connecting power without a starter

[Chazwars]

I just replaced my alternator but I do not have the starter (going to upgrade). Can I connect the alternator and pass current to check the rest of my electrical while waiting for my replacement starter or do I need the starter to take some of the juice?

[azruss]

The starter only runs when starting the car. The power from the battery goes to the top lug on the solenoid and then on to the alternator. Should be okay if you hook it up to the right wires. Are you planning on push starting the car to test the alt.

[Chazwars]

Woohoo! I ran the black wire from the battery to the alt, yellow to the relay (connected directly to the indicator wire) and the other black to the fuse box and boom 'black to battery' caught fire. I'm talking fire extinguisher level. Upon review, I had the fuse box black against the housing of the alt, the 'black to the battery' on top of the other black, and then the nut tightening the two wires to the housing. I did not have a stater connected and wires were taped up.

I don't think I want that to happen again and embarrassingly post for others not to do.

[wizard124]

Woohoo! I ran the black wire from the battery to the alt, yellow to the relay (connected directly to the indicator wire) and the other black to the fuse box and boom 'black to battery' caught fire. I'm talking fire extinguisher level. Upon review, I had the fuse box black against the housing of the alt, the 'black to the battery' on top of the other black, and then the nut tightening the two wires to the housing. I did not have a stater connected and wires were taped up.

I don't think I want that to happen again and embarrassingly post for others not to do.

I just posted to your starter/brown wire thread.....this is a bit of a duplication. I hope you take heed before your car catches fire!

Get a wire diagram for your year spider. If you don't understand it, then slow down and get help and ask questions!
A black wire usually means a ground wire, but not always! That heavy black wire (for my '80 anyways) that connects between the alternator and the starter is not ground! Those are positive connections! The ground for both the starter and the alternator are through their housings not any attached wires or plugs.

I don't know exactly what you did but it sounds like you connected those wires into a big short.

[Chazwars]

Yep, I'm following artigues diagram for a 72 to a t. My black (positive) from alternator to battery is actually red so that helps. Just to review. The red from my alt to battery fried. The black that runs to int on the ignition switch was fine but resting directly against the alt housing. The red was on top of that wire and then spacers and nut to secure. This as all connecting to the longest of the studs coming out of a Bosch 65a.

[wizard124]

it seems to me that a black wire from the ignition switch will be hot at some point. with it resting against the alt housing, likely caused your short. I don't have a 72 wiring diagram so I can't say for sure.

Re-check yours. Should the battery positive be wired direct to the starter stud?

[Chazwars]

it seems to me that a black wire from the ignition switch will be hot at some point. with it resting against the alt housing, likely caused your short. I don't have a 72 wiring diagram so I can't say for sure.

Re-check yours. Should the battery positive be wired direct to the starter stud?

Diagram shows black to ignition switch and black straight to battery. So, should I put a nut or something between the wire going to the switch and the housing and the wire going to the battery against the housing? Essentially the only output off the alt is the black going to the ignition switch, right? I checked that wire and it did not appear to be affected. Also, I wondering if I should increase the gauge size to a 6 or 8 for the wire betwwen the battery and the alt. One thing I am certain of is that a fuse is going betweenthe alt and battery before I test it out again.

[wizard124]

it seems to me that a black wire from the ignition switch will be hot at some point. with it resting against the alt housing, likely caused your short. I don't have a 72 wiring diagram so I can't say for sure.

Re-check yours. Should the battery positive be wired direct to the starter stud?

Diagram shows black to ignition switch and black straight to battery. So, should I put a nut or something between the wire going to the switch and the housing and the wire going to the battery against the housing? Essentially the only output off the alt is the black going to the ignition switch, right? I checked that wire and it did not appear to be affected. Also, I wondering if I should increase the gauge size to a 6 or 8 for the wire betwwen the battery and the alt. One thing I am certain of is that a fuse is going betweenthe alt and battery before I test it out again.

I took a look here: http://www.artigue.com/fiatcontent/Wiring_1969_1973.pdf
This shows heavy black wires from the POS battery terminal directly to #30 on both the alternator and starter. If you only have a light wire between the alternator output stud and the ignition switch, then you need to add the proper wire. on my '80, there is a heavy wire that connects the #30 terminals of the alt and starter solenoid. These stay hot regardless of the key position.
It also shows a thinner black wire running off the #30 alternator stud to the 30/1 terminal of the ignition switch. This wire will also stay hot as long as the cable(s) are connected to the POS battery terminal.

If you connect that #30 terminal black wire to any housing, you will create a short! I recommend you stop what your title suggest you are trying to do. Use a multimeter to make sure the new ignition switch is wired correctly. Repair your starter and have it bench checked by an auto parts store.

It is a tedious task to work through a wiring diagram. go slow. take notes. Once it is right, then reinstall the starter and have a go. Remove that brown wire fix.