5 Amp fuse. Where do I get one?

05-09-2001, 05:20 PM

I cleaned up my fuse box, and I broke one of the yellow 5 Amp fuses in the process. I can't seem to find them at any auto parts places. Even Pelican and other vendors do not offer the yellow 5 Amp fuse. Where do I find these things?

Help!!!

Paul
81 911SC

05-09-2001, 06:45 PM

Did ya try your local Porsche "stealership?" ahem I mean "retailer"?

Believe it or not, for certain little nuisance items like this, their prices are about the same as everybody else's, and they often have the stuff in stock...

05-09-2001, 07:48 PM

Couldn't you just break a 10 amp fuse in half, and use that? Then you'd have a spare!

Sorry, a weak attempt at humour there. Seriously, try Radio Shack.

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Clay McGuill '66 912, '97 Jeep Cherokee www.geocities.com/the912guy

05-09-2001, 07:58 PM

Thanks guys, I did try the local Porsche dealer, and they said "no we don't have those, just use a 8 Amp." I have yet to try Radio Shack, I will try them tomarrow.

Thanks,

Paul
81 911SC

05-10-2001, 04:43 AM

I went through the same search a couple of years back. No one nearby seemed to stock 5 amp fuses. Then, on a little driving excursion, I stopped into a NAPA store to buy some oil. Lo and behold they had all types of german fuses (although they were the glass type and not the OEM Porsche). I bought every 5 amp fuse they had!
I guess it pays to just drive around and look in every car parts store.

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Dan Tolley
1987 911 Coupe
http://www.cheaterswayside.com/911/gallery.asp?sort=0&userid=294

05-10-2001, 05:58 AM

Drop into Discount Auto Parts - I think they call them European fuses.

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Allan Broadribb
'70-911E, 2.2l with Webers
http://www.cheaterswayside.com/uploads/Mvc-002s355.jpg

05-10-2001, 02:30 PM

Thanks Dan, I stopped at a NAPA today, and BINGO they had them. Here is the NAPA part # if you need some (782-1102). They had 5 of the original yellow type, and then I ordered 10 more that I believe are the glass type (the guy at NAPA said that they are the same thing, just in a different style). All the 8, 16, and 25 AMP fuses on the shelf were the glass style.

Paul
81 911SC

oly · oly's Garage

Our local NAPA only had the clear glass tube type. Pelican still does not have them. So I got them from Sunset Imports, P/N 900-173-006-90, for $0.43 each. They are yellow instead of the pink (orginally red maybe?) ones that are in the car.

Early_S_Man · 12-13-2006, 06:57 PM

Littlefuse or Buss GBC 5 fuses are either the ceramic style as the OEM German fuses, or they can be glass with soldered conical ends. See pics, here:

Source for 5amp fuse?

Wil Ferch · 12-14-2006, 06:20 AM

Quote......"I did try the local Porsche dealer, and they said "no we don't have those, just use a 8 Amp." ..."

Idiots !!!! .....8 amp is 60% ( ! ) higher than spec value....and we wonder why we have electrical problems when Porsche's designs are poor ( not enough fuses), and when we do use fuses....they're 60% stouter than spec....

Stupid Porsche dealer idiots !!! ...........

- Wil

Jim Sims · 12-14-2006, 06:37 AM

Actually in terms of power or heat generated in the wires when it finally blows an 8 amp fuse is 156% higher than a 5 amp fuse.

Zeke · 12-14-2006, 06:38 AM

What is the mn wire size to be protected by a 5 amp and what is the min wire used in a 911?

304065 · 12-14-2006, 07:05 AM

Ahh, Jim! I-squared R, right?

5 amps squared = 25
8 amps squared = 64

(64-25)/25 = 156%!

Wil Ferch · 12-14-2006, 07:47 AM

The point still remains that there is a "reason" for a 5a rated fuse to exist... and to have an official-sounding recommendation from a Porsche facility to suggest use of a 8A instead...is insane and borders on the criminal.

Take it from someone who had a $3000 wire-harness fire due to similar reasons on actions done by the PO. I guess I'm "funny" like that ....

- Wil

304065 · 12-14-2006, 08:03 AM

Yep, Paul, there's your answer. . . and it only took five years, seven months and three days for the Board to reply!

Paul?

Paul?

Wil, let's hear about this harness fire of yours!

Wil Ferch · 09:47 AM

It's a rather long involved story.... cliffs note version follows:

Some kind of relay behind the dashboard failed internally ( random fluke ?)...where an internal piece broke off and landed on the "other" ...control side... of the relay circuit. The control-side of the circuit was now energized from the "power side"....and the control side was "protected" by an improper ( too-high amp rating) fuse installed that caused that circuit ( normally 5A, interior lighting) to fry, smoke, and melt. Car was smoking in the cockpit, and as I stopped the car and turned the key off and out....the car kept on running and smoke continued to pour out of every vent and thru every orifice in the cockpit. Quick run to the engine compartment and pulling wires got the car to stop running....followed by a quick sit-down to get the adrenaline out of your knees.

Fix.....completely new wiring harness ( "sorry...none in the USA...hafta ship from Germany"). Work involved removing all gauges, gas tank, steering, rewiring the front-end of the car and under the dash, cruise control wiring, etc.....

Upside?....the people doing the work were anal and fastidious such that point-to-point wiring as well as clipping / clamping was done totally to factory specs. Today, there is no hint of having had any problem, and I now have newer wires ( no corrosion, still subtle insulation)...and may have come out of this ordeal even better than OEM... by being newer.

But still $3000 for parts / labor / downtime and research to do "right"....

- Wil

Jim Sims · 12-14-2006, 09:46 AM

It's times like this that I really appreciate Mr. James Placek's high school physics class. If you get out of high school not knowing P=I^2R you've been cheated.

Jim Sims · 12-14-2006, 11:52 AM

"What is the min wire size to be protected by a 5 amp and what is the min wire used in a 911?"

Ampere capacity depends on wire insulation type, bundling and duty cycle (how long the circuit will be on) but here are some conservative values for copper metric wire based on 80 deg C rated insulation and wiring bundles containing 16 to 30 wires.

.6 mm^2 wire: 5.8 amps
1 mm^2 wire: 9.65 amps
1.5 mm^2 wire: 14.5 amps
2.5 mm^2 wire: 24.1 amps
6.0 mm^2 wire: 57.8 amps

mm^2 means area cross-section in square millimeters.
I recall seeing all the above metric wire sizes in a 911 wiring diagram.

This is based on about 200 circ mils of copper per amp.

Some very conservative wiring codes require 700 circ mils of copper per amp.

stallturn · 12-14-2006, 12:49 PM

Quote:

Originally posted by Blackdimonds
I cleaned up my fuse box, and I broke one of the yellow 5 Amp fuses in the process. I can't seem to find them at any auto parts places. Even Pelican and other vendors do not offer the yellow 5 Amp fuse. Where do I find these things?

Help!!!

Paul
81 911SC

Hi Paul

Try eBay, just ordered 50 of them at various values(5 included) here in the UK cost around $12.
hope this helps.

wallstreet · 08:38 PM

There is a pack of glass fuses on ebay. Ciurrently. 8/16/25 amp and ask for 5's. GLASS TYPE for less corrosion

Quote:

Originally Posted by JDaniel

I went through the same search a couple of years back. No one nearby seemed to stock 5 amp fuses. Then, on a little driving excursion, I stopped into a NAPA store to buy some oil. Lo and behold they had all types of german fuses (although they were the glass type and not the OEM Porsche). I bought every 5 amp fuse they had!
I guess it pays to just drive around and look in every car parts store.

------------------
Dan Tolley
1987 911 Coupe
cheaterswayside.com