The Hall of Shame - Badcaps Photo Montage

[momaka]

Cool links. Thanks!

Originally Posted by Wester547

And that 15 year spec doesn't allude that the caps will outgas, leak, or bulge after 15 years either, only that they will very gradually dry out and very slowly go out-of-spec.

That's exactly what I mean.

Basically what the manufacturers are saying is you should expect about 15 years of trouble-free life... or thereabouts if the caps weren't abused (obviously the life should be derated according to operating conditions). It's a "recommendation", not requirement.

So in a setting with parts that have critical tasks - like industrial gear, for example, then you should expect to change any parts with electrolytic caps about every 15 years or less if you want pretty much guaranteed trouble-free operation.

But in consumer gear, we can see from field results (old computers, for example) that on average, *many* caps will last much longer than 15 years without problems whatsoever. In fact, even 20-25 years is not uncommon. By that time, typically the consumer item has been replaced a long time ago.

Originally Posted by Wester547

EDIT: Looking at the SMD capacitors in the link below that Per Hansson provided, SMD capacitors are the worst... those are known to dry out much faster than their through-hole next-of-kin. I'd give those wet SMD capacitors less than 15 years before they dry out.

They also tend to have worse ESR specs.

My guess would be that the process that bends the leads and smashes them so the caps become SMD is weakening the seals/bungs of the caps. Hence they dry out quicker. But that is just a speculation on my part.

The soldering process may also have something to do with it as well. I think through-hole caps tend to be exposed to less heat during soldering than SMD.

[Wester547]

But in consumer gear, we can see from field results (old computers, for example) that on average, *many* caps will last much longer than 15 years without problems whatsoever. In fact, even 20-25 years is not uncommon. By that time, typically the consumer item has been replaced a long time ago.

Well, that's assuming we aren't talking about the quaternary-ammonium salt series of old, such as Nichicon PL, PR, PF, PQ, PC, Chemi-con SXE, LXF, SXG, SXF, etc... I'm pretty sure every manufacturer had at least a couple and those were known to leak from the bungs and cause drove of issues well before 20-25 years were up. And they were quite common in 20-25 year old gear, both consumer and industrial. Rubber bungs will quickly deteriorate with that type of electrolyte composition, primarily due to the pH balance rising (EG, excessive alkalinity) over time in that type of electrolyte. Quaternary-ammonium salt electrolyte is still used in double-layer electrolytics.

They also tend to have worse ESR specs.

My guess would be that the process that bends the leads and smashes them so the caps become SMD is weakening the seals/bungs of the caps. Hence they dry out quicker. But that is just a speculation on my part.

The soldering process may also have something to do with it as well. I think through-hole caps tend to be exposed to less heat during soldering than SMD.

It's definitely possible. Wave soldering may be more stressful for the plastic base and rubber bung, but if the seal is compromised, not only may they dry out quickly, they may leak from the bung too, and that extremely acidic and corrosive electrolyte will quickly eat away at traces and even burn right through a multilayer PCB if the current draw is high enough in the circuit. The worst of all failures, IOW.

[RukyCon]

Originally Posted by ruky con

Dead CapXon's in a HP PSU.
http://www.badcaps.net/forum/attachm...1&d=1495451781

The power supply's OEM is Bestek.

[momaka]

Originally Posted by Wester547

Well, that's assuming we aren't talking about the quaternary-ammonium salt series of old, such as Nichicon PL, PR, PF, PQ, PC, Chemi-con SXE, LXF, SXG, SXF, etc... I'm pretty sure every manufacturer had at least a couple and those were known to leak from the bungs and cause drove of issues well before 20-25 years were up. And they were quite common in 20-25 year old gear, both consumer and industrial.

There are still car ECUs with these around. Depending on how the car was kept (i.e. indoors or outdoors and temperature extremes), I'm sure quite a few are still in service. I forgot which car manufacturer and model used Nichicon PL and PR, but there are a few. They are indeed problematic, but not the most terrible. I will still gladly use a used Nichicon PL/PR over a Sacon FZ

Originally Posted by ruky con

The power supply's OEM is Bestek.

You mean Bestec?
Bulged CapXon, Teapo, and Jamicon are quite common in older Bestec PSUs. Decent power supplies otherwise... though I am not a fan of the tan conductive glue in the older units. Newer ones moved to the white silicone, thankfully.

[Wester547]

Originally Posted by momaka

There are still car ECUs with these around. Depending on how the car was kept (i.e. indoors or outdoors and temperature extremes), I'm sure quite a few are still in service. I forgot which car manufacturer and model used Nichicon PL and PR, but there are a few. They are indeed problematic, but not the most terrible. I will still gladly use a used Nichicon PL/PR over a Sacon FZ

Lexus, Toyota, and Supra are a few.

The way those caps failed is very different from Sacon FZ. Instead of violently venting, bursting, and expelling their contents due to extreme and unimpeded H2 generation, they would leak from the bung and eat traces.

That said, it seems the issues with leaking from the bung aren't limited to the quaternary-capacitors. There were a multitude of 85ºC caps from the early-mid 90s, according to the threads below, by Nichicon (VR), Rubycon (TWSS/YK), Chemi-con (SM/SME), and Elna, which were notorious for leaking from the bung after 10-15 years, even in NOS equipment. Those too struggled to last 10-15 years, nevermind 20-25 years. SMD capacitors from Nichicon and Panasonic (from the late 80s-late 90s) also suffered from such issues. Something must have been amiss with the sealing rubber they were using because multiple brands were affected. They were quite commonplace in Mitsubishi CRT projectors and Zenith CRT TVs, but were found in plenty of other gear too. Seems the Panasonic through-hole 85ºC caps (from that timeframe) were thankfully unaffected.

http://www.badcaps.net/forum/showpos...63&postcount=1
http://www.badcaps.net/forum/showpos...85&postcount=3
http://www.badcaps.net/forum/showpos...07&postcount=9
http://www.badcaps.net/forum/showpos...94&postcount=1
http://www.badcaps.net/forum/showpos...12&postcount=1
http://www.badcaps.net/forum/showpos...8&postcount=12

I'm not trying to say that the beloved Japanese brands are crap or that all brands are created equal, but it's partly why I take the 15-year-max-life-spec given by manufacturers (due to aging rubber bungs) in earnest.

[RukyCon]

Originally Posted by momaka

You mean Bestec?

My bad.

[momaka]

Originally Posted by Wester547

The way those caps failed is very different from Sacon FZ. Instead of violently venting, bursting, and expelling their contents due to extreme and unimpeded H2 generation, they would leak from the bung and eat traces.

Yeah, I have a good few used Nichicon PR caps that have leaked from the bottom. Not a nice sight to see. And they stink too, especially when the electrolyte goes over solder and you try to melt the solder. Ugh.

Originally Posted by Wester547

That said, it seems the issues with leaking from the bung aren't limited to the quaternary-capacitors. There were a multitude of 85ºC caps from the early-mid 90s, according to the threads below, by Nichicon (VR), Rubycon (TWSS/YK), Chemi-con (SM/SME), and Elna, which were notorious for leaking from the bung after 10-15 years, even in NOS equipment. Those too struggled to last 10-15 years, nevermind 20-25 years.

Thanks for the info!

I've only heard of Nichicon VR going dry/high-ESR, but never anything about them leaking. Maybe that is why. Chemicon SME I am weary about, as I've seen a few bad ones in old electronics.

That means a lot of Sony CRT TVs and monitors from the 90s may be affected. I have quite a few late 90's Sony CRT monitors. Makes me curious to pull every Nichicon VR and Rubycon YK cap they have to check. I've pulled quite a few of these caps from discarded CRT TVs on the street (have about two or three complete board sets for various large Sony CRT TVs), but none of them appeared to be leaking or bad.

Originally Posted by Wester547

Seems the Panasonic through-hole 85ºC caps (from that timeframe) were thankfully unaffected.

That would be great to hear. I still have a few pulled caps from a mid-90's Panasonic CRT TV. May use some of them to recap a 17" CRT monitor that has mostly sentimental value to me (and not to mention unique ChromaClear screen with amazing colors).

Originally Posted by Wester547

I'm not trying to say that the beloved Japanese brands are crap or that all brands are created equal, but it's partly why I take the 15-year-max-life-spec given by manufacturers (due to aging rubber bungs) in earnest.

I suppose the caps made in the late 70's and early 80's were just better then. Otherwise I don't know how my dad's Sony TA-F70 amplifier is still working. The thing is over 30 years old, and lately has seen a lot of use due to my sister's kid listening to music on it all the time. It's amazing to see that, as I vaguely remember when I was his age and using that amp to listen to music.

[Wester547]

Originally Posted by momaka

That means a lot of Sony CRT TVs and monitors from the 90s may be affected. I have quite a few late 90's Sony CRT monitors. Makes me curious to pull every Nichicon VR and Rubycon YK cap they have to check. I've pulled quite a few of these caps from discarded CRT TVs on the street (have about two or three complete board sets for various large Sony CRT TVs), but none of them appeared to be leaking or bad.

Late 90s are probably okay. I would be leary of those made from the early to mid 90s, especially the smaller diameter ones, as those seem to suffer the most. Not saying they are guaranteed to leak though.

I suppose the caps made in the late 70's and early 80's were just better then. Otherwise I don't know how my dad's Sony TA-F70 amplifier is still working. The thing is over 30 years old, and lately has seen a lot of use due to my sister's kid listening to music on it all the time. It's amazing to see that, as I vaguely remember when I was his age and using that amp to listen to music.

Maybe the rubber bungs are coated with epoxy? Or the rubber bungs they used back then were most resistant to oxidization and the ozone layer. That, or they were just tighter around the leads.

[RukyCon]

Originally Posted by Wester547

That said, it seems the issues with leaking from the bung aren't limited to the quaternary-capacitors. There were a multitude of 85ºC caps from the early-mid 90s, according to the threads below, by Nichicon (VR), Rubycon (TWSS/YK), Chemi-con (SM/SME), and Elna, which were notorious for leaking from the bung after 10-15 years, even in NOS equipment. Those too struggled to last 10-15 years, nevermind 20-25 years. SMD capacitors from Nichicon and Panasonic (from the late 80s-late 90s) also suffered from such issues. Something must have been amiss with the sealing rubber they were using because multiple brands were affected. They were quite commonplace in Mitsubishi CRT projectors and Zenith CRT TVs, but were found in plenty of other gear too. Seems the Panasonic through-hole 85ºC caps (from that timeframe) were thankfully unaffected.

That's interesting, i wonder why i have not come across any of these failed capacitors as i been taking apart a lot of broken stuff from 90s and the only failed capacitor i came across was a nichicon VX but it had not leaked anything

[momaka]

Originally Posted by Wester547

Maybe the rubber bungs are coated with epoxy? Or the rubber bungs they used back then were most resistant to oxidization and the ozone layer. That, or they were just tighter around the leads.

I have no idea. Other than opening the amp about 3 years ago to dust it out, it's never been serviced before. Quite impressive for close to 38 years of service! Only the input selector switches are getting old and grumpy. Can't blame them, though.

[Wester547]

Originally Posted by ruky con

That's interesting, i wonder why i have not come across any of these failed capacitors as i been taking apart a lot of broken stuff from 90s and the only failed capacitor i came across was a nichicon VX but it had not leaked anything

I don't think Nichicon VX is affected. I've pulled 23-year old (5mm-8mm) Nichicon VXes out of Sony VCRs which haven't leaked and tested fine. AFAIK, this would affect 10mm diameter and smaller Nichicon VR in early-mid 90s equipment, but this is just my observation based on my limited experience and the aforementioned experience of others. It may not have been the rubber at all. Another possibility is that the electrolyte solution all the "big" manufacturers (except Panasonic) were using back then, for their 85ºC capacitors, had a very highly "concentrated" portion (conductive acids, salts) and a very small "unconcentrated" portion (free vapor), and very little water in the electrolyte too. This is good in that it reduces the internal vapor pressure and slows the evaporation rate (due to the lack of free vapor and water in the electrolyte, although one could add certain sugars in the composition to retard evaporation), but it's bad because as the rubber ages, the liquid electrolyte is less likely to evaporate and more likely to leak around the bung (unless of course the vent stamp or rubber seal is destroyed, in which case leakage is inevitable).

Again, this is just my conjecture as to why they leak. 38 years of service is impressive. If those caps were to die or leak the next year or so, it would be understandable.

[RukyCon]

Originally Posted by Wester547

I don't think Nichicon VX is affected. I've pulled 23-year old (5mm-8mm) Nichicon VXes out of Sony VCRs which haven't leaked and tested fine. AFAIK, this would affect 10mm diameter and smaller Nichicon VR in early-mid 90s equipment, but this is just my observation based on my limited experience and the aforementioned experience of others. It may not have been the rubber at all. Another possibility is that the electrolyte solution all the "big" manufacturers (except Panasonic) were using back then, for their 85ºC capacitors, had a very highly "concentrated" portion (conductive acids, salts) and a very small "unconcentrated" portion (free vapor), and very little water in the electrolyte too. This is good in that it reduces the internal vapor pressure and slows the evaporation rate (due to the lack of free vapor and water in the electrolyte, although one could add certain sugars in the composition to retard evaporation), but it's bad because as the rubber ages, the liquid electrolyte is less likely to evaporate and more likely to leak around the bung (unless of course the vent stamp or rubber seal is destroyed, in which case leakage is inevitable).

Again, this is just my conjecture as to why they leak. 38 years of service is impressive. If those caps were to die or leak the next year or so, it would be understandable.

Still does not explain why i have not come across any so far. Though i have not come across any nichicon VR capacitors in any older electronics yet.

[Behemot]

Have not seen any such bad YK either.

[jazzie366]

Originally Posted by ruky con

Still does not explain why i have not come across any so far. Though i have not come across any nichicon VR capacitors in any older electronics yet.

Funny you should say this, just pulled some Nichicon VX (axial style) out of an Ampeg J-12R, both pushing their bungs out. Not leaking (yet) but the bungs are on their way out. Surprisingly, they test just fine, except for the fact the bungs are being pushed out.
Anyone know why this would happen?

[Wester547]

Originally Posted by Behemot

Have not seen any such bad YK either.

There are examples of bad YK, albeit on another forum. One of the threads I linked to mentions lots of bad Rubycon "YX", but I'm fairly certain the OP of that thread meant "YK", as there is no YX series and it would be easy to mistake a "K" for a "X" if the text on the sleeve is obscured in any way.

Again, the date codes seem to be early to mid 90s, not late 90s. I am not saying all are guaranteed to leak, only that going off of those threads and some other examples, it definitely was an issue a while back. Caps that are pushing their bungs out have likely experienced electrolyte failure. It sounds like they are outgassing through the rubber seal to me, but they are axial capacitors which I don't think are affected by the aforementioned issues regarding rubber bungs.

[momaka]

Originally Posted by Wester547

Again, this is just my conjecture as to why they leak. 38 years of service is impressive. If those caps were to die or leak the next year or so, it would be understandable.

The Nichicon caps for the pre-amps have a slight bulge on top already. But they've had it for at least 3 years now, lol.
Amp still working, though - and even harder than before. With my sister's kid, it's ON at least 4-6 hours a day.

I would open it and recap it, if it wasn't so hard to take the whole front panel apart. That, and the fact that where it is located, I would have to make note of all cap values and then order them when I come to visit them again in a year. I also only have some basic soldering equipment and tools there.

[Behemot]

Them on Americas (continents)? If so, can take it one way and send the other by some courier.

[Wester547]

Originally Posted by momaka

The Nichicon caps for the pre-amps have a slight bulge on top already. But they've had it for at least 3 years now, lol.
Amp still working, though - and even harder than before. With my sister's kid, it's ON at least 4-6 hours a day.

So have they actually outgassed or did the electrolyte simply expand a tad from all that heat? Or is the bulge so slight that it's difficult to distinguish between "factory anomaly" and "pressure-relief vent in action" ? They are 85ºC caps I take it, so I wouldn't blame them for failing either way after all those years of thermal duress.

[momaka]

Originally Posted by Behemot

Them on Americas (continents)? If so, can take it one way and send the other by some courier.

Other way around: I'm in the USA, they are in Eastern Europe.
No one but me would think it is worth doing that. If I don't fix electronic things in my family, no one else does and the broken stuff get thrown away.

Originally Posted by Wester547

So have they actually outgassed or did the electrolyte simply expand a tad from all that heat? Or is the bulge so slight that it's difficult to distinguish between "factory anomaly" and "pressure-relief vent in action" ?

Probably one of the first two. My dad used to take this amp to weddings way back in the day (like 20-30 years ago) and run it pretty hard for days. They could have bulged then. Or they could have gassed up over the years.

That said, the amp doesn't run hot at all - in fact, not even warm at normal listening levels. So those caps probably have not seen much heat abuse.

Worth noting is that those caps don't have pressure-relief vents - at least not the scorched/engraved ones on top like modern ones anyways. I'll post pictures someday when I have time... and maybe I should open it again and take better ones too, while at it. The ones I have are just okay.

[Behemot]

Can send ya the caps while there, if those aren't some strange sizes I don't carry (and neither my suppliers with stock). That should take few days by airmail.