Some more 521 Electrical issues

[521Symmonds]

Well lately I've been having issues with most of my accessories in my 71 521. The electrical has been randomly modified over the years with a few add ons like:

105amp?(unsure did swap about 3 years ago) gm alt.

dual (unknow amp) electrical fans(wired to battery, runs on toggle switch, and yes fuse protected)

completely new stereo(wired to battery)

Lots of small rewiring to get me or my dad home over the last few years.

At least enough rewiring has been done to make the wiring diagram a large headache to use to trace anything thats not my lights or igniton.

Anyways, today i was happily driving to work, had the fans running, stereo on, and ipod radio thingly for tunes. it was running fine until i turned on my markers and hit a large bump. Stereo goes out, markers die, I almost got ran over by a lifted silverado so i can assume my brake lights died also, and cooling fans run about 1/4 of what they usually do. So i go ahead and turn everything off but the fans, and those get back to about 3/4 capacity. I get to work, shut off the truck and pull out my multimeter. No blown fuses, no burnt wiring, and got full 13v's over my fuse box, give or take 1/2 a volt. I go to key on and everything drops to 8-9 volts. My fuse box is soaking right now in some vinigar. I also forgot which systems are hot on key on and run. The problem isnt in my ignition circut as far as i can tell. Has anyone had a similar issue recently? I can also post pics if need be, just tell me what you need to see.

[flatcat19]

Rip it out. Start over.

You can find quality full re-wire kits on eBay.

Trying to band-aid your electrical system now will just have you back here asking the same question in weeks.

[DanielC]

Start with this. Clean your battery terminals. If the connection is bad, drawing a fair amount of current through it can cause a voltage drop. Also if the battery is slightly discharged, when the alternator tries to put electricity back into the battery, this same voltage drop makes the alternator think the battery is charged, when it is not.

[521Symmonds]

Flat: I'd love to rewire my truck, but I got to drive it to work tomorrow :blink:

 

Dan: terminals are clean, battery is on a charger atm due to leaving the key on on accident. Thankfully when I turn the key off, battery goes to 12 volts by itself, but I'm topping off for security. I'm not sure the alternator is thinking its charged when I can't get the damn thing to turn over because I don't have enough power to get the starter motor to engage, let alone get it spinning at all.

To this day I'm still trying to figure out how my dad wired up the alternator, even he doesnt know what he did, it was mostly trial and error and bursting batteries.

 

The only way I was able to get the truck started was using a jumper pack to get to 12 volts on the battery with the key on and then running a wire from my battery to my starter by hand. After it started the alternator charged fine but I can tell something was still drawing enough of a load to make me only able to run the cooling fans, lights worked, they were just extremely dim and my turning signals were cycling very slow.

 

I've had this issue quite a few times, and I'm starting to run out of things to fix or rewire.

[wayno]

I agree with DanielC, it seems like it has something to do with the battery, the battery connections or the cables themselves. All 12 volt batterys show 12 volts, that doesn't mean they are charged or will turn anything over.

[521Symmonds]

Yeah I'm going to get that battery checked out soon. Popped the fuse box back in, replaced a few connections and a lot of contact cleaner and it runs again with no issues. This datsun just needs a lot of bandaids til its not my daily driver. The fun will begin after that.

[banzai510(hainz)]

Do not rewire!!!!!!Find each proplem, Most times its just corriosion.

[fryenretards]

sounds like your alternator might not be putting out enough voltage maybe? how many volts is it putting out when ur just at an idle? should be upwards of 14ish 13.8 is low 13.6 very low but driveable i bet ur around there in which case bad alternator