How many of you have seen failed Panasonics!?

[keldeo]

In my experience, I've seen failed Taiwan/Chinese caps, obviously as I'm sure all of us had. I've also seen the defective Nichicon and Chemi Con series. Even seen failed Rubycons (MBZ I think?) if they are exposed to a lot of stress and heat. I've never seen failed Panasonics until now! Not just one, but 3! Also in seemingly random locations on the motherboard. Next to the RAM and CPU, but not t part of the VRM. It felt like I spotted a Unicorn, so I had to make this post. Motherboard is a IPIBL-LA. OEM from HP.

Unfortunately, I do not know the history behind this PC, it also had no HDD, so I don't have an estimate of the hours on it. I bought it for about $1, as it was on a pallet with nearly 40 PCs in total and I bought the entire pallet.

[stj]

FL do fail, they were never sold retail, just special order for motherboards.
probably too small for their spec so they got hot..

also, FC can leak from the base after a decade or 2.

[keldeo]

I see, I never knew that about the FCs. I guess given enough stress/heat/time any cap can fail, even Panny.

[PeteS in CA]

One of those bad caps in the first and second pic is in a sort of pocket formed by a memory DIMM, an inductor, and a connector and wires. If the inductor was hot the cap would get cooked. The bad cap in the third pic is in a corner formed by two heatsinks, i.e. two heat sources, with the hot air from one blowing on the cap.

With enough time, an electrolytic cap used well within its parameters will eventually fail. It may take 10 or 20 or 30 years, but they do dry out. In the same way, an X- or Y-cap exposed to many years of surges will eventually fail, and may fail ugly (crispy with a burnt smell).

[Wester547]

The combination of the external heat and internal heat (high ripple current) was probably enough to cause those Panasonic FLs to bloat and leak over time and use. Heat accelerates all chemical reactions, including hydrogen gas generated at the cathode.

Chemi-con’s KZG and KZJ series were notorious for bloating or otherwise failing even in storage. Nichicon’s early HM and HN series had similar issues. Rubycon’s MCZ (and MFZ) series were quite sensitive to heat, and the MBZ series, while a bit more durable, may not have tolerated long term thermal duress as much as their other longer life series. My take away is, these were all ultra low ESR series when they were in production (replaced by solid polymers today), and those capacitors were probably pushing electrolytics to the very edge of stability due to the complex chemistry, sacrificing some reliability for their performance…

[keldeo]

I see yeah definitely from the heat. Also, the PSU had some bloaded Ltecs, I'm sure that put stress on the motherboard caps.

Yeah I recall reading that ultra low wet caps were pushing the boundries, which is why they have a tendancy to be more failure prone,

[stj]

the problem is, FL were always used around the cpu heatsink.
so they always got cooked.