Do Blade fuses just get "old"?

[Cross-tie Walker]

Hi All,
I'm on a several day road trip and last night I discovered no headlight and no horn. I quickly discovered the 20 amp fuse controlling those had blown. I replaced it and put on another 400  miles today with no issues. My question to the experts is do these fuses just get old and wear out. (2007 Vintage) or should I be looking for a hidden reason for the problem. I was going through some almost torrential rain and wind on the southern Oregon coast that gives me some thought about that being the cause....but then again today I hit some pretty good rain, although not as heavy and everything is still lit and loud.
Any and all opinions welcome.    Thx

[oldbike54]

 Yes they do get old .

 Dusty

[beetle]

Fuses can fatigue like any other electrical components.

[rodekyll]

They might in a random sort of way, but I wouldn't consider them a replacement item like brake pads or spark plugs.  More like a coil or regulator.

[ibis1]

Everything gets old, but do fuses wear or weaken. I don't think so, but I can't say it's not possible. All fuses have or should have a margin in excess of the rated current in that circuit. Most automobiles go to the bone yard with dozens of fuses that are 10 to 20 years old and never failed. I would maintain that when a fuse blows, something caused it other than it's old and worn out. You could replace it and it may never blow again, which might lead you to believe it was simply worn out, but a simple drop of water may have shorted that circuit. I would not start ripping anything apart looking for a cause until a second fuse has blown. At that point it's safe to say, you have an issue. If you have a good meter which reads current, you might want to see exactly how much current those lights are drawing, because they can draw more current than they did when new due to excessive resistance build up over time. Good luck.

[Wayne Orwig]

Most blade fuses are a single stamped metal piece with plastic molded around it.
My original EV fuses had a metal blade on the left, one on the right, and the fuse element in the middle was staked to the two blades. Then a plastic piece was attached around it. I'd never seen anything like that. They were fragile and a couple of them just failed over the years from vibration and corrosion. I ended up replacing all of them with normal fuses.

[Kiwi_Roy]

Yes they do get old but that's no reason to blow
I tend to agree with Ibis1, the fuse blew because of an overload.

http://www.thisoldtractor.com/guzzi007/schematics/2008_California_Vintage.gif
There's a lot of wiring on the red/black wire downstream of the headlight relay, possibly an intermittent short in the tail light or around the brake switches.
You may go years before blowing another or it could show up as a recurring fault, if it does I like to replace the fuse with a large lamp then wiggle all the
connections until I see the light flash, better than replacing numerous fuses.

[charlie b]

The older glass fuses did have problems sometimes with combinations of high loads (not overload) and vibration.  Also, some of the really low capacity ones did not like vibrations.

The newer blade fuses should not create a problem like that.  What could have happened is that the blade contact area became small due to corrosion or such, increasing resistance and heat.  That little bit of increased heat could 'help' the fuse to blow if it was already near max.

Having said all that, I suspect you have an overload somewhere, or a short.

[Chuck in Indiana]

The older glass fuses did have problems sometimes with combinations of high loads (not overload) and vibration.  Also, some of the really low capacity ones did not like vibrations.

The newer blade fuses should not create a problem like that.  What could have happened is that the blade contact area became small due to corrosion or such, increasing resistance and heat.  That little bit of increased heat could 'help' the fuse to blow if it was already near max.

Having said all that, I suspect you have an overload somewhere, or a short.

I'll go with the corrosion theory, replace the fuse and forget about it *unless* it happens again. I've certainly seen fuses fail from corrosion. I'm pretty anal with corrosion with the Mighty Scura as it sits beside the ocean all the time. A few thousand miles ago, I coasted into a restaurant parking lot, dead as a doornail. Fortunately, I carry spare fuses. Never has happened again.

[lost]

With blade fuses the fuse can vibrate out and become loose, causing heat which would blow the fuse. If the bike were much older I would be concerned that the fuse holder had lost its spring and was making a loose connection. I have had that happen but it was on a 20 year old bike. Make sure when you install the fuse that it required some force which would intimate a tight connection.

[Guzzistajohn]

OMG!  A FUSE THREAD!

I'd stick with the dino fuses!

[Wayne Orwig]

Synthetic fuses are over priced, still blow if you pass too much power through them..




 

[twowings]

Where do I send my old fuses for a 'fuse analysis' ??

[Kiwi_Roy]

Where do I send my old fuses for a 'fuse analysis' ??

I think you are in jest, however looking at the blown fuse you can tell quite a bit.
Small gap, only a small overload
Large gap, short circuit
Discoloured plastic. loose connection

[Muzz]

My theory  would be that because a fuse by definition will run warm it will go through numerous heating/cooling cycles which MAY ultimately cause it to fatigue and blow at a lower voltage than indicated.

[oldbike54]

I think you are in jest, however looking at the blown fuse you can tell quite a bit.
Small gap, only a small overload
Large gap, short circuit
Discoloured plastic. loose connection

 No , he is in Tulsa 

 Sorry Roy 

 About this fuses not getting old , not in the sense of a wear item as RK also said . However , as with any conductor , after long hours of use the conducting material can get a bit brittle . There was a 15 amp on my Jackal that blew at 106K miles , and now at 130K hasn't blown again .

 Dusty

[Guzzistajohn]

So, does one change all the fuses in the fall when the riding season ends? Of do it in the spring, maybe St. Patrick's day when you plant your taters? I'm afraid my fuses will get old next winter

[oldbike54]

So, does one change all the fuses in the fall when the riding season ends? Of do it in the spring, maybe St. Patrick's day when you plant your taters? I'm afraid my fuses will get old next winter

 Depends , odd years Northern hemisphere , even years Southern . Of course someone will be along shortly to disagree 

 Dusty

[Kiwi_Roy]

 
  There was a 15 amp on my Jackal that blew at 106K miles , and now at 130K hasn't blown again .
 Dusty

Ha Dusty,
              All the fuses on the Jackal are 15 Amps
The start fuse sees 40 to 45 Amps when starting, they will get hot in a split second, melt in 1/4 second if the starter solenoid hangs up a little. It should have been a 20 at least for a safety margin.

Roy

[beetle]

Geez. It's not rocket science. What Kiwi Roy said. Little splatter, small overload. Could be due to bad connections elsewhere in the loom. Big splatter. Possible fault.
With regard to fatigue, a fatigued fuse will go open circuit even with current within spec. Now to be clear, I've never myself seen one on a bike. I've found plenty on other equipment, which is outside the scope of this thread, but it's not say it can't happen. Dusty's example. A fatigued fuse will usually go open at or near the end of the filament, with very little or no indication (splatter).

[beetle]

So, does one change all the fuses in the fall when the riding season ends? Of do it in the spring, maybe St. Patrick's day when you plant your taters? I'm afraid my fuses will get old next winter

You must replace all your fuses under the light of a blue moon, on Walpurgis night while holding a black dove in your right hand.

[Guzzistajohn]

You must replace all your fuses under the light of a blue moon, on Walpurgis night while holding a black dove in your right hand.

Holy shart! I hope my fuses make it that long. Now............wher e did I put that black dove?

[oldbike54]

Ha Dusty,
              All the fuses on the Jackal are 15 Amps
The start fuse sees 40 to 45 Amps when starting, they will get hot in a split second, melt in 1/4 second if the starter solenoid hangs up a little. It should have been a 20 at least for a safety margin.

Roy

 Well of course , I was just giving an example from experience .

 

Geez. It's not rocket science. What Kiwi Roy said. Little splatter, small overload. Could be due to bad connections elsewhere in the loom. Big splatter. Possible fault.
With regard to fatigue, a fatigued fuse will go open circuit even with current within spec. Now to be clear, I've never myself seen one on a bike. I've found plenty on other equipment, which is outside the scope of this thread, but it's not say it can't happen. Dusty's example. A fatigued fuse will usually go open at or near the end of the filament, with very little or no indication (splatter).

 Nothing is outside the scope of WG 

 My point was that yes , fuses can and do fatigue with age . Unusual for one to fail , but it can happen .

 Dusty

[Kiwi_Roy]

It's all Ben Franklins fault, the electrons are confused

http://www.allaboutcircuits.com/textbook/direct-current/chpt-1/conventional-versus-electron-flow/

[oldbike54]

 Thanks for making me even more con(fuse)d Roy 

 Dusty

[ITSec]

Well, I can't resist any longer - have to add my thoughts to this (as a one-time physics teacher and another stint as an electronics tech).

A fuse is basically like a light bulb - but with a very thick filament that is designed to hold up for a long time unless conditions exceed its design. Like any filament, the wire in a fuse is undergoing constant low-level stress even when conditions in the circuit are normal. Eventually, a fuse can fail due to this (as well as vibration when in a vehicle).

If an old fuse blows, replace it and keep an eye out for a while. If it blows a second time, you've got reason to start checking for all the things that can cause problems, like failing components, corroded connections, and so on.

[Guzzistajohn]

Well, I can't resist any longer - have to add my thoughts to this (as a one-time physics teacher and another stint as an electronics tech).

A fuse is basically like a light bulb - but with a very thick filament that is designed to hold up for a long time unless conditions exceed its design. Like any filament, the wire in a fuse is undergoing constant low-level stress even when conditions in the circuit are normal. Eventually, a fuse can fail due to this (as well as vibration when in a vehicle).

If an old fuse blows, replace it and keep an eye out for a while. If it blows a second time, you've got reason to start checking for all the things that can cause problems, like failing components, corroded connections, and so on.

You seem to be fairly knowledgeable, what does the black dove have to do with this?

[Muzz]

Depends , odd years Northern hemisphere , even years Southern . Of course someone will be along shortly to disagree 

 Dusty

As one out of left field on the backside of the planet I do neither. I carry a selection of fuses in a small container in my riding jacket. As a result of this I have never needed to use one.   12 years and counting.

[oldbike54]

As one out of left field on the backside of the planet I do neither. I carry a selection of fuses in a small container in my riding jacket. As a result of this I have never needed to use one.   12 years and counting.

 Like the spare beemer clutch cable I carried around for years , never a problem until of course leaving it at home . Broke the cable on the bike 1,000 miles from home , and 500 miles from any dealer . Bodged a solution involving a small U clamp , but still ...

 Dusty

[Guzzistajohn]

I've had the same spare throttle cable wire tied to the working ones on the cx for prolly 15 years.