Yamaha CA-1000III Repair

J

joshcain

New Member
Hello,

New member here. I'm an American living in Japan and I recently picked up a Yamaha CA-1000III integrated amp locally. It's fully intact, visually perfect, all original. Everything works perfectly, but it does have one (major) operating fault. After playing for a few minutes, it will abruptly stop. I must power cycle in order to reset the relays and it will operate normally again for a few minutes, and then abruptly stop. Obviously I don't do that for fear of damaging something.
According to the manual, the protective circuit is kicking in. I do not know the reason why. It's not the speakers or any external component.
Any advice on what may be the cause? I'm mulling over whether to replace components myself, and if so, which components. Ebay has a kit to replace ~all components if I want to do a full re-cap. Anyone have any experience with these kits? https://www.ebay.com/itm/166091544133
Wife wants me to take it to a Yamaha pro to repair, but I think the cost could be high for a full refurb, which is what they will probably recommend.
Is a full refurb the best move? Is doing a full re-cap myself a heavy lift? I'm pretty handy but don't have equipment beyond a soldering iron and a multimeter. I would love to get it working myself, but I don't want to cause any damage of course.
Thoughts, ideas, and advice?
Thanks!

Josh
 
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Hey Josh, that Yamaha is a really nice integrated amp and if it's going to be your first foray into the world of restoration and repair it may be a bit of a heavy lift. I only say that because this kind of stuff isn't really as simple as it may at first seem. Unless you either have prior experience doing this kind of work, or, you have a lot of discipline and patience - and can follow directions from those here who may offer it, you'd be better off having someone else more experienced do the job for you. I did my CA800 about two years ago and it was rather involved. A lot of parts need to be updated and the "flip" and rotary switches on the front are prone to corrosion in a really bad way for the CA series Yamaha. I had to disassemble and clean at least 8 or more of those switches on the CA800 and it's a lot of work. Then you have the electrical adjustments - which can be kind of tricky if you're just learning. All of this is not impossible for the newbie but those qualities I mentioned above are an absolute necessity, I believe, for success.
After the switches are removed from their respective boards the have to be dis assembled and cleaned completely with DeOxit. I had to use emory paper as well to get the copper contacts back into shape. The little sliders on top of the switch contacts have to be soaked in DeOxit as well. Again the emory paper comes in handy for this also. As I said, a lot of work if you want to do it right. These units are prone to this corrosion and can experience intermittencies in multiple places (switches) because of it.
On the other hand there are a lot of people here on AK that are Yamaha fans, as I myself am, and would be glad to help you with your restoration or repairs. Just remember to take your time, listen to what others suggest and don't get ahead of the help being given. Do that and you'll find people glad to help you along. This kind of stuff takes time - be patient, take TONS of pictures in case you forget where something came from or goes back to, take notes, and double check your work. This is a great site and it's great to have you here.
** For some reason I can't upload any pics of the work I did - or else I would have. I've been trying, and they're small, but no go. Apologies.
Ganbatte yo!
 
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joshcain said:
New member here. I'm an American living in Japan and I recently picked up a Yamaha CA-1000III integrated amp locally
Click to expand...
CA-1010 -- Nice unit..
joshcain said:
Ebay has a kit to replace ~all components if I want to do a full re-cap. Anyone have any experience with these kits? https://www.ebay.com/itm/166091544133
Click to expand...
Maybe, maybe not.. No I don't waste my time with those over priced kits.

Judging by you initial description. I'd wager you have a bad solder connection most likely on the power supply sheet.
 
Whatever you do, please do not start carpet changing components hoping the problem will go away. You’ll end up damaging the unit and change its signature sound. The best advice (diagnosis) was given by @avionic above, there’s probably a bad (cold, cracked, etc.) solder joint(s) somewhere that acts up when it gets warmed up. First and foremost, find someone who can reflow all the solder joints in that unit, it’s not as trivial as it sounds, and take it from there. I’d offer to look at it for you but barring occasional pointers, due to heavy work commitments (unrelated) this year, I’m unable to.

Just as an FYI, of all the hundreds of caps I’ve replaced, I’ve never had a single bad or out of spec one in Japan. It must be the weather, so stay away from those overpriced eBay stuff. If anything, re-capping should be one of your last worries after everything else works. I have, however, seen horrendous solder joint conditions that made me wonder how the amps even worked. Cleaning and refurbing the physical aspects of the amp (switches, volumes, solder connections, cables, RCA connector connections, etc.) would be my priority unless of course you know for a fact that a component is bad. Good luck.
 
I'm going to do some basic troubleshooting and open the cabinet/review circuit cards as needed this weekend.
One thought - I think what's happening is that the protect circuit is kicking in. The reason I think it's the protect circuit kicking-in is that powering off and powering on again fixes the issue (temporarily), so I feel like the relay resets, then a high current or other condition causes it to engage again after power on.
How can I confirm that is actually what's happening?
Aside from excessive current draw, what else causes the protect circuit relay to engage?
I'm using two 8-ohm Sansui SA-30 speakers. They work, but I cannot say with 100% certainty they are not causing the issue. Is it possible that the speaker impedance may have declined over time and now they draw excessive current and cause the high-current protect circuit to engage? I'm going to measure speaker resistance with a multimeter to get a rough idea.
Anyway, I'm going slow and cautious trying to determine the problem and fix.
Thanks for all the advice.
 
joshcain said:
How can I confirm that is actually what's happening?
Aside from excessive current draw, what else causes the protect circuit relay to engage?
I'm using two 8-ohm Sansui SA-30 speakers. They work, but I cannot say with 100% certainty they are not causing the issue. Is it possible that the speaker impedance may have declined over time and now they draw excessive current and cause the high-current protect circuit to engage? I'm going to measure speaker resistance with a multimeter to get a rough idea.
Anyway, I'm going slow and cautious trying to determine the problem and fix.
Thanks for all the advice.
Click to expand...
Does it go into protection with the speakers disconnected ?

Three possibilities.
1. DC present at one or both of the amplifier outputs.
2. faulty protect circuit .
3. Power supply for the protect circuit.
 
avionic said:
Does it go into protection with the speakers disconnected ?

Three possibilities.
1. DC present at one or both of the amplifier outputs.
2. faulty protect circuit .
3. Power supply for the protect circuit.
Click to expand...
How can I tell if it goes into protect with speakers disconnected? I'm relying on the meters and speakers quitting to see when it goes to protect.
 
When the amplifier is in protect mode..

1. Check the DC voltage at LI and RI pins on the power supply board. Near the relay - towards the middle of the board. The closer to zero volts the better.
 
joshcain said:
How can I tell if it goes into protect with speakers disconnected? I'm relying on the meters and speakers quitting to see when it goes to protect.
Click to expand...
Listen for the relay " click "...

The relay should be heard a second or two after power up. This is normal.
 
Don’t approach any of the boards for voltage measurement with normal test leads because sooner or later you’ll short something out and end up with much much bigger problems. Please get some IC clippers or mini grabbers before you start, they’re available in Akihabara or from some online stores (Yodobashi, Amazon, etc.).
 
avionic said:
Listen for the relay " click "...

The relay should be heard a second or two after power up. This is normal.
Click to expand...
Here is the scenario, more or less:

1. My turntable is on, playing. Amp is off.
2. I turn on the amp. No music from the speakers for about 3 seconds, then I hear a click, relay engaged I assume, and music starts loud and clear from the speakers. Meters are working. Output looks right. At this point everything is a-ok. I assumed the click 3 seconds after turning on the amp was the relay going from protect to normal operation.
3. After 2-3 minutes, the music abruptly stops, meters go oos. I don't necessarily hear a click, but with music playing, it may be hard to tell. I need to try this again with volume all the way down.
4. I can repeat this process by turning the amp off and on again.
 
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joshcain said:
Here is the scenario, more or less:

1. My turntable is on, playing. Amp is off.
2. I turn on the amp. No music from the speakers for about 3 seconds, then I hear a click, relay engaged I assume, and music starts loud and clear from the speakers. Meters are working. Output looks right. At this point everything is a-ok. I assumed the click 3 seconds after turning on the amp was the relay going from protect to normal operation.
3. After 2-3 minutes, the music abruptly stops, meters go oos. I don't necessarily hear a click, but with music playing, it may be hard to tell. I need to try this again with volume all the way down.
4. I can repeat this process by turning the amp off and on again.
Click to expand...
OK....... Press on to what I posted in post # 10.. When the audio cuts out.
 
Sparkplug said:
Whatever you do, please do not start carpet changing components hoping the problem will go away. You’ll end up damaging the unit and change its signature sound. The best advice (diagnosis) was given by @avionic above, there’s probably a bad (cold, cracked, etc.) solder joint(s) somewhere that acts up when it gets warmed up. First and foremost, find someone who can reflow all the solder joints in that unit, it’s not as trivial as it sounds, and take it from there. I’d offer to look at it for you but barring occasional pointers, due to heavy work commitments (unrelated) this year, I’m unable to.

Just as an FYI, of all the hundreds of caps I’ve replaced, I’ve never had a single bad or out of spec one in Japan. It must be the weather, so stay away from those overpriced eBay stuff. If anything, re-capping should be one of your last worries after everything else works. I have, however, seen horrendous solder joint conditions that made me wonder how the amps even worked. Cleaning and refurbing the physical aspects of the amp (switches, volumes, solder connections, cables, RCA connector connections, etc.) would be my priority unless of course you know for a fact that a component is bad. Good luck.
Click to expand...
Will do.
Sorry for the slow response on action taken. I'm in Tokyo during the week but spend weekends in Kamakura, which is where my turntable setup is located. I could haul it all back to Tokyo to have more time to work on it during the week, and I may if the project stretches out...
 
joshcain said:
Will do.
Sorry for the slow response on action taken. I'm in Tokyo during the week but spend weekends in Kamakura, which is where my turntable setup is located. I could haul it all back to Tokyo to have more time to work on it during the week, and I may if the project stretches out...
Click to expand...
No problem at all. Kamakura is nice, I go there once in a long while. Keep up the updates, I think your amp will be up and running in no time.
 
Two simple things a guy could do:
1. Squirt some deoxit5 in the coupler switch in back and cycle it a few times (between pre-out/ main ins)
2. Squirt some in the headphone jack in front and insert a jack a few times

I've seen 14 page threads from those simple things.

See how it behaves while listening to headphones
Good luck
 
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Update -
Sorry for the long delay. I had some unplanned remodeling that came up with my house, and it postponed my sound system project. I actually had to break everything down and store it in my upstairs closet while replacing the downstairs flooring, among other work.
Great news. While all of my gear was out of commission, I did a deep dive cleaning the amp and replacing the very old Technics 271c integrated headshell/cartridge with a new Nagaoka cartridge and MP-100 stylus on my turntable. I finally got everything put back together this past weekend and I'm happy to say everything works like a champ. Audio is loud and clear, and every function on the amp works perfectly.
The only thing that is a little funny is the amount of time that the muting delay lasts when I first turn on the CA-1000. Sometimes it lasts 3-5 minutes - and then the relay engages and she works perfect all day long. My understanding is it should be less than that. It's not a scientific observation, but I swear the actual room temperature has an impact. For example, in the winter when my under-insulated old Japanese house is frigid, the muting delay seems to take longer. In the spring when it's nice and warm, the muting delay is much shorter. This leads me to think that components are literally "warming up." It's nearly 50 years old, so maybe it takes a bit longer to warm up? My assessment of the internal components is that they are 100% original and had never been cleaned before I completed that task.
Any thoughts on the extended muting delay and if it should be a concern?
Thanks!
 
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