Copper ceramic fuses - PeachParts Mercedes-Benz Forum

TnBob · #1 10-21-2013, 10:58 PM

Electrical gremlins can be a true PITA to chase down.

Those issues can be made even more frustrating by a
less than stellar fuse, you know, repaired or aluminum
or just in general 20+ yrs old type fuses.

For those with a 'new to them' MB I heartily encourage
a full fuse change out to the greatly preferred copper
over a ceramic fuse body type.

For those who over time have allowed non coppers to
appear for cost or time or or...your excuses are now moot.

Next of course where to get these gems for less than the
$1 to $2 each many shops want.

Ebay of course. Just got 60 ceramic fuses in with copper
elements for just under $10 delivered. 20 ea of all 3 colors.

Good price and parts were shipped fast by

european-discount-parts
Links go away quickly but he has been selling since 2002 so just
do a seller name search.

As you replace these, one at a time please, take a few extra seconds
with a cleaner like Tarnex to insure the fuse holder is in good contact
shape too.

Mark DiSilvestro · #2 10-22-2013, 09:55 AM

I think many manufacturers, including Mercedes, had been using ceramic with aluminum strips for awhile when the W123s came out. I wouldn't rush to re-do all my fuses this way, but once in awhile, In a pinch, I have transferred the copper or brass strip from a new aftermarket plastic fuse to the original ceramic fuse body.

Happy Motoring, Mark

vstech · #3 10-22-2013, 09:59 AM

yeah... the MB star fuses in my kit all have aluminum elements... it SUCKS. the white powder forming all over the element is a sure sign of electrical nightmares...

Smoker · #4 10-22-2013, 10:30 AM

Been all through this with the vintage saabs and veedubs that I was into previously. Nothing like running down the road and the wipers stop...quick pull over to spin the fuse in the holder and take off again.

I use a cleaner called deoxit before swapping in the copper/ceramic fuses. Seems to do well. If they're really bad I'll do a scrub with one of my stiff nylon 'tooth' brushes with deoxit on them.

Current 240 project needs the treatment. The fuses are all aluminum and have corrosion on them. The turn signals will work, then not, twist the fuse and 'spaaaark' they start working.

Glad we don't have an electric fuel pump to worry about

TnBob · #5 10-22-2013, 11:30 AM

I suggest Tarnex due to using it for yrs. One $5 bottle lasts for yrs too.

Diesel911 · #6 10-22-2013, 11:40 AM

The likely cost more and are harder to find but there is pointed Buss type Fuses in the Glass Tube that you can use.

Quote from the below Thread, post #3 and there is also a picture. "There is a third choice if dependability is more important to you than originality. Buss fuses are available in a "G" series made of stainless steel and glass to replace the ceramic fuses. These "G" series are the correct length, have the correct "pointed" ends and are available in various amperages. They never corrode or tarnish and may be more readily available from your local hardware store or NAPA. See the photo below."
http://www.mbca.org/forum/replacement-fuses

Even though the Ocean is only a few Miles away the Air is dry enough it does not have any obvious effect on My Fuses except that one of the Window Fuses lost a tip.
So I have had no issues using what I have Aluminum or otherwise.

When I go to the Junk Yard and I am not finding what I wanted I go around picking the Fuses and about 20 are so is only about $2 at the check out.
I have a few of the Buss type Fuses but in low amperage. I found them mostly in Volvos. Although you only might find one installed and the rest of the Fuses are the Ceramic bodied ones.

PackerEdgerton · #7 10-22-2013, 12:44 PM

I buy a bunch of the copper-alloy fuses with the plastic bodies (from NAPA) and then I swap all the metal strips over to the ceramic bodies.

I have found on high-amp fuses (e.g. Aux Fan), the plastic bodies will actually soften up!

Best,

Packman

jay_bob · #8 10-22-2013, 02:39 PM

When I had my 240D the bearings on the cabin air fan started tightening up, causing the amp draw to go up on the motor. The 16 A (plastic) fuse started to melt and soften. It let out a stink of burning plastic like nobody's business. Scared me to death.

On the point of cleaning the fuse box contacts, never sand or use anything abrasive (pencil erasers, contact point files, etc) on them. This destroys the plating on the contacts and they will corrode 10x worse in a matter of weeks.

funola · #9 10-22-2013, 03:00 PM

Quote:

Originally Posted by jay_bob

When I had my 240D the bearings on the cabin air fan started tightening up, causing the amp draw to go up on the motor. The 16 A (plastic) fuse started to melt and soften. It let out a stink of burning plastic like nobody's business. Scared me to death.

On the point of cleaning the fuse box contacts, never sand or use anything abrasive (pencil erasers, contact point files, etc) on them. This destroys the plating on the contacts and they will corrode 10x worse in a matter of weeks.

Are you sure the fuse box contacts are plated? I always thought they were made from a solid alloy of copper/brass.

Phil_F_NM · #10 10-22-2013, 03:39 PM

While you're in your fusebox, make sure your contact points aren't corroded at the base.
Three of the contacts in my car were corroded and the rivets broken. This is very common with dissimilar metals that conduct current. The problem, is that the riveted bases are a little more than an inch down into the box (on W114/115 and W123) and can be hard to clean. I soldered mine but had to be careful not to melt the base of the fusebox. once I got all the broken connections soldered back up, most of my electrical gremlins went away.

Phil Forrest

TnBob · #11 10-22-2013, 03:56 PM

My bad too. The fuse element isnt copper its brass on the replacements.

jay_bob · #12 10-22-2013, 04:00 PM

Quote:

Originally Posted by funola

Are you sure the fuse box contacts are plated? I always thought they were made from a solid alloy of copper/brass.

I believe they are brass plated copper. If you scrape away the brass the copper is exposed. In a high moisture environment (like under the hood of a car) the copper quickly corrodes. This drives up the contact resistance, which makes the copper heat up, which creates more oxidation, more contact resistance, more heat, thermal runaway, you get the point.

At work, the electrical equipment I engineer has large copper bus bars (think 1/4 inch thick by up to 7 inches wide) and those have to be silver or tin plated to keep them from corroding. (And it's often more than 1 of those bars laminated to get the proper current density ratings. The bus is rated from 2000 A to 6000 A.)

Everything gets silver plated except for equipment going into paper mills and wastewater treatment. The SO2 present in those environments destroys the silver plating, so those get tin plated bus.

eatont9999 · #13 10-22-2013, 06:30 PM

How about putting a dab of marine grease on the end of each fuse? I use it on all of my battery terminals and it helps keep the moisture and corrosion out.

jay_bob · #14 10-22-2013, 07:36 PM

Quote:

Originally Posted by eatont9999

How about putting a dab of marine grease on the end of each fuse? I use it on all of my battery terminals and it helps keep the moisture and corrosion out.

Excellent idea. Might just have to try that on my 124.