My 70 521 fuse box

[bilzbobaggins]

Ive looked through the wiring diagrams on olddatsuns.com....ones for the j13 521 and ones in the 521 repair manuel at the end....they dont match mine...they are close tho

 

mines got more fuses....my 8 to books 6.....search has shown me pics of others that are six....

 

 

 

the right 4 fuses are always hot, the 4 to the left when ignition is keyed on...anyone else have one like this??

 

has "custom wiring" to it...some PO sprayed under the hood to include the harness...just trying to work it out..

 

cant wait to make her my dd

 

thanks forks

 

jeff

[DanielC]

That is not stock. Here is a picture of my 521 fuse box, also not stock.

Four of the fuses are always hot, and two of the fuses are switched by ignition. I Just took a quick glance at a wiring diagram I have for the 521, and one of the switched fuses has two wires coming from it.

 

Check out this thread also:

http://community.ratsun.net/index.php?showtopic=2534

[bilzbobaggins]

thanks man....your fuse box was one of the ones i found when i did a search earlier lol...well....now i know...im replacing the thing with the atc ones...just gotta figure it all out now..wonder why someone added the two circuts??

 

thanks again

 

jeff

[DanielC]

Some of the stock fuses did double duty. When you go back to my older post, it tells what every fuse did. I think it was complete, but it may not be. I am not responsible for and additions that were done to your truck by the dreaded "previous owner".

 

One area on your truck that I would suggest adding to is to make sure everything is grounded. The battery negative connects to the engine, by the fuel pump, and there is an additional ground wire that goes down to the alternator case. There should also be a ground wire that connects the alternator frame to a lug that goes under the voltage regulator mounting bolt. There is also a ground wire from the voltage regulator mounting to the headlights.

 

The engine needs to be grounded to the frame.

 

The cab needs to be grounded to the frame. If you do not do this, and for some reason the existing ground goes away, the cab will try to ground through the throttle and choke cables, melting the outer casing, and destroying them

 

The bed of the truck needs to be grounded to the frame. You might have to run a separate ground wire from the taillight frames to the frame of the truck.

 

A lot of these extra grounds I am suggesting were not on the truck originally, the parts used to just ground through bolts, but have the potential for going bad after forty years. Adding them now can save you a lot of grief later.

[datzenmike]

 

The cab needs to be grounded to the frame. If you do not do this, and for some reason the existing ground goes away, the cab will try to ground through the throttle and choke cables, melting the outer casing, and destroying them

 

 

Absolutely true!!! Back in the '70 I drove around just like you young guys with not even a bungee cord holding the battery in. Battery flipped over and the + touched the body, power had to travel down the throttle cable to ground on the engine. Got glowing hot before I could stop and fix. Plastic hardened around cable and stuck at idle. Set it on fast idle cam and drove 15 miles home, 2 in the morning, drunk, stopped by police. He must have liked Datsuns, let me go on my way. I don't do that anymore.

[datsunaholic]

Wow, that's one epic kludge fusebox. Including the tinfoil "fuse". Good way to melt the rest of the wiring harness.