Does starter have to be hooked up to power the rest of truck?

[vikingsandpintos]

UPDATED>>> SCROLL DOWN! Quick version... Does the starter have to be bolted on and hooked up to get power thru the rest of the truck?

Long version.... Been working on my daughter's first vehicle, a 67 C10. Been doing a lot of various projects on it. A couple of weeks ago she put a new radio in it, and had it working. The headlights and tails haven't worked since we got it last fall, but some of the dash lights worked, and it started and drove.

I looked at various parts of the wiring, and it had been cut and spliced in multiple places under the hood and going back to the tails. I ordered a new harness going from the firewall to the rear, and a front light harness.

About a week ago, I pulled the trans out, because we are changing it from a manual to an automatic, but the new one isn't in it yet, along with the starter.

Also last week, since the radio is all done, she changed the dash pad, and pulled the dash stuff to get to it. While in there, we changed the headlight switch since it was there, and we didn't know if it might be a source of problems for the headlights not working.

Now, to today.. I didn't want to tackle the trans by myself, so I decided to work on the wiring. I changed the harness going to the rear. I changed the front light harness which includes the voltage reg, ect. I also put a new regulator on while I was doing the new harness. I put new battery cables on it. I ran extra grounds from the engine to the frame, and from the frame to the core support, to make sure everything is grounded really well. I didn't hook up the wires going to the starter since it isn't on yet.

As a side note, the distrib has been changed to an HEI by the previous owner. The old starter had 3 wires going to it, the big one from the battery, a small going to the S term, and a small to the R terminal. In another post, I asked about how to wire the new starter that only has the big post, and 1 small S terminal, and was told to use the old S wire to the new S terminal, and leave the other small wire unhooked.

Anyhoo, I got all the new harness and grounds done, and thought, I want to see if this fixed the lights! I put the battery in it, and hooked up the cables. I ziptied the starter wires and the other end of the battery cable so it couldn't touch anything. Tried the lights, and had nothing. In fact, there was nothing anywhere! No dash, no radio, no wipers, nothing, just completely dead! Double checked the battery, it was up. Tried a test light from the positive terminal to a frame ground, and it lights up.

Does the starter have to be hooked up for everything else to work? There is a red wire from the new headlight harness that is hooked into the battery cable, I assumed it goes thru the firewall junction box, and would power everything else. I don't see what the wires at the starter would have to do with anything, but wiring isn't exactly my strong point! lol

If the starter doesn't HAVE to be hooked up to try the other stuff, where do I start looking for the problem? We didn't do anything with the ignition switch, not sure where I should even start.... Usually, I follow the golden rule of changing 1 thing at a time, make sure everything is good, and moving onto the next thing. But in this case, have changed a lot of stuff since I knew the radio, ect, worked.

Any thoughts are greatly appreciated!!

[RGT]

There should be a wire coming from the positive side of the battery that connects power to the truck, it goes over to the passenger side fender and then up and over the radiator support.

[Cmercertx]

Originally Posted by RGT

There should be a wire coming from the positive side of the battery that connects power to the truck, it goes over to the passenger side fender and then up and over the radiator support.

I've had the same issue. That short section of wire from battery to fender is actually a fusible link. It's lightweight aluminum wire that is designed to burn up in the event of an overload. But the insulation will remain intact and you might not notice. You can buy a replacement or put some 10g wire with a 30 amp fuse in its place.

[VetteVet]

Here is a very simplistic diagram of the power circuit in our trucks.









Looking at the top left of the diagram is the battery showing the positive post and the fusible link to the fender junction, and then the power wire going down the left side actually it is the one that runs across the top of the radiator. Where it joins the other power wires to the voltage regulator, the alternator and the power wire to the cab. Shown on the bottom of the diagram going to the firewall block and into the cab.




On the other side of the block is another junction of power wires from this wire. They run to the horn relay, the headlight switch to power the headlights, down to the fuse panel, and one goes to the ignition switch.




You can't see the headlight switch or the ignition switch in that diagram, but follow the red wires on the top of the diagram and the two at the bottom right and the bottom center of this diagram, and you'll see the red wires going to the headlight switch and the fuse panel. These are the main power wires in the truck circuit.

coming off the headlight switch should be a 12 gauge blue wire that runs to the dimmer switch with power to the headlights. It connects through the dimmer switch to the tan and light green wires that go back through the firewall block to the headlights.

['68OrangeSunshine]

A couple of things I can think of, right off.
If you have a new harness for AT, then there's a Neutral Safety Switch in the circuit. W/o a tranny the NSS is open. [Unless jumped.]
Usually there's a big [Red] 4 - 6 ga wire from the Pos Batt terminal to the Starter, and the Purple wire to the passenger side terminal, The other Yellow 20 ga line from the bulkhead connector and thru to the Coil is deleted in HEI mode. [It was connected to the resistance wire for points, and you want full voltage for HEI.]
You need to comfirm the Fusable Link from Batt Pos. to the Fender Terminal [where it picks up the circuit from the Lighting Harness] is intact and carries continuity. Nothing works without this connection. As Cmer. said.
If this is your first 1967 Chevy truck, then you need to know that the ''Parking Lights'' go out when you select Headlights on the 2nd click. They do come on with the 1st click. That's normal. The Feds made the Big 3 change up to "Running Lights" and Side Marker Reflectors in 1968 MY.
Did you get a wiring harness and headlight switch specifically for a '67? Or were they generic?

[vikingsandpintos]

Thank you for all the replies! Yes, it is a harness for 67 truck, from Brothers. All the wires matched up to the original wires. The small red one by the battery has a round terminal end, so I ran that directly to the battery. The old harness, they had that wire scabbed into the positive battery cable too. I'm not sure what the fuseable link wire is, there was nothing like that on the truck, and no junction block. It had been changed to the HEI, so I assume the PO eliminated that and the coil.

I will have to do some testing with the light and see what is going on. Those color wiring diagrams should help! I don't know what it could be till I start testing, everything seemed to go together well. Hopefully this next weekend I can get back into it!

['68OrangeSunshine]

Originally Posted by vikingsandpintos

Thank you for all the replies! Yes, it is a harness for 67 truck, from Brothers. All the wires matched up to the original wires. The small red one by the battery has a round terminal end, so I ran that directly to the battery. The old harness, they had that wire scabbed into the positive battery cable too. I'm not sure what the fuseable link wire is, there was nothing like that on the truck, and no junction block. It had been changed to the HEI, so I assume the PO eliminated that and the coil.

I will have to do some testing with the light and see what is going on. Those color wiring diagrams should help! I don't know what it could be till I start testing, everything seemed to go together well. Hopefully this next weekend I can get back into it!

HEI conversion should be irrelavent to a fender junction block, but who knows what goes on in the minds of POs? He may have deleted it, thinking that he was streamlining the circuitry.
The Fender Terminal Block is available from at least these 3 sources:
LMC: "Battery Junction Block", p/n 36-2505, $9.95.
Brothers: "Positive Lead", p/n TJB7200, $7.99.
RockAuto: "Junction Block" [Goodmark] p/n GMK4143374672, $5.36.

The Fusible Link is a Dorman product: "16 Ga. GM Fusible Link Wire", p/n 85621, $4.49. Should be available from any local parts store.

It connects from the side of the Battery Positive cable lug and is bolted to the contact on the fender terminal block, mating with the ring terminal end of the front wiring harness. There's a 1/2" hole in the fender for the terminal end to emerge from under the fender sheetmetal to make this contact.
Not having a fuse or fusible link in-line from the battery, could cause the front wiring harness to burn up if there's a dead-short.

[vikingsandpintos]

I have an update!

I had a few minutes to kill waiting on someone that was stopping by, so I got the testlight out... Unplugged the regulator, had power at the red wire there. Checked the red wire at the alt, had power there. Got under the dash, nothing at any of the fuses. Checked the plug where the front lamp harness bolts to the firewall, and I guess I didn't have it tight enough!! lol I tightened it, and what do you know, POWER!

Don't worry, I kicked myself for it!! But I did feel much better about the whole situation. And I am going to order that fuseable wire and junction for safety. PS If anyone has a pic of where and how that looks that would be great!!

So now my next question, I will ask here but if I don't get replies I will start a new thread. I now have taillights! I also have front lamps! But, no headlights...

If I pull the headlight switch out 1 notch, the front lamps come on. If I pull it 2 notches, the front lamps go out, and still no headlights. I checked for power at the headlight plug just in case both headlights were burned out, but no power at the plug. Any suggestions before I start poking around under the dash? (Remember, it does have a new headlight switch in the dash)

Thanks again for all the help, I love this forum!!

['68OrangeSunshine]

OK.
Unless invisible aliens are sucking the life out of your headlight system, it could be both headlights are blown/burned out.
[This is a Chevy, not a GMC, right?]

If you don't own a Volt-Ohm-Milliammeter [VOM], get one. They're less than $10 at Harbor Freight [and they sometimes give 'em away].

Disconnect the harness plug at the back of the bulb, and run a VOM on Ohms across both outside brass tangs, then across the inside tang and each of the outside tangs.
In each case, you should read 0 Ohms on the meter with a good filament. If the meter reads infinity Ohms [or doesn't move if a needle type] then that bulb is shot.
Called a 'continuity check'.
If the headlamps checked good, then switch your VOM to volts '20 vdc range' , with the headlamps ON, put one test lead spike in one slot and then one in the other. [Flip them if it reads (minus) - 12 vdc.] If it reads +12 volts, it's getting power. If the voltmeter reads 0 vdc, then there's a break in your headlamp wiring.

If all else fails, recheck the connections at the headlamp switch, and the Hi/ Lo brights relay.
Also be sure the ground connection from the front headlamp harness is connected to the radiator wall, in front of the battery. Might be hehind the Batt tray.
Brothers sells the M&H Wiring line. That's what I use. It's first class OEM-style Americam-made, and each harness is signed by the guy who built it. Never had BO stuff from them myself, but who knows?

For a '67, the Parking lights should go OUT on the 2nd click, and the headlights ON.

BTW. Did you put a fuse or fusible wire between your headlamp harness and the 12VDC hot terminal yet?

[Moose Monkey]

Great info. Any power at dimmer switch?

[vikingsandpintos]

Sorry about bringing back an old thread, but was looking for the info on the starter wiring and saw I never updated the headlight issue I was having.

It turned out to be the dimmer switch was bad. Once that was changed, headlights work correctly. And I have put the fusible link and junction block on the truck. now to get the truck to start while cranking, I'll be good! lol

['68OrangeSunshine]

It's not a zombie thread problem unless it's years old and most of the commenters are dead or had their accounts suspended.
Good, that you cleaned up your wiring.
You'll get better results and more viewers if you start a new thread like Truck Won't Start, or something. Also better informed advice if you post it in Engine and Driveline.
The guy that helps me tune my truck is from Battle Creek.