BabeTheBlueOx Posted January 16, 2023 Share Posted January 16, 2023 Hi All, The wiring on my bullnose is a mess. Someone was in it at one point and left a rat's nest of wires and inline fuses. Whenever something quits working I chase down bad grounds, wire breaks, fuses in odd places, basically all the "stuff". I was reading about relocating the fuse block in Gary's writeup, and am wondering what size lift it would be to locate a fuse block in the engine bay and rewire one circuit at a time into the new circuit block. Just bypass the existing wiring a little bit at a time until it's all gone. It can't be too complex on a carbureted engine, right? Lights, ignition, distributor, wipers, alternator, radio, a few dash indicators, etc.. etc.. It seems like it will be a lot less work than trying to trace and patch together the existing circuits. Thoughts and experience? Link to comment Share on other sites More sharing options...
81-F150-Explorer Posted January 16, 2023 Share Posted January 16, 2023 It depends on your skill level. I've done complete re-wires of vehicles. I find it easier to take an existing wiring harness, take it out of the vehicle, unwrap it, and repair one circuit or wire at a time on my table. With the right connectors, terminals, plugs, and tools you can repair an existing harness to like new condition. I had a busted/broken fuse panel as example, and all it took was 30 minutes of transferring the wire terminals from the broken one to the new one, and putting the fuses back in place. What I would do if this was my project. I would get a reputable wiring diagram for your truck, remove the problem harnesses completely from the vehicle, un wrap the harness, and get rid of all the aftermarket stuff attached. Then I would test each color wire individually with a multimeter set to ohms, and then repair each wire that had a problem. Once the wiring was fixed to factory specs, then I would add back the extra circuits you need or require, the proper way. For me, redoing a whole new Power distribution system would be a lot harder for me to do than repairing and fixing the old one. But each person is different. P.S. Whatever way you chose, I would not recommend replacing just one circuit at a time, knowing there are other issues with other circuits. One section of harness at a time, yes, but one circuit at a time could cause unforeseen issues, and some that could be dangerous. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 16, 2023 Share Posted January 16, 2023 That's an interesting question. And you will probably get several very different answers. In fact, you might get more than one answer from me. First, what you linked to is what I have planned to do for Dad's truck, but haven't done it yet. However, I've done that an more on Big Blue. I used an identical power distribution box on Big Blue's passenger's side and put the circuits shown in it. However, it turned out that the Bosch cube relay is not strong enough to pull in the PMGR starter that I have and started giving problems. So I rewired and went back to the standard fender-mounted relay for the starter. But I kept the fuses replacing the fuse links. Later I converted to EFI and put a similar power distribution box on the driver's side of Big Blue, and it has things like the fuel pump relay, EEC relay, etc in it. And now to your question. I guess it depends on where the problems are with your wiring. If the issues are downstream of the fuse box then I don't think changing would help. So, where are the problems? Link to comment Share on other sites More sharing options...
ratdude747 Posted January 16, 2023 Share Posted January 16, 2023 It depends on your skill level. I've done complete re-wires of vehicles. I find it easier to take an existing wiring harness, take it out of the vehicle, unwrap it, and repair one circuit or wire at a time on my table. With the right connectors, terminals, plugs, and tools you can repair an existing harness to like new condition. I had a busted/broken fuse panel as example, and all it took was 30 minutes of transferring the wire terminals from the broken one to the new one, and putting the fuses back in place. What I would do if this was my project. I would get a reputable wiring diagram for your truck, remove the problem harnesses completely from the vehicle, un wrap the harness, and get rid of all the aftermarket stuff attached. Then I would test each color wire individually with a multimeter set to ohms, and then repair each wire that had a problem. Once the wiring was fixed to factory specs, then I would add back the extra circuits you need or require, the proper way. For me, redoing a whole new Power distribution system would be a lot harder for me to do than repairing and fixing the old one. But each person is different. P.S. Whatever way you chose, I would not recommend replacing just one circuit at a time, knowing there are other issues with other circuits. One section of harness at a time, yes, but one circuit at a time could cause unforeseen issues, and some that could be dangerous. If you have a bunch of new circuits with inline fuses, I suggest installing an auxillary fuse panel. Which I recently did to mine and documented here: https://forum.garysgaragemahal.com/Electrical-distribution-and-lighting-upgrades-tp127722p129831.html $17 on eBay, included some fuses too. Now in my case, I had already upgraded to a PMGR starter which allowed me to move non-starter battery power distribution from the starter relay to the new fuse panel. If using the moving pole starter (and no plans to upgrade to PMGR), one could replicate this by moving everything but the battery feed to the starter relay; one would branch from the relay to the fuse panel, and everything else to the panel. Is it as fancy as some of the other builds around here? No. But it works and wasn't too much extra wiring. Link to comment Share on other sites More sharing options...
BabeTheBlueOx Posted January 17, 2023 Author Share Posted January 17, 2023 That's an interesting question. And you will probably get several very different answers. In fact, you might get more than one answer from me. First, what you linked to is what I have planned to do for Dad's truck, but haven't done it yet. However, I've done that an more on Big Blue. I used an identical power distribution box on Big Blue's passenger's side and put the circuits shown in it. However, it turned out that the Bosch cube relay is not strong enough to pull in the PMGR starter that I have and started giving problems. So I rewired and went back to the standard fender-mounted relay for the starter. But I kept the fuses replacing the fuse links. Later I converted to EFI and put a similar power distribution box on the driver's side of Big Blue, and it has things like the fuel pump relay, EEC relay, etc in it. And now to your question. I guess it depends on where the problems are with your wiring. If the issues are downstream of the fuse box then I don't think changing would help. So, where are the problems? Great advice all around so far, thank you all so much. What I would do if this was my project. I would get a reputable wiring diagram for your truck, remove the problem harnesses completely from the vehicle, un wrap the harness, and get rid of all the aftermarket stuff attached. I'm very comfortable with electronics and wiring. Your "remove one wiring harness at a time" strikes a note. That would be a very controlled approach to getting everything back to standard wiring and quality. Can you point to any resources that go through wiring harness removal? I'm guessing it's probably pick a starting point, then disconnect and follow until you get an entire harness off, but I've been WAY wrong before. And now to your question. I guess it depends on where the problems are with your wiring. If the issues are downstream of the fuse box then I don't think changing would help. So, where are the problems? The problems have all been downstream so far with wire breaks and bad grounds. But the fuse block under the dash has cut wires hanging off it, wires pressed into fuses from the top, wires spliced together with electrical tape.. everything you can imagine. So I'm kind of looking at this as a "fix it before it breaks" project so I can pick convenient times to have the truck out of service. Link to comment Share on other sites More sharing options...
81-F150-Explorer Posted January 17, 2023 Share Posted January 17, 2023 Great advice all around so far, thank you all so much. What I would do if this was my project. I would get a reputable wiring diagram for your truck, remove the problem harnesses completely from the vehicle, un wrap the harness, and get rid of all the aftermarket stuff attached. I'm very comfortable with electronics and wiring. Your "remove one wiring harness at a time" strikes a note. That would be a very controlled approach to getting everything back to standard wiring and quality. Can you point to any resources that go through wiring harness removal? I'm guessing it's probably pick a starting point, then disconnect and follow until you get an entire harness off, but I've been WAY wrong before. No that is pretty much it. Each section has it's own harness, like the Alternator Harness, left and right engine bay harness, frame-rail harness, taillight harness, and things like that. They all unplug in full sections for easier service. Even the main harness under the dash is removable, just time consuming etc. Removing the dash pad can give good access, after the A/C ducts are removed for example, if even equipped with A/C. So pick the most screwed up harness, and go from there, and work forwards/backwards etc. As for resources, this site is a really good one for help. Look at the top under documentation, then electrical for some good information. If you have questions, ask here and one of us will be able to help. Pictures also help us understand what is going on if you have a problem. Link to comment Share on other sites More sharing options...
BabeTheBlueOx Posted January 26, 2023 Author Share Posted January 26, 2023 Great advice all around so far, thank you all so much. What I would do if this was my project. I would get a reputable wiring diagram for your truck, remove the problem harnesses completely from the vehicle, un wrap the harness, and get rid of all the aftermarket stuff attached. I'm very comfortable with electronics and wiring. Your "remove one wiring harness at a time" strikes a note. That would be a very controlled approach to getting everything back to standard wiring and quality. Can you point to any resources that go through wiring harness removal? I'm guessing it's probably pick a starting point, then disconnect and follow until you get an entire harness off, but I've been WAY wrong before. No that is pretty much it. Each section has it's own harness, like the Alternator Harness, left and right engine bay harness, frame-rail harness, taillight harness, and things like that. They all unplug in full sections for easier service. Even the main harness under the dash is removable, just time consuming etc. Removing the dash pad can give good access, after the A/C ducts are removed for example, if even equipped with A/C. So pick the most screwed up harness, and go from there, and work forwards/backwards etc. As for resources, this site is a really good one for help. Look at the top under documentation, then electrical for some good information. If you have questions, ask here and one of us will be able to help. Pictures also help us understand what is going on if you have a problem. One more question (until the next one). Do you have a recommended approach/parts to replace the connectors between harnesses if they need replacement? Link to comment Share on other sites More sharing options...
BabeTheBlueOx Posted January 28, 2023 Author Share Posted January 28, 2023 One more question (until the next one). Do you have a recommended approach/parts to replace the connectors between harnesses if they need replacement? I answered my own question after some for searching: https://www.garysgaragemahal.com/#nabble-td23210 Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 28, 2023 Share Posted January 28, 2023 I answered my own question after some for searching: https://www.garysgaragemahal.com/#nabble-td23210 Sorry that I missed your question, but you found a good thread on that subject. Link to comment Share on other sites More sharing options...
81-F150-Explorer Posted January 28, 2023 Share Posted January 28, 2023 Sorry that I missed your question, but you found a good thread on that subject. I'm sorry as well. Hope things are going well. Yes, used harnesses are a great place to look for connectors. Ford cars from the same era can produce connectors that you can use as well. Link to comment Share on other sites More sharing options...
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