Fuse box solution

Ove · 10-12-2002, 03:12 AM

I've had many electrical problems with my 911 and almost every single one of them has been traced back to the fuse box.

- The old round style fuses seem to corrode easily and have less contact area with the fuse holder than the new style fuses do.
- The fuse holder itself corrodes as well, where it holds the fuses and where the wires are attatched.
- The wires corrode in the ends where they meet the fuseholder.

My solution is to fabricate a new fusebox which accepts fuseholders for new style fuses. I wanted to retain the factory look, therefore I am keeping the round (and expensive) relays.
Will probably paint it black too.
Not finished yet, but you get the idea from looking at the picture.

autobonrun · autobonrun's Garage

This looks like an excellent project. Mine needs the same. I'll be curious how long it takes you to make the change. Did you just fabricate the housing because you have the skill or do they not sell it?

In my case, a few of the wires show burned insulation at the top of the fuses, not just corrosion. I've reinsulated them but it makes me wonder what caused the wire to overheat if the fuses are sized correctly.

Also, did you consider a circuit breaker box similar to those used on boats when you decided to change? I've heard some have done this.

79SC

Doug Zielke · 10-12-2002, 07:37 AM

Ove, this looks like the start of a very good project. Nice work!

The ancient fuses and panels have long been a source of vexation for this owner. I have often thought about doing exactly what you *are* doing.

I'm glad you elected to use *fuses* instead of circuit breakers, and retaining the OEM look is also a good idea.
Please keep the Board posted as to your progress.
Keep notes as to the details. If your conversion is solid, this is a marketable item.

GeorgeK · 10-12-2002, 08:34 AM

That is great!
I did the same afew years ago, because the panel was in bad shape. I took the opportunity to clean all the fuses/holders/cables at the same time. Then I had some material left and I built a Brake bottle support, a smuggler's bok lid, a rear cover for the ventilation.
I should have thought about putting the new type fuses too.

georgeK

RoninLB · 10-12-2002, 01:41 PM

I added an 8 pin CB marine panel for added stuff..power seats/high power headlights/etc..mucho better than in line fuses IMHO..it fits on floor at front/left under battery ground/chassis bolt..a full aircraft CB panel will happen down the road to replace the stock/lousy/PIA fuse panel..the 8 CB panel is around $100..I suggest marine grade CB panel and wires....I like it as bullet proff as possible/screw stock......................Ron

makaio · 10-12-2002, 02:03 PM

Very cool project. Can't wait to see how it goes.

And George, your front trunk is beautiful!

pwd72s · 10-12-2002, 04:41 PM

Quote:

Originally posted by Doug Zielke
Ove, this looks like the start of a very good project. Nice work!

The ancient fuses and panels have long been a source of vexation for this owner. I have often thought about doing exactly what you *are* doing.

I'm glad you elected to use *fuses* instead of circuit breakers, and retaining the OEM look is also a good idea.
Please keep the Board posted as to your progress.
Keep notes as to the details. If your conversion is solid, this is a marketable item.

Doug, if memory serves, you are an electrician by trade. Want to elaborate on why you prefer fuses over circuit breakers, especially marine or aircraft grade?

Ove · 08:52 AM

Thanks,
I appreciate your replies and suggestions.

I cut the box myself from a piece of 1.5mm (?) aluminium already bent 90 degrees. I used a heavy duty hand saw (electric) for the cutting, except for the round holes. The round holes were done using a hole saw mounted on stationary drill. The aluminium was free, the fuse holders were $22 (all 4). Round relays with holders are of course expensive...

I don't like the circut breakers because I feel you could fry the electrics while resetting them. If they pop because there is a short somewhere and you push them back to the on-position they are unable to pop out again while you hold them. Until you release them current flows and could melt some other electric part. This is what I FEEL, not what I know. I believe they are constructed in a way that prevents this from happening?

I made a few extra round holes compared to the original part, 4 of them will be used to accommodate headlight relays (2 low beam and 2 high beam relays).

The fuses will be in the stock location counting from left to right.
I have seen this type fuses with small light bulbs in them. The lights go on when the fuse goes out. Does anyone know who sells them?

The wires to the fuseholders will be soldered to the golden connectors (from a car stereo shop) where connector size permits, and will be covered with heat schrink tubing to keep moisture out.

I'm afraid it will take some time before I can show you the finished work, but I promise you will see it when I get done with it. It is one of my many winter projects along with detailing and painting the front trunk. Thanks to George, now I know what my front trunk should look like!

Any other ideas? Please let me know.

Seven-Seven · Seven-Seven's Garage

Ove--

Here's an online source for the lighted blade fuses you're looking for:

http://www.jcwhitney.com/product.jhtml?CATID=373041&BQ=jcw2

Siena911 · 10-14-2002, 12:52 PM

Very nice work,

I am always astounded at all the good ideas that come from this forum. Keep us posted, I am keen to see what the outcome is like

Cheers Jakes

btw, nice link to those ligted fuses, I have never heard of those before.

Ove · 10-15-2002, 01:44 AM

Thanks again,

Great link to the lightes fuses, Seven-Seven.
Here is another pic.

Ove · 08:51 AM

And this is the mess I have now.
Notice that on the new box the wires will be hidden on the back of the panel, making things look more tidy. I am planning on making a fiberglass cover (painted black) because the old one will not cover the added fuses and relays.

TurboRuf · 10-15-2002, 06:21 AM

911777,

This is a great thread, I thought of doing this myself.

How do the wire's attach on the backside of the new fuse blocks? Where did you find them?

Ove · 10-15-2002, 08:49 AM

autobonrun,
I think the reason why your wire insulation is burned is that corrosion has restricted the current flow in the wires or the fuseblock. The area becomes a resistor and heats up when electricity is turned on in the circut, causing the insulation to melt/burn.

TurboRuf,
The wires attach on the side of the fuseblocks using regular auto connectors. You can see one connector mounted in the first picture. I will be using gold plated connectors to further improve corrotion resistance. I bought the fuseblocks here:

http://www.biltema.no/
(left menu: "bil", "biltilbehor", center of screen: "BIL EL", "sikringer", scroll down and click on the pic.)
A set of 4 is $22. (not $15 as stated in my previous post).

I could get them for you, but you should check with Wayne first to see if he sells something similar.