Fuse melting, but not blowing?
#1
Drifting
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Fuse melting, but not blowing?
I have had an issue that recently began in my '84. My heater blower motor fuse actually melts the plastic body of the fuse, but the electrical connection part of the fuse does not blow.
The first one, I thought perhaps I had a faulty fuse, but then my replacement fuse melted to the point where the fuse was too short to make contact, but it never blew either fuse.
Fuse gets HOT upon reinstall, but does not blow.
No other effected circuits, so I am not thinking the usual ground issues, just the one.
Fan works great when a new fuse is installed, no other issues.
Any ideas?
The first one, I thought perhaps I had a faulty fuse, but then my replacement fuse melted to the point where the fuse was too short to make contact, but it never blew either fuse.
Fuse gets HOT upon reinstall, but does not blow.
No other effected circuits, so I am not thinking the usual ground issues, just the one.
Fan works great when a new fuse is installed, no other issues.
Any ideas?
#3
Drifting
I think!, but I am not sure,
that if you have high resistance (loose connection) on the load side spade and not the bat side, it may cause it to over heat and melt.
Just a guess
that if you have high resistance (loose connection) on the load side spade and not the bat side, it may cause it to over heat and melt.
Just a guess
#4
A slightly bad connection at either side of fuse will slightly limit the current and generate lots of heat. You need to clean the fuse holder and possibly bend the contacts in to better grip the fuse.
#6
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BTDT. Upon inspection there was an some metal from the previous fuse in the fuse holder, causing poor contact. Cleaned the fuse holder with fine grit sanding paper (fold over a few times) until shiney and no more problems since then.
#7
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Heat at the fuse is always poor contact on one or both fuse contacts. Usually between the fuse and its connectors, but sometimes between the connectors between the fuse holder and wires behind the panel.
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#8
Drifting
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I'll clean the contacts, hopefully that's it. I had the fuse panel out once before, that was enough.
Thanks for the ideas
Thanks for the ideas
#9
Burning Brakes
The crappy name brand (Busmann sp?) fuses you can get at auto stores/walmart are made from plastic. Mine melted regularly. I found a seller on eBay with "European fuses.". They're reasonably priced - come in blister packs if maybe 16 or 20. Best of all, the ones I found are ceramic, just like the originals in my '78.
#10
The plastic ones are probably safer. In the case of the ceramic ones, you can have a bad contact, generate lots of heat without the fuse showing any sign. In the case of the plastic one the fuse melts and ceases to push on the contacts and the circuit is broken forcing you to investigate before the heat causes a fire.
Just a theory.
Just a theory.
#11
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The plastic ones are probably safer. In the case of the ceramic ones, you can have a bad contact, generate lots of heat without the fuse showing any sign. In the case of the plastic one the fuse melts and ceases to push on the contacts and the circuit is broken forcing you to investigate before the heat causes a fire.
Just a theory.
Just a theory.
#12
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The crappy name brand (Busmann sp?) fuses you can get at auto stores/walmart are made from plastic. Mine melted regularly. I found a seller on eBay with "European fuses.". They're reasonably priced - come in blister packs if maybe 16 or 20. Best of all, the ones I found are ceramic, just like the originals in my '78.
Chinese no brand name ATC fuses are often made with poor fuse accuracy, poor materials/plating (including the plastic compounds) and even incorrect blade thickness/dimensions - these fuses cause problems (heating) due to poor connections and may damage the fuseholders permanantly... I assume similar is true of Chinese barrel fuses...
Alan
#13
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I got a bunch of Bussman fuses from my work, when I pulled out my fuse panel, and they were the wrong length. They were all too long, and I could just barely make them work. I was very unhappy with the quality control they showed.
The red one on the left is a new, improper length fuse.
The red one on the left is a new, improper length fuse.
#14
Nordschleife Master
#15
Burning Brakes
Bussman is actually a premium brand - ATO/ATC fuses are supposed to be made of plastic - it is not a sign of poor quality. Bussman & Littlefuse are the 2 ATC brands I recommend. For the Barrel style fuses (<85) The plastic should be quite fine - though the originals were ceramic. What matters most are the dimensions, metallic composition, plating & fuse element accuracy. If the fuse gets hot enough to melt the plastic you have a bigger problem which you should solve...
Chinese no brand name ATC fuses are often made with poor fuse accuracy, poor materials/plating (including the plastic compounds) and even incorrect blade thickness/dimensions - these fuses cause problems (heating) due to poor connections and may damage the fuseholders permanantly... I assume similar is true of Chinese barrel fuses...
Alan
Chinese no brand name ATC fuses are often made with poor fuse accuracy, poor materials/plating (including the plastic compounds) and even incorrect blade thickness/dimensions - these fuses cause problems (heating) due to poor connections and may damage the fuseholders permanantly... I assume similar is true of Chinese barrel fuses...
Alan
Just saying.