I had some damaged wiring coming out of my alternator, so I re-wired it. For those of you who have been in the wiring, here is what I did... My battery is in the back now, so a positive wire runs from the starter post to the battery in the back. This is 1 ga welding wire...(big). A smaller wire attaches to the same post on the starter and goes to the back of the alternator. There is a splice in the amid this connection that goes to a plug on the right side of the engine bay, right near the fuel lines. The original wiring had a black cylinder at this splice. I eliminated this black cylinder (about a centimeter in diameter) and just used a splicer, heat shrink, and solder. WAS THIS CYLINDER SOMETHING IMPORTANT? I'm having charging problems now, but it is not ground related nor is it wire size related. Is this cylinder located near the plug called a fusable link or ???. I am at wits end with this. I have a stock alternator that tests good. The battery is a red top optima. Thanks for your help! -Jerod

 

That does sound like a fusable link. It's basically a section of smaller gauge wire designed to melt and cut the circuit if it gets too much current through it. The black part is just an insulator designed to bubble up when that happens so that you can tell the link has gone up in smoke when it does happen. You can buy replacement links at an auto parts store.

 

Jza, thanks for the reply. If this is a fusable link, does it have a purpose other than to act as a fuse? I am having charging problems as mentioned. Could it be a resistance or something that helps control alternator? Also, can someone check their car for me and tell me where exactly the fusable link goes. Is it in between the starter post and the plug splice, the alternator and the plug splice, or on a wire going to the plug? Thanks -Jerod

 

It sound like it was a fusible link. If you used a higher gauge wire (that 1ga you mentioned) to go all the way to the back of the car you may have increased the resistance to the point the car is wasting a lot of charge trying to push electrons down that big wire to your battery. A normal very long postive battery wire would have been sufficient. A local radio shop could fab one up for you. They buy the stuff by the roll.

 

No, buddy, I think you have it backwards. Resistance is directly proportional to length and inversely proportional to wire crosssectional area. Therefore, using bigger wire reduces resistance in the wire. Thanks for the reply!

 

Okay, after some thinking, I'm not sure if my circut design is actually allowing the battery to be charged. Here is the layout of my alternator/battery/starter circut vs. the factory circut. Can someone tell me if the alternator wire in the top diagram is charging thebattery or is the current flowing both from the battery and from the alternator to power the resistor (accessories)?

 

You're correct. I forgot the inverse proportionality rule for the wire cross-section. I thought it doubled too, not halfed. Anyway, I'd run the wire from the alternator directly to the battery. Looks like you have it going thru the starter. Also check that you have a good ground close to the battery.

 

Well yes that black cylinder you were talking about was a fusible link. Replace if it is bad.
And, the bigger the wire the better. I have never heard of too much resistence from too big of a wire. Just not logical. Unless your wire was wider than it was long, I dont think you will have any problems, and thats taking 2 miles wide and 1 mile long. And after all of that, it would have to be solid core.
Anyways, I would check your ground. I hope you are not grounding all the way back to the original spot, cause that would be bad. If not, ground to the frame somewhere.
Let us know.

 

I eliminated mine... (Hope this isnt bad!)

The ground should be great, but in order to make sure I tried doing the following.... The battery is grounded to the rear subframe. The engine is grounded to the A-frame bolt. Subframe connectors run along the car of course. Thinking that I WAS having grounding problems because of the non-charging condition, I ran an extra 1 ga. wire from the back bumper where the battery grounded over to the A-frame bolt where the engine grounded. This should have all points covered double. (I didnt remove the connections to the frame, just bolted in another loop to each point) I went ahead and ordered a low amperage/high torque mini starter and a 140amp alternator conversion kit. I'm gonna get to the bottom of this one way or another... -Jerod

 

Oh, the wires just junction at that starter's post....it's not actually going "through" the motor's coil. They are virtually in parallel configuration... Thanks! -Jerod

 

The fusible link is actually the short small diameter wire coming from the black cylinder - the small wire fuses open at a given current value, preventing the large diameter feed wire insulation from melting, shorting, and potentially causing a fire. The black cylinder itself is an insulated junction point for the alternator charge wire, battery feed wire, fan power fusible link wire, and ECM / fuel pump power fusible link wire (depending on year / engine). There are three other fusible links (short small diameter wires coupled to large diameter feed wires) attached to the large lug on the starter. They feed the alternator field, light system, ignition switch, & blower high speed relay.

 

Woooah, that really straightens it out! Thanks! :hail:

That being said, I gather that the fusible link will NOT effect the function of the charging system, only protect it from failure (fire) if too much current is put through it. Therefore, I'm gonna go ahead and try the 140 amp alternator kit to see if that will cure my charging problem. I can only guess that the additional wire length is just too much for the stock system to overcome. Any thoughts? Like I said, the grounding system is redundant and should be overly sufficient. I will also add a ministarter just for kicks, and it too will demand less cranking amperage supposedly. Thanks -Jerod

 

What exactly is the charging system not doing? Voltage too low (< 13 volts) only @ idle, or always with the engine running? Do you have an under drive pulley set installed? If so, you will need an over drive (smaller than stock diameter) pulley for the alternator.

 

To be honest, I havent found the reason why I'm having problems. Here are the symptoms:

At times, the voltage runs right at 12V, and at other times, it's running about 13V. This voltage variation seems not to vary with rpm. I do not have the underdrive pullies installed.

Completely randomly (more frequently when hot) the car will not start. The starter chugs. Sometimes waiting a few seconds, it will start right up. Anytime it chugs and wont start, I can just jump it and it starts immediately. I know it sounds like a grounding problem but it simply cant be Thanks for any help you could offer! -Jerod

 

When I relocated my battery to the rear, I ran a large (4 gauge, I believe) wire from the negative terminal on the battery to a bolt on the transmission to complete the starter ground path, in addition to the small 12 gauge wire from the negative battery terminal to the chassis at the rear of the car. The only ground path between the chassis and the block (starter), otherwise, is the small braided ground strap between the passenger side cylinder head and the fire wall.

 

Yes, I was going to say something about that braided wire you were talking about. I have had problems with that P.O.S. braided wire. It melted a couple of wires (luckily ones I no longer use), and then finally broke in half. I just replaced it with a 4 ga. wire, no problems yet. Also mine went from the fire wall to the distributor clamp down on the intake manifold. Maybe you can try that, but it also sounds like your voltage regulator might be giving you flack also. Hope that helps.