Laecaon Posted January 9, 2012 Report Share Posted January 9, 2012 To make a short story shorter, the E and A terminals got grounded on my friends 521 with battery in, but no voltage regulator installed. It got shorted for a few seconds, could here the positive starter post crackling a bit. So now the fun part. Nothing works, well sorta. You randomly will get oil/ign lights on dash. Randomly all lights and circuits works, but usually not. Starter will not bump, and if you do so with the lights on it will kill all circuits. Brake lights dont work either. If you do manage to get the oil/ign light on with the key touching any switch will turn everything off. That said, Battery has fine voltage, You get 12V on the 4 battery power fuses. All fuses have been replaced for funsies. I dont see any fusible links on the car. Quote Link to comment
Guest kamakazi620 Posted January 9, 2012 Report Share Posted January 9, 2012 To make a short story shorter, the E and A terminals got grounded on my friends 521 with battery in, but no voltage regulator installed. It got shorted for a few seconds, could here the positive starter post crackling a bit. So now the fun part. Nothing works, well sorta. You randomly will get oil/ign lights on dash. Randomly all lights and circuits works, but usually not. Starter will not bump, and if you do so with the lights on it will kill all circuits. Brake lights dont work either. If you do manage to get the oil/ign light on with the key touching any switch will turn everything off. That said, Battery has fine voltage, You get 12V on the 4 battery power fuses. All fuses have been replaced for funsies. I dont see any fusible links on the car. Alternator is fried and dead shorting,had same prob with the 620 but the fuse would blow if you turned key to "on" position If i skipped "on" and went straight to start it started and ran fine but lights and gauges flickered,Try unhooking the alternator and start it up and see if it does the same thing Quote Link to comment
DanielC Posted January 9, 2012 Report Share Posted January 9, 2012 Clean the battery terminals. You need to have the alternator checked. Check the connection to the starter, it should be clean, shiny, not greasy. Check the connection from the starter to the alternator. There is no fuseable link on an 521. Make sure the grounds are good. The battery grounds to the cylinder head, by the fuel pump. There is a thick wire from the battery connection down to the frame of the alternator. From the alternator, there is also a thick wire that goes to one of the screws that hold the voltage regulator to the inner fender. Make sure the engine still grounds to the frame of the truck, the cab, and the bed of the truck still grounds to the frame. Some of these ground connections, that were good when the truck was new, may not be now. You may have to add additional wires to complete the grounds to the body parts. If the ground connection between the engine and cab goes bad, the cab tries to ground through the throttle cable, and that destroys the throttle cable, and may make your throttle stick with the throttle open. Now, the fuse box. It was adequate, when new, for a stock 521. The spring clips get old, and get a layer of corrosion on them. The connection to the fuse starts to go bad, and heats up, and this makes the connection worse. When the spring clips that hold the fuse get hot, they lose their tension, and do even a poorer job of holding the fuse. The push on spade connection on the back of the fuse box can have this problem also. You need to check the voltages after the fuses, with the circuit turned on. There is a bunch of harness connectors by the back side of the glove box. They connect the engine room harness to the cab harness. These could be bad, needing cleaning. That should start to fix some of the electrical problems. Quote Link to comment
Laecaon Posted January 9, 2012 Author Report Share Posted January 9, 2012 Well sometimes you dont get to do things you want to do when it is not your car. This is one of them. I made the suggestion way early on that that positive battery terminal needed to be cleaned ( like probably 15 minutes after he originally shorted the alternator). Well that got regarded as silly. Fast forward to 15 minutes ago and we clean the positive terminal and all is happy. Sigh. I think I will just sip on my tea as he finishes up outside. Quote Link to comment
DanielC Posted January 9, 2012 Report Share Posted January 9, 2012 I clean some rusty Datsun parts using electrolysis. Here is the link. http://community.ratsun.net/topic/3012-electrolytic-rust-removal/page__p__40613__hl__electrolysis__fromsearch__1#entry40613 The parts I want the rust removed from connect to negative. I connect positive to the sacrificial anode. The anode slowly gets eaten up, it is forced to rust, to remove rust from the parts I want to clean. The same thing happens at the positive battery terminal. If any moisture gets on it, it corrodes, and this makes the connection go bad. Quote Link to comment
Laecaon Posted January 9, 2012 Author Report Share Posted January 9, 2012 This corrosion happened because of a short and happened in like 10 seconds. Electrical all works great in the truck. Though 1 day soon (warmer) I plan to re-do his wiring harness, oh the things the PO did. Anyways, now it would appear the alternator is dead, well we tried the voltage regulator bypass test and voltage on the battery stayed at 12.4V. Nothing is simple with this truck. Although that could be our own mistake, but when everything just works fine on my wagon on the first time... Quote Link to comment
Guest kamakazi620 Posted January 9, 2012 Report Share Posted January 9, 2012 This corrosion happened because of a short and happened in like 10 seconds. Electrical all works great in the truck. Though 1 day soon (warmer) I plan to re-do his wiring harness, oh the things the PO did. Anyways, now it would appear the alternator is dead, well we tried the voltage regulator bypass test and voltage on the battery stayed at 12.4V. Nothing is simple with this truck. Although that could be our own mistake, but when everything just works fine on my wagon on the first time... Anytime you Dead short a Datsun the alternator fries!!!! Quote Link to comment
Laecaon Posted January 9, 2012 Author Report Share Posted January 9, 2012 Ok new Napa reman alternator, check. Stripped starter post, check. Why is the starter post made of copper!?!?!?!?!?! It isnt on my wagon... Quote Link to comment
Guest kamakazi620 Posted January 10, 2012 Report Share Posted January 10, 2012 Ok new Napa reman alternator, check. Stripped starter post, check. Why is the starter post made of copper!?!?!?!?!?! It isnt on my wagon... It should be,sure its not painted?? Copper is the best conductor thats cheep The next best conductor is GOLD Quote Link to comment
DanielC Posted January 10, 2012 Report Share Posted January 10, 2012 Actually, copper conducts electricity better than gold. Silver is the best pure metal conductor, then copper, then gold. Gold is the best metal for contacts, because it does not corrode. Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.