JVC AX-Z911 right ch. broken, caps gone, voltage?

[TuomasH]

Hello all, I hope someone can recognize these capasitors, these are:

C425, C426: EEW6307-108 1000MF electro
and

C427, C428: EEW3502-478 4700MF electro






As you can see I think these electrolyte capacitors are broken. Funny thing is that only the right channel is distorted, left channel still works beautifully.

What I would like to know what voltage these parts use? Service manual is blank on these two caps, these are the only ones in the list which have no voltage marked! I am a newbie with this but be assured I won't let go of this amp without a fight. Perhaps there are even more components broken but these four are the most obvious ones.

Also if someone know sources for these caps or identical from different manufacturer please reply.

Thank you for your time!

Br,

Tuomas

[ostripper]

JVC AX-Z911BK SM Service Manual free download, schematics, eeprom, repair info for electronics

There's your schema. Caps are all 63WV. Could be replaced with same or 80wv.
Consider , it might not be the caps causing failure.
OS

PS - If electrotanya give problems DL'ing ... it's in my "new material" on my site.

[Tekko]

That brown stuff is more likely glue, cap guts looks more like water mixed with paper soup.

[adason]

clean all the potentiometers, switches and connectors in signal path first
before you replace caps

[Tekko]

Caps are generally okay as long as they havent bulged.

[TuomasH]

Originally Posted by Tekko

Caps are generally okay as long as they havent bulged.

Tekko: Take a look at this: Various blown capacitors - I am quite certain that the brown stuff is not glue because it wasn't there last time when I dismantled and cleaned this amplifier. Like I said I already have the service manual, thanks anyway Ostripper for posting it. By the way Ostripper, these caps are not the same, the first pair is 1100 microfarads and the second is 4700 microfarads. I suppose there might be some reason for having that big difference. Then again I am not sure what is the possible effect if I replace them with higher F/WV value caps. I found a source for the original caps but the seller does not ship them to internationally (USA->EU).

If someone knows a good European source for this type of caps please let me know.

[ostripper]

1100 uf ??? did not know they make those ? schema says 2 X 1000u. max rail voltage in main ps is +/-54v, 63V is standard OEM derating value for this voltage. I also have a "super A" JVC w/55v rails. It has a pair of 6800u-80V caps that I upgraded it to. It HAD ( 2 X 6800u/63V).

You are right , not all caps will "bulge" ... just leak slowly from the bottom and make a dang mess ... my Nikko had your exact "brown mess" around it's caps .

PS - fit the largest F/WV value you can in them holes !! 1k uf's are for the regulated supply. 4.7Kuf's are the "main dirty rails -54V".

OS

[TuomasH]

Originally Posted by ostripper

1100 uf ??? did not know they make those ? schema says 2 X 1000u. max rail voltage in main ps is +/-54v, 63V is standard OEM derating value for this voltage. I also have a "super A" JVC w/55v rails. It has a pair of 6800u-80V caps that I upgraded it to. It HAD ( 2 X 6800u/63V).

You are right , not all caps will "bulge" ... just leak slowly from the bottom and make a dang mess ... my Nikko had your exact "brown mess" around it's caps .

PS - fit the largest F/WV value you can in them holes !! 1k uf's are for the regulated supply. 4.7Kuf's are the "main dirty rails -54V".

OS

Hey! You are correct! I must have looked something else when I copied that 1100uF, it is 1000uF. Thanks for your advice! Now if only I could find a place which sell and ship those 6800 caps..

[ostripper]

mouser Mouser Electronics - Electronic Component Distributor - they have every nichicon capacitor line.

In fact, here are the 4700's ... Mouser Electronics - Electronic Component Distributor 4700u 63v

OS

[nigelwright7557]

Those caps are cheap and easy to change so I would change them anyway.
Electrolytics dont have a massive life anyway so are probably well past their sell by date.