Motherboards with swollen and leaking electrolytics

FredC · Aug 14, 2020

Did a hard drive replacement for a fellow machinist who uses a desktop to drive a small CNC mill. One of the IDE ports was bad made me think I did not hold my mouth right and did the static thing to it. After I got the replacement hard drive in and seemingly everything working i decided to look the mother board over and Yikes! more than half of the eletrolytics are swollen and leaking. Can you still get older style motherboards with 500 mhz processors?
I thought I would be smart 20 years ago bought a couple of brand new boards and processors. They are still in the boxes and I checked them this morning and both have several swollen caps also. If you can not get new boards in this class with IDE hard drive capable is there someone reliable that can replace these caps?
I am spooked now and will be checking all the machines for this condition.

crossthread · Aug 14, 2020

We were replacing motherboards by the dozens that had bad caps from Taiwan a few years back. These were IBM boards. For a while IBM was covering the cost but they stopped doing that after a while. You may be able to get some help from the manufacturer since these bad caps were used in a lot of different boards. The "pie" shaped segments on the top of the cap would split and swell and brown goo would leak out. You should be able to replace them yourself.

MattiJ · Aug 14, 2020

Not rocket science to replace the caps but it needs some experience and equipment. Local "TV repair shop" should be able to help. Even if they are mostly gone like dinosaurs you should be able to find one locally. 30-50 bucks might be reasonable price depending on how exotic the components are.

New motherboard selection is probably very short list or non-existing. Ebay/graigslist for used ones.
You can add IDE port to any modern mobo with PCIe adapter as long as the OS supports both the mobo chipset and IDE card.
For example something like this https://www.idealo.de/preisvergleich/OffersOfProduct/4643713_-pcie-ide-pex2ide-startech.html

Guest · Aug 14, 2020

When I was keeping PC driven old CNC Mills alive I used this place, but that was 15 years ago. I had machines that ran on DOS.

Alltech-OSA – For All Your Computer's Needs

Hardplates · Aug 14, 2020

Super easy job if you buy a desoldering machine. Without one it is a total pain in the ass and the chances of lifting a trace are pretty good.

Scottl · Aug 14, 2020

If the cost of hiring someone to replace them is exorbitant or you can't find someone it is possible to do it yourself.

You will need vacuum desoldering equipment and an iron, plus a good electronics solder.

A minimum would be a Soldapult (desoldering pump) and a 30 watt iron. Most people misuse a Soldapult, which is a simple device with a spring-loaded plunger. They must be cleaned often and the O-ring should be greased with silicone grease every time it is opened for cleaning.

Equipment with built-in vacuum is better but will run $250 plus. In any case you want to practice on junk PCB boards before doing it on your precious mother boards.

For solder I recommend Kester or Multicore 63/37 with activated rosin (RMA) core. Use isopropyl alcohol to remove flux residue.

Dan from Oakland · Aug 14, 2020

There are a few folks on eBAY that offer recapping services and its pretty reasonable. I had a mother board recapped a few years ago and the cost was around $100.00 I checked recently and contacted one fellow about doing another one.

jz79 · Aug 14, 2020

I'd suggest avoiding trying to use spring actuated desoldering pumps, they work OK for single sided pcbs, but motherboards have voltage supply and ground planes in between the layers you see from top/bottom sides, those layers are huge copper heat sinks basically, they soak up heat and a 30W soldering iron won't be able to put enough heat in quickly enough to do this, you could wiggle a cap out with it, but it will take a long time to put enough heat into the joint... and you shouldn't hold a 330-350C hot iron on the soldering pad for more than 3-4 seconds - that is the reason why traces and pads lift - the epoxy holding it down burns up

desoldering station, even 100$ ones from far east fleebay work extremely well for this, and if you do it right, the cap will almost fall out by itself, leaving a nice clean hole to insert the new cap in, it is basically a sub minute operation per cap

having learned soldering from about the age of 5 (son of an electronics engineer...), I'd rate cap replacement in motherboards with a desoldering station as very easy task, even for a complete novice, and you can use the same soldering gun to solder the new cap in too - but using the spring loaded plunger pump - extremely difficult to do it well and not ruin the board

crossthread · Aug 14, 2020

I hope I don't get "flamed" for this but I have to disagree on a vacuum de-soldering setup. In a former life I did a lot of bench work repairing circuit boards on high speed paper converting machines. We had some of those vacuum units but I found that they have a tendency to splatter solder in places where you don't want it to go. I will say that these were the hand held devices that you cock and then release with a push button to suck up the solder. I'm sure there are more expensive units that probably work better. I found the very best way to de-solder is with solder wick. It comes in a roll of different gauges for the class of work you are doing. It is cheap and works very well. I was able to un-solder 64 pin flat pack ICs very easily using the wick. This was just my preference and I am only trying to offer an alternative to vacuum systems that is dirt cheap and from my experience, very effective.

Scottl · Aug 14, 2020

Yes 100% agree about solder pump. I only suggested it if the OP was very cost sensitive. Since I bought a Hakko desoldering pistol I haven't touched one. They now sit in a drawer with the squeeze bulb electric ones, including one I converted years ago to work with a compressed air vacuum siphon.

Crossthread,

In my experience solder splattering with a plunger unit was a result of cleaning too seldom. A decent ($250 or so) vacuum pistol with the pump near the catch bottle (like my Hakko 808) is faster and less risk of overheating.

Again, whether spring plunger, squeeze bulb or controlled vacuum frequent cleaning is important to proper operation. I hated the new Pace outfits from the moment I saw them because you throw away the paper tube. I used to keep several cleaned glass tubes with filters on hand for a quick swap-out. One of the great feature of the Hakko is the spring-loaded tube. It takes only a couple seconds to remove the tube, tap excess solder into a dish, and replace the tube, Filters last a long time if that is doen frequently.

Hardplates · Aug 14, 2020

Todays electronic fun fact.

If the first shot doesn't work you need to add solder. It relies on surface tension to suck the deep stuff out so you can't desolder a small amount without adding some. The fresh solder and flux also helps clean it.

As far as the spring loaded jobbies, either throw them out or give them to someone you don't like.

The el cheapo desoldering stations seem to work damn near as well as my Hako

jz79 · Aug 14, 2020

wick will never work for motherboards

vacuum desoldering station is not the same thing as those hand held pumps, I thought I explained it clearly enough, you can forget about those and 30W soldering irons, not enough vacuum with that spring loaded pump and not enough heat in the tip of a typical 30W iron, desoldering station with electric vacuum pump and a tubular tip that goes over the leg is the only way here, and you won't spatter anything, all the solder goes into the gun...

doug8cat · Aug 14, 2020

I do a lot of recapping from amps to power supplies. Have all the proper equipment and replace with (i.e Rubicon etc.) top quality caps.
Just FYI capacitors don't usually fluid, leaky as it refers to becoming electrically not fluid.
If you are interested PM me. We are SLOW where I work so could turn it around pretty quick.

Regards,
Doug

Terry Keeley · Aug 14, 2020

I like a wick (and flux) to de-solder and remove the caps, replace with new ones respecting the polarity. If you use a pump type sucker watch the "droppings", you can clean the board with alcohol and a soft brush to be sure nothing is left behind.

Easy peasy.

Badcaps.net Forums - Recapping Overview

Conrad Hoffman · Aug 14, 2020

Multilayer motherboards can be a nightmare unless you have the right equipment. I've done it with a Soldapullt DS017, but can't recommend it. You also need to be sure you buy suitable caps, which may be low esr caps designed for switching applications. Or not, depending on where they are. Given how cheap new motherboards are, I'd figure out how to upgrade the system if at all possible.

FredC · Aug 14, 2020

So the consensus is that is easy and difficult to do your self. My one attempt to resolder a keyboard connector did not go well. I heard the reason was multi layers. Between my friend and I we have three Dynamechtronic 2800s running AHHA software. Pretty solid system for small parts. They work good with 500 MHZ boards, not sure if today's super fast boards will work. The plug in cards may not find a home on new boards either.
I responded to one of the links and will send a PM to Doug.
Thanks for all the replies.

crossthread · Aug 14, 2020

jz79 is correct when it comes to 30 watt irons. Some folks will tell you to use an iron of low wattage to keep things from getting too hot. This is completely ass backwards. You want a really hot iron so you can get in and get out in a hurry. A low wattage iron will cook components and de-laminate the traces.

Hardplates · Aug 14, 2020

crossthread said:
jz79 is correct when it comes to 30 watt irons. Some folks will tell you to use an iron of low wattage to keep things from getting too hot. This is completely ass backwards. You want a really hot iron so you can get in and get out in a hurry. A low wattage iron will cook components and de-laminate the traces.

Absolutely correct, this applies to just about everything not just soldering. In and out before the heat has a chance to propagate through the material.

gustafson · Aug 14, 2020

Scottl said:
If the cost of hiring someone to replace them is exorbitant or you can't find someone it is possible to do it yourself.

You will need vacuum desoldering equipment and an iron, plus a good electronics solder.

A minimum would be a Soldapult (desoldering pump) and a 30 watt iron. Most people misuse a Soldapult, which is a simple device with a spring-loaded plunger. They must be cleaned often and the O-ring should be greased with silicone grease every time it is opened for cleaning.

Equipment with built-in vacuum is better but will run $250 plus. In any case you want to practice on junk PCB boards before doing it on your precious mother boards.

For solder I recommend Kester or Multicore 63/37 with activated rosin (RMA) core. Use isopropyl alcohol to remove flux residue.

Let's just quote Scott so it doesn't get lost, good advice there

Soldapullit is a reworkers best friend.

If you were just doing one cap for instance, cut the cap apart so you have access to both sides of the feedthrough, grab the lead from the component side and heat it from the etch side. Rotate and gently pull without massively overheating and you just may end up with the lead out and a clearish hole
If your new cap won't get through the hole, warm it up and push the new cap lead in.

I would think most electrolytics would be on larger traces, but if you do rip an etch, it is not the end of the world, a piece of 26 ga is a valid replacement, either clean and tin the last spot that is still adhered, or chase it back to its source and solder to the lead

A good regulated iron is an excellent investment, I had an old Weller, but it died, and I have a Radio Shack one that is not as nice but works. Buy spare tips of the right size for different jobs

MattiJ · Aug 14, 2020

jz79 said:
wick will never work for motherboards

vacuum desoldering station is not the same thing as those hand held pumps, I thought I explained it clearly enough, you can forget about those and 30W soldering irons, not enough vacuum with that spring loaded pump and not enough heat in the tip of a typical 30W iron, desoldering station with electric vacuum pump and a tubular tip that goes over the leg is the only way here, and you won't spatter anything, all the solder goes into the gun...

Even a decent desoldering iron like Hakko 471 struggles with some motherboards and especially industrial/telecom heavy duty power supplies. I have some scrapped cellular base station power supplies that would need oxyacetylene torch to desolder! (Thick 2.4mm boards with heavy copper, high current groundplane and powerplane layer after layer)

With extremely stubborn cases good preheat, applying plenty of fresh solder and using iron+desoldering iron simultaneously does the trick most of the time.

Motherboards with swollen and leaking electrolytics

Diamond

Titanium

Titanium

Guest

Guest

Stainless

Diamond

Titanium

Stainless

Titanium

Diamond

Stainless

Stainless

Titanium

Titanium

Diamond

Diamond

Titanium

Stainless

Diamond

Titanium

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