Best Quality Capacitors made

G

German Muscle

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Aug 2, 2005
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This is for a non PC project.
Im looking for some super high quality caps. Im really getting tired of the caps popping and then sending the ECU off to have the caps replaced and board cleaned. I would like to put an end to this once and for all.
caps.jpg
 
Solid capacitors seem to be better than their regular electrolytic counterparts
 
Which caps are popping? The electrolytics? If they're popping, then chances are they're being subjected to conditions well beyond their ratings. I would certainly look for something with more than 105degC tolerance if ECU stands for Engine Control Unit--it gets pretty toasty under the hood. And car electrical systems are notoriously noisy and outright hostile to anything electronic.

Badcaps has a good description on their front page of good brands and lines to use when replacing caps.
 
Mohonri said:
Which caps are popping? The electrolytics? If they're popping, then chances are they're being subjected to conditions well beyond their ratings. I would certainly look for something with more than 105degC tolerance if ECU stands for Engine Control Unit--it gets pretty toasty under the hood. And car electrical systems are notoriously noisy and outright hostile to anything electronic.

Badcaps has a good description on their front page of good brands and lines to use when replacing caps.
Click to expand...

the ones stamped K on top. These ECUs are notorious for doing this but they are in cab ECUs. You would think professionals that are replacing these for people and cleaning the boards would use something of very high quality.

I have 2 of these computers like this. Might have another one. They cost around 500 dollars each and they are for a 17-20 year old car.
 
I would check the voltage rating on the caps. If they're only rated for 16V, then I'd suspect that voltage spikes (due to the ignition) are making them flake out earlier than they should. My next suspect would be some of the other power-conditioning components--I'm guessing that those larger ICs mounted on the heatsink are regulators or rectifiers, and one or more of them could be going flaky, causing the caps to fail early.
 
Mohonri said:
I would check the voltage rating on the caps. If they're only rated for 16V, then I'd suspect that voltage spikes (due to the ignition) are making them flake out earlier than they should. My next suspect would be some of the other power-conditioning components--I'm guessing that those larger ICs mounted on the heatsink are regulators or rectifiers, and one or more of them could be going flaky, causing the caps to fail early.
Click to expand...
I dont think its voltage related. If it was a power conditioning issue this would be happening.
If the caps leak bad enough it will wipe out the voltage regulation circuit and do this as well.
overvoltage-01.jpg


Chibo said:
What kind of car?
Click to expand...

1991 Plymouth Laser RS Turbo (Same as a Mitsubishi Eclipse and Eagle Talon)


Is there any reason someone shouldnt put solid state caps in something like this?
 
Solids should work, but I believe that like tantalum caps they don't like voltage spikes (say charging goes out of control).


I have a 92 Stealth that had shitty caps in ECU and TCU, I replaced the TCU, but put in some higher quality Sanyo 105* caps. I don't drive the car that much so can't tell how it would be holding up under "normal" use.

What kind of caps have they been installing for it to fail more than once? Sure they didn't just give you another non-repaired ECU?
 
RogueTrip said:
Solids should work, but I believe that like tantalum caps they don't like voltage spikes (say charging goes out of control).


I have a 92 Stealth that had shitty caps in ECU and TCU, I replaced the TCU, but put in some higher quality Sanyo 105* caps. I don't drive the car that much so can't tell how it would be holding up under "normal" use.

What kind of caps have they been installing for it to fail more than once? Sure they didn't just give you another non-repaired ECU?
Click to expand...

The ECU has its own Voltage regulation circuit as well. If the Caps leak it can take it out and bubble the chips.

The board i posted a picture of is one of my actual ECUs. As you can see the ECU is refurbished or not very old. Ive been told its been rebuilt/recapped. The board is really nice and new looking other then where the caps leaked. My guess is shitty caps are being put in. Just standard replacements. If it were me doing this i would be putting the best thing i can find in them.

If i can find some solid state caps or anything better i will buy some and request they put these in rather than the other ones.
 
Yea, it will be some number followed by uF, or you can take pictures of all the printing on them
 
going from the 1st picture i posted this is what they are.
Top Black-47uF
Middle Blue-22uF
Bottom Black-100uF
 
German Muscle said:
going from the 1st picture i posted this is what they are.
Top Black-47uF
Middle Blue-22uF
Bottom Black-100uF
Click to expand...

cap size difference suggests different voltage ratings, what are they rated at, ill see what i can find.

your capacitor requirements are a little high for polypropylene capacitors, they get very large rather fast maybe i can spot some very high temperature electrolytic but all i typically see is 105C

you can try getting capacitors slightly higher voltage rating then currently in there, they will be physically larger caps tho, and for the heat issue, where is this thing mounted, in the dashboard?
 
http://cgi.ebay.com/3-Rubycon-RX30-...189?pt=LH_DefaultDomain_0&hash=item439b5d6d7d
http://cgi.ebay.com/4-Rubycon-RX30-...337?pt=LH_DefaultDomain_0&hash=item439b5d6259
http://cgi.ebay.com/4-Rubycon-RX30-...582?pt=LH_DefaultDomain_0&hash=item45f48b655e

50 volt rating is surely more then you need, aparently that seller is the only guy on ebay selling the high temp variety, Rubycon is one of the best capacitor makers around, if not literally the best

may be a tight fit, with exact voltage ratings i might be able to link you to smaller size capacitors


in other news, with those listings you will have some extras, if it happens again i would question the rest of the circuit

only really looks like the 100uF is blowing on you, doesnt hurt to replace them all... 100uF sounds to me like a power input filter, your car could be doing killer surges on its 12~15v supply, literally, some extra voltage handling probably wouldn't hurt?
 
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Top black says 105C
middle purple says 85C
Bottom black says 105C

These all also say Rubycon. Its mounted in cab down in the center console. There is a place where the carpet pulls up in the passenger side where your feet sit to access it. I leave mine hanging out on the passenger side under 2 floormats because ive been having them go wonky on me. I rarely have passengers so its been no big deal

Keep in mind this isnt an isolated issue. Its fairly common. It happens on my 90-94 model year cars frequently and on a rare occasion the 95-98 cars. Also the 3000GTs have this happen on occasion.
Here is a brief wiki on it.
http://www.ecmtuning.com/wiki/ecurepairhome
 
they shouldnt be getting hot enough to blow in your cab, perhaps giving higher voltage rating caps a shot is worth the time. you still didnt tell me rated voltages, you gave me temperature ratings.

the fact that the middle capacitor didnt leak with a 85C rating suggests to me that your initial evaluation for temperature being the cause is incorrect?
 
German Muscle said:
Top black says 105C
middle purple says 85C
Bottom black says 105C

These all also say Rubycon. Its mounted in cab down in the center console. There is a place where the carpet pulls up in the passenger side where your feet sit to access it. I leave mine hanging out on the passenger side under 2 floormats because ive been having them go wonky on me. I rarely have passengers so its been no big deal

Keep in mind this isnt an isolated issue. Its fairly common. It happens on my 90-94 model year cars frequently and on a rare occasion the 95-98 cars. Also the 3000GTs have this happen on occasion.
Here is a brief wiki on it.
http://www.ecmtuning.com/wiki/ecurepairhome
Click to expand...

Are you running DSM link? I have a 91 eclipse gst
 
ryuji said:
they shouldnt be getting hot enough to blow in your cab, perhaps giving higher voltage rating caps a shot is worth the time. you still didnt tell me rated voltages, you gave me temperature ratings.

the fact that the middle capacitor didnt leak with a 85C rating suggests to me that your initial evaluation for temperature being the cause is incorrect?
Click to expand...
I dont think its temp related. I cant see the voltages. Its cut off on some of them and the others i would have to break off.
mannyman said:
Are you running DSM link? I have a 91 eclipse gst
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Yes i am.
 
Rubycons are very good, unless they're fakes (more common than you may think). I also like the Panasonic FC series or the Sanyo OSCONs (solid caps), both available at Digikey or Mouser for reasonable prices. Black Gate are the highest quality you can get, but are thrillingly expensive. Go with 105 degree ratings and the highest voltages you can physically fit onboard. It sounds like a better power filter design might be in order.

Also, a tip I got from an old TV serviceman - don't mount caps flush with the PCB. The thermal expansion and contraction pull on the leads and eventually tears them out internally. Instead mount them about a mm above the PCB, optionally with a piece of foam sticky tape underneath to hold them while still providing cushion
 
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