captainkim Posted August 4, 2019 Share Posted August 4, 2019 Hi tryi g to rewire the car after it fried. I can’t seem to remember where the black and red wires coming from the starter up near the shifter. Conan someone tell me where they connect to? I believe the red is the ground but the black I’m unsure of where to connect as there is nothing for it in this harness. Quote Link to comment Share on other sites More sharing options...
jhm Posted August 5, 2019 Share Posted August 5, 2019 Those don't appear to be OEM wiring (i.e. some previous owner put those in aftermarket); so you're really just going to have to trace them yourself and decide how to deal with it. If they were done correctly, the black should be a ground and the red would be a hot lead. Perhaps they are there for an accessory of some sort? Any OEM wiring for the starter should not be anywhere near the shifter, unless the car was originally an automatic perhaps? Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 5, 2019 Author Share Posted August 5, 2019 You’re correct. I traced the wire back and it’s from the transmission. I’m assuming reverse lights. Would you know what that black line connects to? Quote Link to comment Share on other sites More sharing options...
jhm Posted August 5, 2019 Share Posted August 5, 2019 What year and model is the car? And do you have the FSM for it? If not, you can download free FSMs at: http://www.xenonzcar.com/ If those two leads are for an indicator lamp, and they are still functional, you should be able to test them with a multimeter. The black would show ground, and the red would show voltage in a specific situation (e.g. when the car is in Reverse, or Park, etc). Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 7, 2019 Author Share Posted August 7, 2019 Ok. So I’m at a point where I’m ready to rip everything g out. Ive already shorted out my starter. As a novice ..would I be able to install a new harness myself? I was looking at Painless or Jegs. Is it a complete overhaul or is it cutting and connecting to new wires to fuse? They make it sound easy but wanted to get some advise. This car is a mess. I just really need to start over. I’m hoping these kits will be the savior. Quote Link to comment Share on other sites More sharing options...
Miles Posted August 7, 2019 Share Posted August 7, 2019 What year Z? Download a schematic for your car. There are many on-line. Some are in color. Download a Factory Service Manual (FSM) For example, the 1972 starter wire is black - yellow and it attaches to the solenoid "S" terminal Don't advise doing a re-wire of the whole car at this point. From the picture: has the fuse box been replaced? Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 7, 2019 Author Share Posted August 7, 2019 (edited) Thanks for the support. The car has a SBC and a T56 tranny. Im not sure how the PO did the wiring but it was a mess and sloppy which is why it burned. Does that make any difference? I almost feel like i have most of the wiring connected based on the harness connectors, but i have not idea what goes to the aftermarket fuse box and there is also a resistor. I have a 2/71 240z and bought a used harness from an older 71 based on the differences. I have the FSM but not sure if it would apply to the engine. None of my dash gauges are coming on or powering up. Is there a specific line i need to connect to power the dash? My headlight works, the flashers work and the key clicks when i turn it...however thats it. everytime i put the battery cable on , a fuse blows and its usually connected to the resistor. I dont even know what the amps should be on each changed the starter but its still the same, the battery is new. Any help is GREATLY appreciated, or if you can recommend someone that can fix it at my house...im in Northern NJ right by the NY Border. Edited August 7, 2019 by captainkim Quote Link to comment Share on other sites More sharing options...
jhm Posted August 7, 2019 Share Posted August 7, 2019 You're the only person that can make the decision whether to install a new harness or fix what you've got. It will depend on how bad the current harness is, how much time and effort you're willing to put into it, how much you want to spend on it, how long are you planning to keep the car, what other mods are you planning for the car, what is the desired outcome, etc, etc. My previous car was also an SBC conversion, that had been badly screwed up by multiple previous owners. I chose to fix it. It took a lot of time, but I know the electrical system inside and out when I finished. On my next car, I did a complete rewire because I knew that I would do it right, and I had already stripped the car down to a bare shell....so that was an easy decision. Quote Link to comment Share on other sites More sharing options...
Miles Posted August 7, 2019 Share Posted August 7, 2019 I had the same problem with my first 240Z. The PO butchered the wiring. Took me weeks to trace each wire he installed and put the wiring back to stock. Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 7, 2019 Author Share Posted August 7, 2019 thanks. I plan on keeping the car as long as i can....not planning on doing any mods. I just want to drive the car like it was before the wires fried....=) Thanks for the input.....I just ordered the Painless wire set....BUT...Im still not giving up. I have 5 days to figure it out before the wires show up and have to start from scratch. JHM.....I may need to drop by as a last resort!!!! Quote Link to comment Share on other sites More sharing options...
jhm Posted August 7, 2019 Share Posted August 7, 2019 The fact that it's a '71 kind of works in your favor....electricals in the early cars was a whole lot simpler than for the later years. If you have a buddy who's comfortable working with auto electrical systems, may be worth asking for his or her help with this. Buy yourself a good multimeter and test lamp....you're going to need it if you decide to fix things yourself. The "Engine Electrical" chapter in your FSM will define the correct wiring for starter motor, etc. The "Body Electrical" chapter will help you figure out the wiring for gauges....there is a separate harness for the dashboard ("Instrument Harness") that may be buggered up; or it could a simple matter of poor connections at the connector block. If you're blowing fuses the instant you connect the battery, stop. There are shorts somewhere in the system and you need to isolate those and rectify them before they cause a fire. Poor grounds are very often responsible for electrical malfunctions in these old cars. People will often find that an accessory is not working simply because the ground had corroded and just needed cleaning up. Good luck with it. Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 7, 2019 Author Share Posted August 7, 2019 Yes...the fuses short as soon as i connect the battery. The blown fuses are usually one of the 4 wires attached to the relay. Ive been asking around for any shop that can do this but unfortunately no can or wants to. Worse case....ill install the Painful painless wires ...hopefully i can find the short(s). I check the grounds. Question......Are wires still good if the cover is intact but the actual copper inside looks burned...or do they need to be replaced? I know the connection is there but does the burn cause less connectivity thus causing potential issues? thanks again Quote Link to comment Share on other sites More sharing options...
Miles Posted August 7, 2019 Share Posted August 7, 2019 (edited) The Painless install is documented throughout HybridZ and on the web. Suggest that you purchase a copy of the Jags that Run 240Z V8 conversion manual (link below). Buy the book How to Restore Your Datsun Z Car by Wick Humble. It will save you hours of searching for "how to" info. Suggest you buy a book on auto electrical wiring such as the one pictured below. Here are some links that may be helpful for your project: https://forums.hybridz.org/topic/29786-painless-harness-to-z-column-harness-headlight-combo-switch/ https://www.datsun-240z-upgrades.net/ http://zhome.com/ https://www.zcar.com/ http://www.classiczc...com/index.html/ http://www.zcarparts.com/ http://www.arizonazcar.com/ http://www.jagsthatrun.com/index.html https://jagsthatrun.com/products/jaguar-v-8-conversion-manual?_pos=1&_sid=5f8e0c2e4&_ss=r Edited August 8, 2019 by Miles Quote Link to comment Share on other sites More sharing options...
Miles Posted August 8, 2019 Share Posted August 8, 2019 Would like to see pictures of the engine bay wiring. Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 8, 2019 Author Share Posted August 8, 2019 My Painful wiring should be coming in tomorrow. I wish i could figure this out but electric is my achilles heel. not sure what pics of the engine wiring you want to see but maybe this will shed some light IMG_1100.HEIC IMG_1506.HEIC IMG_7128.HEIC Quote Link to comment Share on other sites More sharing options...
Miles Posted August 8, 2019 Share Posted August 8, 2019 1 hour ago, captainkim said: My Painful wiring should be coming in tomorrow. I wish i could figure this out but electric is my achilles heel. not sure what pics of the engine wiring you want to see but maybe this will shed some light IMG_1100.HEIC 1.43 MB · 3 downloads IMG_1506.HEIC 1.17 MB · 2 downloads IMG_7128.HEIC 1.35 MB · 5 downloads Can't open pictures. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted August 8, 2019 Share Posted August 8, 2019 On 8/4/2019 at 11:38 AM, captainkim said: Hi tryi g to rewire the car after it fried. I can’t seem to remember where the black and red wires coming from the starter up near the shifter. Conan someone tell me where they connect to? I believe the red is the ground but the black I’m unsure of where to connect as there is nothing for it in this harness. Back to the beginning. If you look at the wiring diagram, the reverse light circuit is tied to the Accessory bus in the fuse panel. The circuit also feeds the wiper motor. Out of the 20 amp fuse (stock) there's a Blue/Red (LR) that runs through the dash harness -> engine bay harness -> wiper motor. There is a Red (R) spliced into the LR at some point that also (stock) runs through the dash harness to the engine bay harness. Stock, the wiring to the reverse switch on the transmission comes out of the loom about the same spot the wiring to the wiper comes out and runs under the trans tunnel on the right side to the switch on the transmission. A Red/Black (RB) comes out the other side of the switch and back along the same path that the Red went out. Once it's back inside the cabin, the RB connects to the body harness and goes back as power (+12v) to the reverse lights. The lights get their ground from back under the hatch (tied to the sheet metal somewhere IIRC) In your case the red should be connected to that 20 amp fuse output that also powers the wiper motor. The black is NOT a ground (if it's coming from the other side of the reverse switch) - it should connect to the Red/Black that's going back to the reverse lights. (I would not do it that way - as it's confusing to anyone else working on the car. Black in a Datsun should always be a ground. If you can't run it RB, use R - then people will at least know it's probably power) (A switch is merely a break in a wire - it is NOT "one side hot, one side ground". So, in this case the Red/Black is just a continuation of the Red wire. The reverse switch is there so the light only comes on when the transmission is in reverse. The reverse switch breaks the wire apart when not in reverse, and "puts the wire back together" when it is in reverse.) This is a very simple part of the process. I just learned most of the above looking at the wiring diagram and remembering how the wires hook up to my transmission. (OK, I have a little stronger background in Z wiring, I admit...) But, If this is too much, you'll need to get someone else OR - like they stated above - spend a good deal of time in learning. IMO an EZWire kit will not make this process simpler but at least it will be new wire - which is always a plus... You'll still need to understand how all these components are wired - and why. The dash harness (there are actually two separate harnesses strapped together as one assembly) is mildly complex - gauges, lighting, multi-function switches, ignition, fuse panel, flashers, stop lamp, hazard switch (OK, now I'm just being an a-Hole...). How do you eat an Elephant? One bite at a time. This can be done - one step at a time. 1 Quote Link to comment Share on other sites More sharing options...
cgsheen Posted August 8, 2019 Share Posted August 8, 2019 I would disconnect that fuse panel from the console (trans tunnel) and lift it away from the sheet metal. Check to see if there's anything underneath that would be contacting the body. Nothing about that fuse panel should contact a ground source. No wires coming off it should be tied to ground. I'm wondering if the dash harness connectors that would go to the stock fuse panel are still intact. If so, an MSA replacement fuse panel could be used to simplify matters somewhat. Quote Link to comment Share on other sites More sharing options...
captainkim Posted August 8, 2019 Author Share Posted August 8, 2019 Wow. That was a lot of info. Thank you for all the advise. I think I’ll replace the wires regardless since they are so old. Quote Link to comment Share on other sites More sharing options...
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