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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2008 Posts: 36 New Guy | | New Guy Joined: May 2008 Posts: 36 | It's been a while and I have a new question. I recently purchased a replacement harness from Patricks as well as an alternator and DA Plug. I have installed the wiring per the instructions but am having difficulty understanding the flow of power to the lights. The way I understand the flow based on the wire harness numbering is: battery connects to - amp meter terminal, + amp terminal connects to alternator stud, one wire (14 gauge?)of DA connects to one ignition switch terminal, second ignition terminal goes to coil, third terminal connects to headlamp switch with 10 gauge wire. Does the wire from the DA plug send power to the ignition switch? It seems to me that I need to power the ignition switch from the alternator terminal stud or battery using a wire at least equal in size to the headlamp switch wire or I could run a power supply to the lamp switch.
Have any of you installed this same harness?
Thanks,
Josh '54 3600
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Josh, Stuart (atomarc) and others will chime in with helpful advice. If you are able to post a photo of the installation diagram you received (especially for the alternator), more will be known about your harness. By the way, you are mixing vendors: Patrick's Antique Cars & Trucks Chevy Duty is no more. It is now called: Classic Parts of Americabattery connects to - amp meter terminal, + amp terminal connects to alternator stud, one wire (14 gauge?)of DA connects to one ignition switch terminal, second ignition terminal goes to coil, third terminal connects to headlamp switch with 10 gauge wire.
Does the wire from the DA plug send power to the ignition switch?My guess is that the wire (or, one wire) from the DA switch is used to "excite" the alternator and trigger it's charging. (a one-wire alternator is wired differently and behaves differently, but you most likely do not have a one-wire alternator) Tim | | | | | Joined: May 2008 Posts: 36 New Guy | | New Guy Joined: May 2008 Posts: 36 | The harness was purchased from Patrick's but apperently supplied by Classic Parts based on the "Chevy Duty" printed on the directions. There is no diagram of the system only directions calling for numerically identified wires to attach to terminals. I believe that I have followed the directions correctly and I am fairly well versed in things mechanical and electrical. The above listed flow of power is based on the wire numbering scheme provided with the harness andI believe accurate. I was hoping that someone else on this site had purchased the same harness and could clear my confusion.
Josh '54 3600
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | I have used the 1954 Chevy Duty harness for an alternator and a kit for a generator. My alternator was a one-wire alternator. It sounds like your is not.
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I haven't used any of these kits because I made my own. However, your description definitely sounds like something is mixed up. The alternator can put out a very hefty current and therefore it has to have a fairly heavy lead. | | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | Josh,
Since no one has posted anything, here are some guesses (beware):
+ amp meter terminal connects to: alternator stud This should be a fairly hefty wire - this brings the charge from the alternator to the Ammeter.
battery connects to: - amp meter terminal This should be a fairly hefty wire - this one gets the charge from the Ammeter to the battery.
one wire (14 gauge?) of DA connects to one ignition switch terminal This is the "exciter" wire - it signals the alternator to start charging. (This wire is not needed/used/found on a one-wire alternator, which "self excites" at 800+ RPM.)
second ignition terminal goes to coil This is your ignition lead.
third terminal connects to headlamp switch with 10 gauge wire If you are referring to a third ignition terminal, this might be a power lead to the light switch?
Are there other leads from the DA plug? (I think that one might be to a dummy light - an indicator light?)
I am not confident that my guesses are correct - where is Stuart?
Tim
| | | | | Joined: May 2008 Posts: 36 New Guy | | New Guy Joined: May 2008 Posts: 36 | There is a second wire from the DA plug and it connects to the alternator stud.
I agree that the 10 gauge wire is the feed to the lights. The problem is that there is no power supply to the switch meaning no power to the coil, gas gauge, or lights. My temptation is to run a wire either from the battery or the positive side of the ammeter to either the light or ignition switch. I'm trying to avoid a potential short that I might be missing.
Josh '54 3600
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | You need to know for sure before hooking this all up. If you look at the original diagram the new harness should accomplish all that the original did, at a minimum. | | | | | Joined: Oct 2008 Posts: 121 Shop Shark | | Shop Shark Joined: Oct 2008 Posts: 121 | Just received a wiring harness from Classic Parts of America for my 55 second series. Spent a couple hours this afternoon trying to figure out what I had, where it was going and removing the rats nest of splices and dead end wires from the previous owner(s). The directions are somewhat confusing and with the help of my assembly manual, was able to figure it out. Missing some connectors and emailed Classic with hopes they will ship them out. All in all, it appears to be a quality kit with the right color coding and lengths.
1955 Chevy 3100
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