Lifespan depends on temp. But if the materials used in the capacitor were bad to start with their life will be reduced. Everything is built to a cost and a DIYer replacing parts will generally use a much better part than the manufacturer will.
The Ford Fiesta from the 90s didn’t come with an intermittent wiper mode, that’s an extreme example of a small cost saving made by a manufacturer that an individual would not make.
I’d imagine manufacturers don’t bother to plan for a 25+ year lifespan of electronics now either.
Temperature damage dries out electrolytic caps, so most likely these go off with a bang and funny smoke. In 90% these are caps involved in power transformers or PSUs. Leakage mostly comes due to chemical reactions by reduction and electron migration of the electrolytes…and could be prevented by solid state caps.
All comes by cost reduction, as drying could be prevented by enough space on the PCB…a good example for that is the Behringer ADA8000. Chemical issues have mostly the cause that they are extremely cheapo stuff or plagiates.
Alright thanks a lot guys, I double checked all the other caps, they all seem fine.
So I guess, the bad capacitors were just the one from the same batch (labeled part number on the service manual: V4143000). They are labeled on the top “L2P”.
I noticed that on other units (pictures that I found online), these caps are labeled otherwise A1P. So if you have all these 47uf caps labeled “L2P”, consider replacing them.
I’m writing this for reference if somebody ever have the same trouble with their RS7000.
For now, the unit is back to it’s owner, ready to be furthermore tested and live proofed for the upcoming gig.
Again, I would like to thank everyone for their input, help and precious advices. It feels so good reviving gear, especially when you can have such great advices from this community.
@Paulus – congrats on the successful repair!
If you have suspicious elco caps, don’t just blindly replace them since you’re not supposed to fix what’s not broken. Instead, get yourself a decent LCR meter and test those caps in circuit. By this time all problematic elcos ESR degraded enough to be very noticeable.
I’m using DER EE DE-5000 High Accuracy Handheld LCR Meter w/ TL-21 TL-22 & TL-23 from ebay – it’s reasonably priced and never let me down.
I have a Yamaha RS7000 for a few years and recently encounter exactly the same problem : the unit won’t start because two of these 47uf 16v caps have gone themselves (!, and a third one with the help of my finger…). On my unit, these caps are labeled “G2P”, a serie not far from yours …
So, I am starting replacing them.
@Paulus : I reed that you repaired it :
- did you finally found new SMD caps or replace them by thru hole caps ?
- I found replacement parts in SMD, is it difficult to sold without a special SMD iron solder (never try) ? Maybe, recommandations ?
- I see your pictures of the bigger 470uf 10V SMD caps, mines have exactly the same “deformation”, it looks ok for me.
Thank you in advance for your responses .
Finally excuse my band english, I am french. ; )
First of all, it is good that this thread is any help to somebody else.
I managed to repair the unit and make it work by soldering thru hole caps. I am personally not equipped to solder SMD components (and I have yet never tried it anyway).
I replaced all of the nine 47uf 16v caps (all located on regulator circuits for the ICS), only 6 had leaking marks under it, but as I removed the three remaining, I noticed they also started leaking underneath.
I would say that it would be better to replace them with SMD caps, it will hold better on the board, but I was personally a bit in a hurry. nevertheless, I fastened some of the wonky thru hole caps with hote glue to be sure the connection would hold. The problem I encountered was that the leaking damaged the coper traces and therefore, the solder was not holding very well on the board.
Concerning the 470uf SMD caps, they were fine, the deformation is normal I guess.
Before you attempt anything, be sure to read the schematics and informations in the service manual carefully to be more familiar with the board you are going to work on.
If you need further advices, do not hesitate to PM me, I am French too, so it might be quicker.
Keep us posted on your repair!
Thank you all who contributed to this thread. Without it I would never have found the issue.
My RS7K would not boot and this is the first bit of info I found. Unfortunately I was unsuccessful in rescuing the main board to my original RS7K - I believe there is something else wrong. I eventually obtained a second RS7K and swapped its main board into my old RS7K. The new board also showed signs of corrosion which you can see in the photos below. After removing all 9 caps, removing the old solder, cleaning the corrosion and replacing with radial thru-hole caps, all is working perfectly. The replacement board is in my old RS because the knobs are in great working condition and last year I had replaced all the key tactile switches with ones that felt more ‘clicky’, less spongy for my taste.
Happy to have my RS back to life!
Here are the caps I replaced: