4700uF 25V replacement advice, please

[thebeerglass]

I've got a recently deceased Creative I-Trigue 2.1 3300 speaker system. There's a G-Luxon 4700uF, 25V , GR85°C 309C(M) leaking a nasty green goo onto the board (P/N: PBMS0420A0210). What would you recommend as a replacement? Thanks.

[selldoor]

Re: 4700uF 25V replacement advice, please

Well almost anything is going to be better so I would use this
http://cpc.farnell.com/panasonic/eeu...25v/dp/CA05160

Providing it fits the available space.

Are there any more of the same type - if one has gone others are likely to follow.

You need be meticulous about cleaning the board and maybe even have to change the wire links if they are corroded.

[stj]

Re: 4700uF 25V replacement advice, please

that's not leaking, it's glue

[Andrew F. Ali]

Re: 4700uF 25V replacement advice, please

What piece of electronic item is this and what symptoms are you observing for you to deduce there is afault in the power supply section???

[mariushm]

Re: 4700uF 25V replacement advice, please

Like stj says, the capacitor is probably OK.]

What you see there is a bit of white/cream glue that was used to keep the capacitor on the board before the board went through the machine that soldered everything on the bottom (wave soldering).

Some glues have a bad chemical formula, in time they "dry" out and turn dark brown and can become conductive, which is not good. In your case, this is probaby happened, and the glue as it became somewhat conductive and either became black from current going through it and heating it up or just from general heat around that area (from the rectifier for example).
You should desolder the large capacitor and use a blade or a chisel to scrape off that glue and make sure nothing is shorted by the glue and then if the capacitor looks to be in good condition, reconnect it in circuit.

If you want to replace it, you can pretty much replace it with any capacitor of reasonable quality. It filters the AC voltage at 120Hz so it doesn't have to be a very low esr capacitor, doesn't have to be something expensive. You can also get something with higher rating, for example 35v or 50v and you can also go a bit higher in capacitance if that's all they have at a store near you.

[thebeerglass]

Re: 4700uF 25V replacement advice, please

Thanks for the explanation, mariushm. I looked through the other photos on badcaps.net and it didn't look like the normal corrosive mess you get from leaking electrolyte. Other than the glue goo, the capacitor looks OK, and so do all the other ones on the board. I'll clean it up as you suggest and report back.

[thebeerglass]

Re: 4700uF 25V replacement advice, please

And that's all it needed. Having cleaned up the board and capacitor, the speaker system is now working again. Perhaps I'll start a forum called "badglue.net"! Thanks for your help.

[lexwalker]

Re: 4700uF 25V replacement advice, please

And that's all it needed. Having cleaned up the board and capacitor, the speaker system is now working again. Perhaps I'll start a forum called "badglue.net"! Thanks for your help.

Congrats, now your world of knowledge has just suddenly expanded. Degraded glue is one of the main culprits for hardware problems, and I've quite often run into them in my repair work. Often by just removing degraded glue, the equipment becomes working again. Of course, that is not the case all the time as secondary problems created by degraded glue are many including component failures and brown outs...