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Old 02-12-2020, 11:22 AM   #1
MALIBLOC
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Burnt alternator wire-useable link

been having issues with truck and both the battery and alternator test fine when they are removed from truck but when they are running on truck the alternator shows no voltage at battery and the alternator test at 11 amps. After search I found a 10awg wore from Alt to ignition burnt at the connection at firewall.

Question is ,

Can I cut the wire back a few inches from connector and add a fusable link there and solve my problem Please see attached pictures.

I have all the correct grounds too
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Old 02-12-2020, 01:51 PM   #2
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Re: Burnt alternator wire-useable link

Your truck is quite a bit different than the 67/72 models. It didn't come from the factory with a fusible link, and I believe the amp meter had all the current running through it so you are going to be pulling all the current into the cab which might account for the burnt wire. I also think it came with a generator and I don't remember a 10 gauge wire anywhere in the harness. Some more details might be helpful. Like what mods have been done and how is the alternator wired. Do you have an external voltage regulator or is it inside the alternator?

Ray McElvoy Is the expert on the older years so maybe he will chime in and help us out.
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Old 02-12-2020, 03:47 PM   #3
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Re: Burnt alternator wire-useable link

I included my drawing above hope that helps. No mod's just a external fan on radiator, regular lights front and back-not even a radio.

I have a wire going from alternator to ignition switch (that plug is at the cab and my plan is to cut the red wire out completely or jump it somehow)
I have a wire going from battery to starter
I have a wire going from starter to ignition switch

The alternator I recently bought is a three wire from Oreilys with a internal regulator (exact replacement of what I replaced)

I just added grounds to the motor to frame and motor to cab (this past weekend)

I believe this problem happened because the motor was not properly grounded.

My question is what inline fuse size can I use to jump the area that is burned or should I run a new wire from ignition to alternator with some sot of external regulator. Which I currently do not have on this truck.

Thanks for any help in advance
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Old 02-12-2020, 04:38 PM   #4
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Re: Burnt alternator wire-useable link

Possible the connector burned due to years of corrosion.
BUT, you mentioned a radiator fan. Possible the draw from that overloaded the connector. A properly sized fuse/fusible link would keep a new connector from burning but would blow in the process, leaving you pretty much where you are now.

A lot of early vehicles had generators/alternators in the 30~40 amp range as that was all they needed. Add a couple of halogen headlight bulbs + a non-standard radiator fan and you are probably well over the original design limits.

Might want to consider getting a set of headlight relays plus a relay setup for the fan so the high current things are drawing straight from the battery instead of going through the existing harness.
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Old 02-12-2020, 07:27 PM   #5
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Re: Burnt alternator wire-useable link

Thanks dead Parrot , what's something I can put inline from my ignition to starter thats not going to fry the wire again.
Could that wire of fried due to not have grounds that I already fixed just a couple of days ago?
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Old 02-12-2020, 07:49 PM   #6
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Re: Burnt alternator wire-useable link

I just called the alternator CS line and they said that I can run a wire directly to the starter solenoid and that should solve my problem they just said to made sure there is a good connection to both and use a useable link.
I will try that , question is do I leave the original wire from the alternator to the ignition
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Old 02-12-2020, 08:58 PM   #7
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Re: Burnt alternator wire-useable link

Might want to mention what vehicle you're working on.
The connector was resistive, acted like a heater and burned.
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Old 02-12-2020, 11:18 PM   #8
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Re: Burnt alternator wire-useable link

1955 second series truck , after this alternator problem came up , I notice the motor had no grounds, so Im hoping that solved it , Im just curious as to why I don't have a wire going to starter or battery from alternator.
The picture shows how its wired now and the dotted line is what Im thinking of installing with a fuseable link ?

I called their customer service and its a 100 amp alternator with three wires that internally regulated. The rep said I should abandon the wire to the ignition from the alternator and have the new wire go from starter to solenoid and then solenoid to battery to charge it up and then the wire from solenoid to ignition to start of all the acc and ignition? there so many way I guess
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Old 02-13-2020, 01:11 AM   #9
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Re: Burnt alternator wire-useable link

Well, the wire from the alt to solenoid would go to the big solenoid connection leading to the battery. The wire from the ignition switch goes to the S-terminal on the solenoid.
Something still needs to power the low current sire of the system, which includes running the solenoid. The high current side is just the starter motor itself, controlled by the solenoid, which is controlled by the ignition switch.
Poor engine grounds are not good, but will cause less current (slow or no cranking) and therefore less heat rather than more. Simple Ohm's Law (OL). Ground the the battery to the engine w/ the big cable (high current). Anything running on electricity requires a ground. I'd use straps from the engne to the frame, and then frame to body parts. All current flowing from the source (battery or alt) has to flow back to the source. Again, see OL.
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Old 02-13-2020, 01:46 AM   #10
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Re: Burnt alternator wire-useable link

Thank you , I did run a new ground from engine to frame, and another ground from valve cover to body .

I ran a #10 wire from the alternator post directly to the solenoid and bingo, I now have 14.1-14.4V at the battery now, as for the burnt wire Im still trying to see why I would need a wire going from alternator to ignition?

I turned the lights on and fan went on and the current dropped to 13.6-14.00. Im going to check if the fan has a relay, Im sure it does but sure seems like a big draw and boy let me tell you the lights seemed brighter so I look forward to testing the truck in real world this weekend both day and night.

Im going to solder a fusable link before I hard wire everything this weekend, thank you to all that help so far. Unless you guys think I don't need a useable link from alternator to solenoid.

Last edited by MALIBLOC; 02-13-2020 at 01:50 AM. Reason: spelling
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Old 02-13-2020, 03:00 AM   #11
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Re: Burnt alternator wire-useable link

It sounds like you're measuring voltage, not current. That's fine, but understand the difference. Voltage is like water pressure, and current is like water flow.
To measure current, you disconnect something in the circuit and put the meter in series w/ the load.

Last edited by franken; 02-13-2020 at 03:12 AM.
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Old 02-13-2020, 10:55 AM   #12
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Re: Burnt alternator wire-useable link

Quote:
Originally Posted by franken View Post
It sounds like you're measuring voltage, not current. That's fine, but understand the difference. Voltage is like water pressure, and current is like water flow.
To measure current, you disconnect something in the circuit and put the meter in series w/ the load.
You've got that backwards, Voltage is like flow amperage is like pressure, resistance is what creates pressure.
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Old 02-13-2020, 06:08 PM   #13
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Re: Burnt alternator wire-useable link

Quote:
Originally Posted by biketopia View Post
You've got that backwards, Voltage is like flow amperage is like pressure, resistance is what creates pressure.

Perhaps you should do a little research.

https://search.yahoo.com/yhs/search?...896924%3Aup%3D


Current, Voltage and Resistance The flow of electricity through an object, such as a wire, is known as the current (I). It is measured in amps (A); if the current is very small then it is described in milli-amps (mA), 1000 mA = 1A. The driving force (electrical pressure) behind the flow of a current is known as the voltage and is measured in volts (V) (Voltage may also be referred to as the potential difference, or electromotive force). The property of a material that limits current flow is known as its resistance (R), the unit of resistance is the ohm (Ω). Resistance to alternating current is more properly called impedance but, in this application, resistance and impedance can be considered to be equivalent. The relationship between current, voltage and resistance is expressed by Ohm’s Law. This states that the current flowing in a circuit is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit, provided the temperature remains constant. Ohm’s Law: Current (I) = Voltage (V) / Resistance (R) To increase the current flowing in a circuit, the voltage must be increased, or the resistance decreased. A simple electrical circuit is depicted in Figure 1a. The flow of electricity through this circuit is further illustrated by analogy to the pressurized water system in Figure 1b. In the electrical circuit the power supply generates electrical pressure (voltage), equivalent to the pump creating water pressure in the pipe; the current is equivalent to the rate of flow of water; and the light bulb provides the resistance in the same way as the restriction in the water system. The ammeter is equivalent to the flow meter and the voltmeter measures the difference in electrical pressure each side of the restriction in the water system. There will be a drop in voltage due to the energy used up in driving the current through the light bulb, which has a higher resistance than the wire in the circuit. Similarly, the water pressure at (A) will be less than at (B). Figure 1a Simple Electric Circuit Figure 1b Pressurised Water System The overall resistance of an object depends on a number of properties including its length, cross-sectional area and the type of material. The longer a conductor, the greater its resistance; for example, a two metre wire has twice the resistance of a one metre wire of similar properties. The larger the cross-section of a conductor, then the lower its resistance: overhead power cables have a much lower resistance than a lamp flex of the same length. Different materials also have different abilities to conduct electricity. Metals conduct very well but materials such as ceramics or glass do not usually conduct electricity at all and are known as insulators. Animals contain a high proportion of liquid that will conduct electricity well; however skin, fat, bone and hair are poor conductors. Electrical current will take the path of least resistance through animal tissue, with the result that only a small proportion of the measured current will penetrate the brain. Animals with heavy fleeces, thick skin, fat layers or thick skulls will have a high electrical resistance. Table 1 shows how the relationship between current, voltage and resistance differs when stunning sheep of different physical condition. In this example, the minimum current required for an effective stun is one amp. Table 1 Examples of the application of Ohm's Law when stunning sheep Condition of Animal Dry, fat and in full fleece Wet, thin and recently sheared Voltage applied (V) 200 V 200 V Resistance across head (R) 1000 Ω 150 Ω Current (I = V/R) 0.2 A 1.3 A Result Ineffective stun Effective stun Next: Waveform and Frequency Back to top Introduction Electricity Current, Voltage and Resistance Waveform and Frequency Meat Quality Electrical Stunning Equipment Restraint Bleeding Safety and Maintenance Summary Download PDF Version Privacy Statement Humane Slaughter Association The Old School, Brewhouse Hill, Wheathampstead, Herts, AL4 8AN, UK Registered Charity in England No 1159690: Charitable Incorporated Organisation. Copyright www.hsa.org.uk. Website by adept
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Old 02-13-2020, 07:39 PM   #14
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Thumbs up Re: Burnt alternator wire-useable link

Stock GM vehicles:

There is no reason to have the wire going from the starter to the Alternator. No GM vehicle has this.
If you do then it will be hot all the time and shouldn't be. The starter get's it hot feed from the key switch.

As far as the fan and such use a few relays and wire them in to take the load off the whole system. This maybe what caused the burnt connection to begin with. To many amps being sent through the system that isn't rated to handle them.
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After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 02-13-2020, 08:19 PM   #15
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Re: Burnt alternator wire-useable link

[QUOTE=VetteVet;8677993]Perhaps you should do a little research.

Sorry, yes, I typed that backwards after a few beers. Current is flow, not voltage...
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Old 02-14-2020, 12:19 AM   #16
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Re: Burnt alternator wire-useable link

Quote:
Originally Posted by Andy4639 View Post
Stock GM vehicles:

There is no reason to have the wire going from the starter to the Alternator. No GM vehicle has this.
If you do then it will be hot all the time and shouldn't be. The starter get's it hot feed from the key switch.

As far as the fan and such use a few relays and wire them in to take the load off the whole system. This maybe what caused the burnt connection to begin with. To many amps being sent through the system that isn't rated to handle them.
Andy should I run the wire from alternator directly to battery then ? I don't understand , right now the alternator runs up to ignition then from there it goes to solenoid then to battery
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Old 02-14-2020, 10:21 AM   #17
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Question Re: Burnt alternator wire-useable link

First lets get some background from you. Year and model. I am assuming it's a early 66 are earlier model from your avatar picture.
This is a schematic for 60/65 Models.

Second picture shows the wiring I think you may have. It shows both points & Hei types. It for a 60/66 GMC but it should be the same for a Chevy.
Just trying to figure out what you are working with and what we need to start looking at.
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It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

Last edited by Andy4639; 02-14-2020 at 10:27 AM.
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Old 02-14-2020, 11:12 AM   #18
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Re: Burnt alternator wire-useable link

so the second image is close , as you can see by my drawing I posted above.
but I do not have the hot wire going from alternator to starter like the image suggest, I have a hot wire going from alternator to bulk head connector going to ignition.

I plan on running the 10 awg wire from alternator to starter like the diagram you have here so we are good now. there was never a direct connection like this diagram suggest

Last question is I have a 14awg useable link , and I think your diagram so that in the wire from alternator to starter, BUT could I just run a 15 amp fuse instead, I prefer not letting the "smoke out" if you understand what I mean.

my alternator is 100 amp does that mean that usable link or 15 amp fuse will blow all the time?

Sorry for all the questions, but your help is very valuable and appreciated
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Old 02-14-2020, 12:03 PM   #19
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Re: Burnt alternator wire-useable link

To make future wiring simpler, get one of these junction blocks from a 90's era Chevy PU. This was about a $5 item with the wires from the local Pull-a-Part. It will keep the wiring around the starter much simpler then using the starter/solenoid as an impromptu junction block.

One of the large red wires is the alternator wire complete with 12ga fusible like so that implies the red wire is 8ga. Since yours is an 100amp alt, I would go with at least an 8ga.
Another advantage of these is they come with an assortment of factory assembled ring ends + fusible links + a random length of wire. (At least that is how the Pull-a-part here lets it work).

If you switch both your headlights and radiator fan to relays that draw their power from this block, then your existing dash wiring will likely work pretty much as is, once you fix the burned connector and wiring. Most of these blocks include a fusible link sized for 15 ~ 20 amps you could use to power your dash. Run the Alt, accessory battery wire and hot side of the solenoid to the block as well. Main battery cable still goes to large solenoid post.
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Old 02-14-2020, 03:37 PM   #20
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Re: Burnt alternator wire-useable link

Well like Andy said above, we need to know what system you have for the dash wiring and then we can recommend the best way to tell you how to wire your truck.

Like I said in a previous post, the 55 came from the factory with a generator and voltage regulator and it had an amp meter that had all the current flowing through it from the generator back to the battery. The feed wires were routed off the main lines like the diagram below.

Name:  ampguagediagram-ga18.jpg
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Later on GM replaced the generator with an alternator like the one in the diagram, I believe it was in 58 or 59. Then in 1962 they did away with the full flow amp meter and went to the battery gauge. It only has a very small current flowing through it so the circuit is much safer from fires due to shorts.

When your truck was modified and the internal regulated alternator was installed, it probably wasn't wired correctly so it wouldn't charge.
If the amp meter was replaced then I can show you how to wire it, but the best way is to get a junction block like Dead parrot recommended and showed.

Here is the way I modified a diagram to show a good way to wire it.
the alternator is a newer CS model but the alternator can be easily wired using the SI model that you have.


Name:  modified Wiring2.jpg
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The alternator output wire feeds the main junction which feeds the battery and the rest of the truck circuits. It also allows the battery to feed the circuits with the engine off. It also allows the battery gauge to work as intended, but if a volt meter is used then the battery gauge is not needed.
The key switch is wired from the alternator terminal and back to the alternator exciter terminal and it must have a 10 ohm resistor in series with the alternator for the SI and 100 to 300 ohm resistor with the CS that's shown.
The key switch will still have the ignition and accessory circuits but they are not shown in the diagram.

I hope this helps you.
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Old 02-14-2020, 08:44 PM   #21
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Talking Re: Burnt alternator wire-useable link

Dang man I must need to start wearing my glasses. I would have sworn your avatar picture was a 60 model truck!!!

I just looked again it's a 50's model. ?????
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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old Yesterday, 09:44 AM   #22
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Re: Burnt alternator wire-useable link

Thank you both
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Old Yesterday, 10:11 PM   #23
MALIBLOC
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Re: Burnt alternator wire-useable link

So I went and bought 8g wire to run from Alternator to starter solenoid but for the life of me I could not find a 12g fusible link , I went to 5 different locations and everyone had on 14g. So in my search I found this amazing place called ORVACS Electronics and I found this to use instead my question is what terminals do I connect to , Im assume on the load side would be the starter and the battery side would be the Alternator??
This thing cost 14.99 so it wasn't cheap or expensive and could be a fail safe incase the starter tooth gets stuck in gear??
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Last edited by MALIBLOC; Yesterday at 10:12 PM. Reason: spelling
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