Park Tail fuse melting box?

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svwilbur
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Re: Park Tail fuse melting box?

Post by svwilbur »

Ok thanks all. I need some more guidance. I looked at the back on the fuse box in in the roadster and it is a little different than the one I wanted to use. I have one box like the one on the car and 3 that are different.

The one that is like the one on the car has less brass bars on it. I attached a copy of the two styles I have.
It appears that the one is just a beefed up version of the other. Following the brass connections they appear to do the same thing.
One goes down to the bottom and riveted through to other sides fuse holder. The other crosses-over above the connector and then down and back under itself and is still riveted to the fuse connection on the other side.
The one on the car matches the one with a single brass bar, less beefy type, no crossover. I am not sure if it makes a difference or not???????

Can I use any of them or is there something different about how it is used?

Also looking at the wiring on the back on them they all seem to be using the same color coding on the wires and to the connection blocks.
So that seems ok. But they all do NOT match the color coding in the schematic here: http://www.311s.org/PDFs/1969-70%20Dats ... 20rev9.pdf

They seem to match on the WR side but are all different on the other side of the schematic. Even the fuse amounts are different, like flipped upside down?
I heard that there are really about 10 different schematics so maybe this one does not match my car but it does mention 1970 on the bottom for the door buzzer.

But on my roadster I have a WR wire that connects separately with a screw on the right lower side viewed from the front, which I take is standard as I see it on the schematic going to the Alternator and Ammeter. It is also on one of my boxes as a cut off wire. This supplied power to that whole side.

But on my roadsters fuse box I also have a GW wire on the opposite screw at the bottom. I can not find that on the schematic. It does occur on one of my spare boxes, the same one with the WR cutoff wire and this GW is also cut I guess when ever this was taken off a parts car they unplugged the connections and just cut the other wires off. The GW just supply's power to the first connection.


Here are some comparison pictures of the two types of boxes. The one with the WR and GW wires coming off the bottom screws is like the one in the roadster.

On the first/top photo looking at the back all the input power comes from the WR wire at the bottom. The brass in the middle just makes a "bridge" to power the other center connections. But why does it look different than the one on the right which uses crossover brass pieces?
The part that bridges the other connectors to the right is a little higher on the right box as well. same function just different.

The righthand side of the fuse box (as viewed from the back) appears to be powered from 3 different sources, GW on bottom connection, BLKW on the second connection up and BW on the top two connections that are bridged together.

So my questions are:
1) what is the GW wire for on the bottom left screw as viewed from the front, I assume it provides power from somewhere?? The schematic does not match up for that side.
2) what is reason for the additional brass crossover bars to make the connection by going over the connector and then down around ??
3) does that additional brass crossover bar do anything better, more distance traveled, heat dispersion?

4) can I uses these boxes interchangeably to replace my roadsters box which does not have the additional Brass crossover bar?
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Re: Park Tail fuse melting box?

Post by RBMann »

I know, not a roadster. Here is what a loose connection in a house thermostat can do.

Image

Image
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svwilbur
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Re: Park Tail fuse melting box?

Post by svwilbur »

I am still looking for a answers to my questions above;
So my questions are:

1) what is the GW wire for on the bottom left screw as viewed from the front, I assume it provides power from somewhere?? The schematic does not match up for that side.
2) what is reason for the additional brass crossover bars to make the connection by going over the connector and then down around ??
3) does that additional brass crossover bar do anything better, more distance traveled, heat dispersion?

4) can I use these boxes interchangeably to replace my roadsters box which does not have the additional Brass crossover bar?
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msampsel
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Re: Park Tail fuse melting box?

Post by msampsel »

The boxes look to have the same function to me.

Maybe the GW wire on your box pertains the schematic comment (GR on original, GW on wiring harness?).
This is a question for Curtis.
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Re: Park Tail fuse melting box?

Post by Curtis »

msampsel wrote:The boxes look to have the same function to me.

Maybe the GW wire on your box pertains the schematic comment (GR on original, GW on wiring harness?).
This is a question for Curtis.
Okay, sure, drag me in to this.

Loose connection, rivet, etc. equals burning.

I haven't carefully studied the pictures of the boxes yet but there seems to be a mix of boxes. From what I have seen so far based on the schematic notes and looking at the couple boxes I have on hand Datsun as usual changed them during the two years 69-70. Add to that the same box is used on the 510 and can be made to work on the roadster.
The wires coming off the box are not in all cases the same color as the wire it hooks to in the harness. This drove me nuts at first when I started looking at one of these.

Green wire with white stripe, you have a couple of those on the box. The one is a direct feed from the starter harness and feeds the horn fuse and brake lights. the wire coming out of the box to do this feed is greed/red and changes to green/white at the plug.

The other green/white wire feeds the park lights to the switch.

I would be tempted to adapt this box. Pricey but modern. http://www.thezstore.com/page/TZS/CTGY/classic10a03
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Re: Park Tail fuse melting box?

Post by svwilbur »

I got the old fuse box out. It had the melted area around the outgoing fuse holder, melted over to the other connectors on each side. but that rivet connection was tight or seems tight. connector was no longer connected to box, it was free floating, could hit the other connectors beside it I suppose. But the rivet did not seem loose now. Maybe it welded itself back together? It was still working. Remember I am not digging into this because something did not work. I am digging into it because I was checking the fuse box to see what fuses it used to get some replacements just in case....

The wire is melted back from the heat and had corroded around that upper wire connection where it is usually insulated by the plastic wire covering. But none of the other wires had corroded so I think this was from it heating up. But why was it heating up? Maybe other bad connections on the circuit? or maybe it was loose and welded itself back together?


Another question about the fuses Assuming my cover is correct and the fuses in my 2 other boxes are correct they should be all either 10 or 20 amp fuses. I had some deviations. in my box on the roadster

It had a 25amp on the bottom right which should be 20amp
The one with the melted area was a LITTELFUSE USA SFE 20A which from what I can tell should blow within 2 minutes if over AMPed.

I see some of my fuses are 10A Life Japan and 20 AMP Life Japan ( I assume original)

Others I had and in what position :
Littel Fuse USA SFE 20A( in a rated 20 AMP socket, 1st on top on LEFT)
250V 10A BUSS F03A (in a rated 10 AMP socket, 2nd from top on Left)
BUSS AGC 15 (in a rated 20 AMP socket, 3rd from Top on Left)
311 3AG 25 A 32V (in a 20 AMP rated, bottom Left socket)

10 A Life Japan (in a 10 AMP rated socket, Top Right) the end cap was loose on glass
10 A Life Japan (in a 10 AMP rated socket, 2nd from Top on Right)
LITTELFUSE USA SFE 20A ( in a 20 AMP rated socket, 3rd from Top on Right) This one had the melting issue
311 3AG 25 AMP 32V (in a rated 20 AMP socket, lowest on Right)

My other used boxes that still had fuses had 20 and 10 amp fuses in correct places.
Except one had 250V 10A BUSS F03A in (2) 20 AMP sockets (3rd and 4th from Top on Right)
And a 10AP life Japan in another 20 AMP socket( 2nd from bottom on Left)

Apparently according to the web AGC 20 and SFE 20 can be interchanged.

I know that some fuses are SLOW BLOW and others are FAST Acting.
Which type should we be using in roadsters?
What are the correct fuse sizes and types and brands and numbers that work properly?




I also found this on the web talking about fuses:

"SFE fuses are 'automotive', rated only to interrupt 32 volts. The length depends on their current rating, ranging from 5/8" for a SFE-4, to 1-7/16" for a SFE-30. AGC fuses are 'general purpose', they are always 1/4" by 1-1/4", available in 250V ratings to 10 amps, & 32V ratings to 30 amps.

An AGC-20 is the same length, & pretty much interchanges with an SFE-20. Both types are "fast acting", but according to my Buss charts, the SFE is a little faster. An AGC-20 is rated to carry 27 amps for up to 60 minutes, while an SFE-20 will blow in under 2 minutes. However, the 60 minutes is given as a maximum, while the 2 minutes is apparently typical, so that may not be an accurate comparison.

SFE Glass fuses are designed to specifications set by the Society of Fuse Engineers. All are 1/4 inch in diameter, but vary in length according to the ampere rating to ensure accurate fuse replacement. Both AG and SFE fuses were designed into North American vehicles prior to 1981. Glass fuses are also used for auto accessory applications.

SFE = Society of Fuse Engineers
AGC = Automotive Glass Cartridge"
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Re: Park Tail fuse melting box?

Post by fj20spl311 »

The melting IS from a bad connection and not a overload. The rivet was my first choice [from experience], but any loose connection is possible. I have also seen the clip be loose and arc. It really doesn't matter.....LOL
Install the new old box and go forward.
If it was from too large a fuse and overload....this wire would be melted though out the wiring loom [very bad].

Stacey...you are over thinking it.
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Re: Park Tail fuse melting box?

Post by svwilbur »

yup ok but...

I know that some fuses are SLOW BLOW and others are FAST Acting.
Which type should we be using in roadsters?
What are the correct fuse sizes and types and brands and numbers that work properly?
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Re: Park Tail fuse melting box?

Post by fj20spl311 »

"An AGC-20 is the same length, & pretty much interchanges with an SFE-20"
Any fast fuse....looks like 3-10A and 5-20A
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Re: Park Tail fuse melting box?

Post by msampsel »

O'Reilly's has the AGC variety pac in my neighborhood.
Fast acting only. Never used a slow blow on anything other than a radio.

A lose connection works like an arc welder. Which is apparent from the melting.
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Re: Park Tail fuse melting box?

Post by Curtis »

Fuses are cheap, wiring is not. I would never use a slow blow.
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Re: Park Tail fuse melting box?

Post by Jdflyer »

Agreed you do not want a slow blow. If something is wrong in a circuit you want to stop the flow of electricity before it does any damage
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Re: Park Tail fuse melting box?

Post by redroadster »

Speaking of arcing, anyone else having trouble with the new style flouresant lite bulbs arcing at the base 120v a/c ...I am ,no trouble with the old style I tighten as much as possible too
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Re: Park Tail fuse melting box?

Post by fj20spl311 »

redroadster wrote:Speaking of arcing, anyone else having trouble with the new style flouresant lite bulbs arcing at the base 120v a/c ...I am ,no trouble with the old style I tighten as much as possible too
I am replacing my CF with LED as they burn out. I have not tried the "SHOP LIGHT" LEDs yet, but soon.
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Re: Park Tail fuse melting box?

Post by svwilbur »

I have replaced almost all my house CFL with LED. I have not changed the CFL I have in enclosed hall and bedroom lights as the LED package says not to use them in enclosed fixtures because they will get too hot or where directly exposed to water. I do use them in my covered outdoor lights, ipen bittom. they work really great at the 60 watt daylight type equivalent. brighter than the CFL I had out there and reduced my electric bill enough that I burn them more now. they are like 9 watt each. I used to have (7) 100 watt incandescent, use (7) 9 watt LED. 700 versus 63 total. 11 times less watts but just about as bright

I do have a 4 double foot shoplite LED I got from costco cheap. it works well. just does not have a switch so I forget to turn it on. would be good if you have a switch outlet. thanks for reminding me it is there!
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