Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

One possiblity is if someone had the speaker unplugged on the back of chassis. With no load on the high voltage winding this would allow the voltage to build up to the maximum possible.(450V+)

Richard

Was it an original cap or one that someone has added in? If a replacement it may have been installed with the wrong polarity or with to low of a voltage rating. Either of these two situations will cause exploded capacitors.
Greg

:Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

:Was it an original cap or one that someone has added in? If a replacement it may have been installed with the wrong polarity or with to low of a voltage rating. Either of these two situations will cause exploded capacitors.
:Greg
:
:
::Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

The owner told me they were listening to it and it just quit playing, I would think they must have heard it explode but ????. It is a replacement, (original was a metal can on top) being cardboard and under the chassis it blew all apart.

::Was it an original cap or one that someone has added in? If a replacement it may have been installed with the wrong polarity or with to low of a voltage rating. Either of these two situations will cause exploded capacitors.
::Greg
::
::
:::Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

More than likely installed with reversed polarity. Double check the schematic so you dont make the same mistake.
Greg

:The owner told me they were listening to it and it just quit playing, I would think they must have heard it explode but ????. It is a replacement, (original was a metal can on top) being cardboard and under the chassis it blew all apart.
:
:
: ::Was it an original cap or one that someone has added in? If a replacement it may have been installed with the wrong polarity or with to low of a voltage rating. Either of these two situations will cause exploded capacitors.
:::Greg
:::
:::
::::Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

Thanks for the info.

:More than likely installed with reversed polarity. Double check the schematic so you dont make the same mistake.
:Greg
:
:
:
::The owner told me they were listening to it and it just quit playing, I would think they must have heard it explode but ????. It is a replacement, (original was a metal can on top) being cardboard and under the chassis it blew all apart.
::
::
:: ::Was it an original cap or one that someone has added in? If a replacement it may have been installed with the wrong polarity or with to low of a voltage rating. Either of these two situations will cause exploded capacitors.
::::Greg
::::
::::
:::::Looking for some help with a Zenith 6S223 I'm working on. When I took the chassis out of the radio and turned it over I found that C-16 (8MFD) had exploded at sometime in the past covering the entire chassis with capacitor particles. My question is what would cause this and what should I look for because of the explosion.

I tend to agree that reverse polarity is the likely cause. A radio may play, after a fashion, with one of the e-caps wired backwards, but the cap will likely leak or explode.

I've even encountered an e-cap wired backwards by the factory. It was a modern tube-type hi-fi amp, not an antique radio. The cap was a Sprague Atom, which leaked a white paste - it didn't explode.

Caps also explode when they get old and leak. They get hot from the leakage. Seeing as this was a replacement, it may not have gotten leaky. You can tell whether the cap was installed incorrectly or not by looking at its remains, if any exist where it was wired in. A rubber gasket would indicate the positive side (usually). You have to know how the cap was constructed to tell for sure. Some have a bunch of leads coming out one end and are sealed up with tar. Any one of these leads could be positive or negative depending upon how the cap was designed. Also, unless you do find a metal unit on top of the chassis, Zenith did use cardboard tube caps under the chassis which had rubber leads coming out of them.

Also, if someone replaced the cap with a lower voltage cap, it may work for a while and then explode. All suggestions given by everyone are good ones.

Thomas

Thanks to all, great info.

Merry Christmas!

:Caps also explode when they get old and leak. They get hot from the leakage. Seeing as this was a replacement, it may not have gotten leaky. You can tell whether the cap was installed incorrectly or not by looking at its remains, if any exist where it was wired in. A rubber gasket would indicate the positive side (usually). You have to know how the cap was constructed to tell for sure. Some have a bunch of leads coming out one end and are sealed up with tar. Any one of these leads could be positive or negative depending upon how the cap was designed. Also, unless you do find a metal unit on top of the chassis, Zenith did use cardboard tube caps under the chassis which had rubber leads coming out of them.
:
:Also, if someone replaced the cap with a lower voltage cap, it may work for a while and then explode. All suggestions given by everyone are good ones.
:
:Thomas

I tend to agree with Thomas but my question is it seems like this cap has gone more than once so there may be a voltage issue OR another problem causing this cap to go. WHen I have a cap that blows more than 2 times, I would make sure the voltage to it is correct. I have seen circuits where the normal voltage is say 30 volts and the cap rating is 35 volts which is too close for me.

Joe

:Caps also explode when they get old and leak. They get hot from the leakage. Seeing as this was a replacement, it may not have gotten leaky. You can tell whether the cap was installed incorrectly or not by looking at its remains, if any exist where it was wired in. A rubber gasket would indicate the positive side (usually). You have to know how the cap was constructed to tell for sure. Some have a bunch of leads coming out one end and are sealed up with tar. Any one of these leads could be positive or negative depending upon how the cap was designed. Also, unless you do find a metal unit on top of the chassis, Zenith did use cardboard tube caps under the chassis which had rubber leads coming out of them.
:
:Also, if someone replaced the cap with a lower voltage cap, it may work for a while and then explode. All suggestions given by everyone are good ones.
:
:Thomas

Hi

There is no reason for a good cap to blow as long as polarity & voltage are correct. Voltage out of the 5Y4 is 322 on the schematic. You can use 10 mf @ 450 volt caps as replacement.

Be sure the speaker is connected and rectifier isn't shorted.

http://www.nostalgiaair.org/PagesByModel/208/M0025208.pdf

Norm

:I tend to agree with Thomas but my question is it seems like this cap has gone more than once so there may be a voltage issue OR another problem causing this cap to go. WHen I have a cap that blows more than 2 times, I would make sure the voltage to it is correct. I have seen circuits where the normal voltage is say 30 volts and the cap rating is 35 volts which is too close for me.
:
:Joe
:
::Caps also explode when they get old and leak. They get hot from the leakage. Seeing as this was a replacement, it may not have gotten leaky. You can tell whether the cap was installed incorrectly or not by looking at its remains, if any exist where it was wired in. A rubber gasket would indicate the positive side (usually). You have to know how the cap was constructed to tell for sure. Some have a bunch of leads coming out one end and are sealed up with tar. Any one of these leads could be positive or negative depending upon how the cap was designed. Also, unless you do find a metal unit on top of the chassis, Zenith did use cardboard tube caps under the chassis which had rubber leads coming out of them.
::
::Also, if someone replaced the cap with a lower voltage cap, it may work for a while and then explode. All suggestions given by everyone are good ones.
::
::Thomas

Just a quick update on this radio. I did a complete re-cap and replaced the line cord, with cloth covered cord. I found a spot on the line cord that had melted (not the original cord) both sides. My guess, it was laying on a metal heater. And is now playing great. I believe the short in the line cord caused the cap to explode. Anyone have any thoughts on my reasoning, does it sound possible?

:Hi
:
: There is no reason for a good cap to blow as long as polarity & voltage are correct. Voltage out of the 5Y4 is 322 on the schematic. You can use 10 mf @ 450 volt caps as replacement.
:
: Be sure the speaker is connected and rectifier isn't shorted.
:
:http://www.nostalgiaair.org/PagesByModel/208/M0025208.pdf
:
:Norm
:
::I tend to agree with Thomas but my question is it seems like this cap has gone more than once so there may be a voltage issue OR another problem causing this cap to go. WHen I have a cap that blows more than 2 times, I would make sure the voltage to it is correct. I have seen circuits where the normal voltage is say 30 volts and the cap rating is 35 volts which is too close for me.
::
::Joe
::
:::Caps also explode when they get old and leak. They get hot from the leakage. Seeing as this was a replacement, it may not have gotten leaky. You can tell whether the cap was installed incorrectly or not by looking at its remains, if any exist where it was wired in. A rubber gasket would indicate the positive side (usually). You have to know how the cap was constructed to tell for sure. Some have a bunch of leads coming out one end and are sealed up with tar. Any one of these leads could be positive or negative depending upon how the cap was designed. Also, unless you do find a metal unit on top of the chassis, Zenith did use cardboard tube caps under the chassis which had rubber leads coming out of them.
:::
:::Also, if someone replaced the cap with a lower voltage cap, it may work for a while and then explode. All suggestions given by everyone are good ones.
:::
:::Thomas

A short in the line cord did not likely cause your cap explosion. It is good that you found it, though. Capacitors explode when steam pressure is built up within them. This takes a bit of time--the unit must heat up, first. Of course if you strike the cap with lightning, it'll explode right away, but then, so would anything else including a tree (I saw this once....it was awesome, though I kind of felt bad about the tree).

Thomas