take off the spark plug and see what's happening in the coil?

 

[DirtDonk]

First what do you have connected to the coil? Just two wires, three, or more?

 

[paddycurr]

Right now there's FOUR wires running to the coil, plus the coil spark plug coming from the distributor. The black Pertronix wire coming out of the distributor is on the negative terminal by itself. The positive terminal holds the other three: Red/Green 12 volt power source, Brown coil to starter sol wire, and the Red wire coming out of the Pertronix distributor set up.

 

[DirtDonk]

OK. Good so far I suppose.
Was just wondering if you had a tachometer connected or not. Sometimes those can cause problems.
Is the red with green wire running straight from the ignition switch or did you install the ballast resistor? In the case of the Pertronix they do not want the resistor in the circuit.
If it’s direct to the coil then you’re good to go.

Be careful checking for spark the usual ways. Pulling a wire and letting the sparks fly too close to the distributor can damage the module. Or at least it could with the first models. I’m not sure about the model 2, or 3.
I know you just said you ordered a new voltmeter, but do you already have a timing light?
Even though you can sometimes kind of get away without it, it’s very handy to have when you’re first starting up an engine.
I forget, is this just a re-wire? Or is there a rebuilt engine where you had to remove the distributor?
If so you’ll need to time it. And this is when a timing light really comes in handy.
But the other reason for a timing light is it a convenient way to check for spark on any of the wires.

Next thing to check might be a way to see if there’s fuel getting to the carb by pulling the air cleaner off, looking down the carburetor and rowing the throttle lever on the side of the carburetor back a couple of times.
Each time you do that you should see a healthy squirt of gasoline coming out of the accelerator pump nozzles.
If no squirt, then probably no start.

 

[DirtDonk]

One more thing while hunting down ignition gremlins. Temporarily disconnect the brown wire from the starter relay or the ignition coil.
It’s not a bad thing to have, but if somehow the starter relay is defective and causing trouble, it could be messing with things through that brown wire.
Probably easier to disconnect it at the starter relay, but if the coil is easier just do it there.

Just trying to isolate things at this point.

 

[DirtDonk]

Oh, and first time I ever heard of Venmo was last week!
So no worries for now and thanks for the offer.
We’ll figure something out but only after you get it running!

 

[fluffybunny]

After rewiring mine, it took a long time to get the carb primed. I installed a clear plastic fuel filter so that I could see when it started filling with fuel. Hopefully, priming it will get it running.

 

[Torkman66]

Just following along and have to add that DirtDonk, you are amazing! While the issues he is having are not super complicated, taking the time to answer in detail for a new DYIer and provide such great advice is truly appreciated. It takes a lot of time and some editing to get a good response developed and your input to original questions are very well done. I just want to thank you from the Bronco community for the time and effort you take! Thanks.