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View Full Version : Pulled my KayPro 8088 PC-10 out of storage, disaster!



Todd82TA
September 19th, 2014, 05:25 PM
So, long story short, I moved for a job for several years, and put my KayPro in storage during that time. The company that held my household goods stated that the storage was air conditioned, but I'm quite confident that's not the case.

I hooked up my KayPro today thinking I was going to relive my youth, and nothing. I opened it up, and OMG... the entire floor of the computer case was rusted. I thought maybe it flooded, but apparently the battery that was soldered on the motherboard had basically exploded, dumping the internal acid all over the motherboard, and all over the floor of the case.

So I'm kind of bummed, and I'm trying to figure out what I want to do, or if I just want to toss everything. I'm not one to be a pack rat, so I don't like to keep stuff if I don't need it... but I kept this computer around because it was my first and it was indicative of the career I have.

Anyway, for those who know the KayPro PC-10, there is almost nothing on the motherboard. Almost everything sits on full-length cards. The simple motherboard, which is nothing more than a breadboard with nine 8-bit card slots, connections for the power supply, a keyboard BIOS, the battery, and that's basically it. Well, after cleaning it up (it was covered in acid, it looks like the only real damage is where the battery was soldered. I'm not an electrical engineer, so don't laugh, but those hot dog looking things that have different colored strips running perpendicular on them, well... three of those appear to have essentially disintegrated... but the board itself is still good.


I'm really kind of bummed... and I'm not sure if this something (at this point) I want to try to fix or repair.

So I guess I'm both asking for motivation, and second... how the hell do I know what kind of hot dogs I need to re-solder onto the motherboard? I don't have schematics or anying.


On a side note, I also had a Leading Edge 386 SX-16 which, when I just opened it up... same exact thing. The area around the battery has acid all over it. No where near as bad, but it too doesn't turn on anymore. Really frustrated.

SGTSQUID
September 19th, 2014, 06:23 PM
Could you post a picture of the motherboard? I have a Zenith PC backplane that sounds similar. Maybe that could work as a replacement with a little modification.

Todd82TA
September 19th, 2014, 06:47 PM
Could you post a picture of the motherboard? I have a Zenith PC backplane that sounds similar. Maybe that could work as a replacement with a little modification.


Hi, thank you very much! After doing some research, I now know exactly what you mean by backplane, and that is exactly where the damage is.

I have a close-up of the corner of the backplane where the battery bled itself. I am actually shocked at how well it cleaned up, surprisingly, the bread-board seems totally undamaged, but any of the components that were soldered on in that area were totally destroyed. Where you see the red dots that I added, that's where I believe there actually were resistors soldered on. Where you see the two yellow dots is where the single battery was soldered diagonally across the two battery slots.

http://www.PontiacPerformance.net/Temp/8088.jpg

smeezekitty
September 19th, 2014, 08:16 PM
Keep in mind there isn't always components soldered just because it is silkscreened.

the ICs up top look kind of corroded. I would ohm out any suspect traces.

JDallas
September 20th, 2014, 08:22 AM
I concur; there probably were no components in those locations. The silkscreen shows that it was designed for variable configuration of battery sizes and voltage. The resistors, capacitors and diodes there were likely used for certain configurations.

If there was a component that was weakened by the acid and mechanically snapped off, you'd still see the solder holes with a bit of component lead attached from the top and bottom of the board. Battery acid isn't that corrosive. It will usually eat exposed traces, those on your board with a soldermask layer (that glossy green coloration) appear unaffected.

In your photo, there appears to be that rusty color corrosion around the leads of R3 and in some of the neighboring socketed chip pins. The latter is probably more of an issue. WITH POWER TURNED OFF, it might help to re-seat those chips to get a good pin to socket connection.

Normally just rocking the chip in the socket without removing the pins (can cause a bad bend if not careful) would suffice, but you may need to remove the chips and clean the contacts - don't do that unless you're comfortable about inserting chips into sockets... they can rotate on you with a thumb full of bent pins if you're not careful. An chip insertion tool is nice but rare these days.

If you see corrosion on the inside pins of the socket, you can carefully clean the contact surfaces with the sharp point of an x-acto knife (I recommend wearing safety glasses because you don't want a broken tip flying back). If there is a lot of corrosion, use compressed air to blow out bits so it doesn't just pool in the bottom of the socket. Keep your distance when blowing that stuff out.

The chips that are soldered but colored by corrosion are NOT likely to be any problem... that's just superficial corrosion and the soldered chemical process (yes, its not a melting and cooling process, its chemical) will keep a good connection. Sockets and connectors that rely upon contact of two metal surfaces are the most affected because the corrosion is like an insulating paper between two contacts; electrons don't get through, or if marginal, not enough get through.

Generally, if you've not done a lot of restoration or technical work, its best to do as little as necessary. Save getting ambitious on expendable projects. Do the easy stuff first and see check to see if that takes care of the problem. When you accumulate more experience, you can take more ambitious risks.

Stone
September 20th, 2014, 09:23 AM
I thought maybe it flooded, but apparently the battery that was soldered on the motherboard had basically exploded, dumping the internal acid all over the motherboard, and all over the floor of the case.FWIW, there's no acid inside a NiCAD. The electrolyte is KOH which is a strong base.


Battery acid isn't that corrosive. It will usually eat exposed traces, those on your board with a soldermask layer (that glossy green coloration) appear unaffected.Again, battery acid, H2SO4, is in car batteries, not NiCADs. When NiCADs leak the excretion is basic, not acidic.

In summary, a weak acid, e.g., vinegar, aka acetic acid, can be used to clean up after a NiCAD leak.

OTOH, if the leakage were an acid, baking soda, NaHCO3, would work nicely because it is basic.

Chemistry 101 class is dismissed. :-)

Todd82TA
September 20th, 2014, 01:50 PM
I concur; there probably were no components in those locations. The silkscreen shows that it was designed for variable configuration of battery sizes and voltage. The resistors, capacitors and diodes there were likely used for certain configurations.

If there was a component that was weakened by the acid and mechanically snapped off, you'd still see the solder holes with a bit of component lead attached from the top and bottom of the board. Battery acid isn't that corrosive. It will usually eat exposed traces, those on your board with a soldermask layer (that glossy green coloration) appear unaffected.

In your photo, there appears to be that rusty color corrosion around the leads of R3 and in some of the neighboring socketed chip pins. The latter is probably more of an issue. WITH POWER TURNED OFF, it might help to re-seat those chips to get a good pin to socket connection.

Normally just rocking the chip in the socket without removing the pins (can cause a bad bend if not careful) would suffice, but you may need to remove the chips and clean the contacts - don't do that unless you're comfortable about inserting chips into sockets... they can rotate on you with a thumb full of bent pins if you're not careful. An chip insertion tool is nice but rare these days.

If you see corrosion on the inside pins of the socket, you can carefully clean the contact surfaces with the sharp point of an x-acto knife (I recommend wearing safety glasses because you don't want a broken tip flying back). If there is a lot of corrosion, use compressed air to blow out bits so it doesn't just pool in the bottom of the socket. Keep your distance when blowing that stuff out.

The chips that are soldered but colored by corrosion are NOT likely to be any problem... that's just superficial corrosion and the soldered chemical process (yes, its not a melting and cooling process, its chemical) will keep a good connection. Sockets and connectors that rely upon contact of two metal surfaces are the most affected because the corrosion is like an insulating paper between two contacts; electrons don't get through, or if marginal, not enough get through.

Generally, if you've not done a lot of restoration or technical work, its best to do as little as necessary. Save getting ambitious on expendable projects. Do the easy stuff first and see check to see if that takes care of the problem. When you accumulate more experience, you can take more ambitious risks.



Thanks Dallas, I appreciate the response.

So, when looking at the board, C1 and R2 both have open holes where a component might be.

However, CR1, CR2, and R3 all have solder in the holes. There was so much caked on "stuff" that it was hard to even see what was there and what wasn't.

With respect to rust / corrosion, this is what the case looks like under the motherboard:

http://www.pontiacperformance.net/Temp/BIOS_BATTERY.jpg


I was shocked to say the least, I never would have suspected that the tiny motherboard battery could have caused literally so much damage.

Todd82TA
September 20th, 2014, 02:20 PM
I also wanted to add... I think I'm going to just get rid of the Leading Edge. Even though it seems like it has far less damage, I just don't really need it. I'm definitely keeping the Kay Pro. The KayPro has a "s**t-ton" of damage to it, as you can see above, but it was my first, and I am determined to make it work again, or at least use the case for a resto-mod build.


On a side note, would anyone be interested in my Leading Edge? I will give it to you for free, you just pay shipping. I have the ORIGINAL box (in excellent condition), all the manuals, the computer case has no color fading (no browning of the plastic). Everything is there, 386 SX-16 processor, keyboard, three-button Logitech mouse, 5.25" floppy, 3.5" floppy, the St3144a Seagate 130mb hard drive, the 16-bit drive controller, the 512k SVGA graphics card, 4 megs of 60ns SIMS, etc. It comes with GeoWorks 1.0 (special version for the Leading Edge D3/SX), and also Windows 3.11.

If anyone wants it, please let me know... I'll box it all up and ship it to you, just fix it, that'll make me feel better.

Stone
September 20th, 2014, 02:22 PM
I was shocked to say the least, I never would have suspected that the tiny motherboard battery could have caused literally so much damage.It didn't. That rust is not a result of battery leakage.

cbolvin
September 20th, 2014, 02:22 PM
That's not from a battery. You might want to check the power supply if that's what was located on the top right of the photo. Looks like whatever leaked pooled there and ran down to the left and towards the left side of the case.

Todd82TA
September 20th, 2014, 02:51 PM
That's not from a battery. You might want to check the power supply if that's what was located on the top right of the photo. Looks like whatever leaked pooled there and ran down to the left and towards the left side of the case.


Well, I don't know what to tell you, but it did. It was a battery that was soldered in place there, literally had burst out the side and the entire contents had leaked out all over that corner of the motherboard, and then down and around the bottom of the case. The power supply works fine, as I pulled it out and was using it to power a hard drive that I connected to another computer so I could save the data off of it. The battery says it's a lithium, made in Israel.

3pcedev
September 20th, 2014, 03:09 PM
It didn't. That rust is not a result of battery leakage.

I agree, that looks more like water damage. Those NiCad's only hold about 10mL of electrolyte; nowhere near enough to cause that kind of damage to the case. I would say it is far more likely that water got onto into the PC; corroded around the battery (which caused it to leak) and then made its way under the motherboard causing the case damage. Furthermore the water will dilute the contents of the leaking battery exacerbating the problem.

Edit - Just noticed you mentioned it was a Lithium battery. Lithium batteries form lithium hydroxide when they leak which is basic and also unlikely to cause that extent of damage alone.

Todd82TA
September 20th, 2014, 03:20 PM
I agree, that looks more like water damage. Those NiCad's only hold about 10mL of electrolyte; nowhere near enough to cause that kind of damage to the case. I would say it is far more likely that water got onto into the PC; corroded around the battery (which caused it to leak) and then made its way under the motherboard causing the case damage. Furthermore the water will dilute the contents of the leaking battery exacerbating the problem.

Edit - Just noticed you mentioned it was a Lithium battery. Lithium batteries form lithium hydroxide when they leak which is basic and also unlikely to cause that extent of damage alone.


I really don't know what to say, but no water got into the computer. The box has no water spots, and it's never been around water. Same with the Leading Edge, but the Leading Edge had a lot of blue "fuzz" around the contacts that it affected. Nothing else in the computer looks like that, and all... literally ALL of the fluid comes from that one corner of the motherboard (which is essentially dead-center in the case at the leading edge of the middle MB support bar)

EDIT: It was in South Florida, and may have been exposed to humidity and heat... don't know if that makes a difference, but that's what I was saying in the first post. It is near 100% humidity here in South Florida all the time during the Summer.

SGTSQUID
September 20th, 2014, 03:23 PM
From the picture you posted, that looks like a little more than a passive backplane. The Zenith one that I have just has 8 slots and a few passive components with no IC's. It probably won't work as a replacement.

Todd82TA
September 20th, 2014, 03:50 PM
From the picture you posted, that looks like a little more than a passive backplane. The Zenith one that I have just has 8 slots and a few passive components with no IC's. It probably won't work as a replacement.

Ok, well... thank you very much for looking anyway, it was worth a shot. I'm determined to at least fix the KayPro...

Stone
September 20th, 2014, 03:58 PM
I really don't know what to say, but no water got into the computer.


It was in South Florida, and may have been exposed to humidity and heat... don't know if that makes a difference, but that's what I was saying in the first post. It is near 100% humidity here in South Florida all the time during the Summer.Those two statements are in direct contradiction with each other. :-) Humidity *IS* water. The humidity in Florida is devastating and could easily be the sole reason for all that rust.

3pcedev
September 20th, 2014, 04:26 PM
Can you post up more detailed pictures of the entire motherboard? Based solely on your last photo it looks like 2 IC's will need to be replaced (and perhaps those resistors you mentioned; if they were indeed populated). I'm interested on the overall condition of the rest of the board (front and back sides).

Todd82TA
September 20th, 2014, 04:44 PM
Can you post up more detailed pictures of the entire motherboard? Based solely on your last photo it looks like 2 IC's will need to be replaced (and perhaps those resistors you mentioned; if they were indeed populated). I'm interested on the overall condition of the rest of the board (front and back sides).


Thank you, will do... I'll try to use one of my other cameras so I can manually focus. When you say replaced... the chips themselves I think look ok... but I'm hardly one to make that judgment I guess. I'll remove the keyboard bios and then take some pictures of the pins.

3pcedev
September 20th, 2014, 05:22 PM
The problem with the IC's is that the moisture / corrosive chemicals from the battery get between the plastic case and the IC pins. Overall they might look like the legs are a bit green but ok otherwise; however in reality the corrosion in also inside the plastic case which has then damaged the IC itself.

I have a 5160 motherboard that had a battery leak. Once it was cleaned it looked brand new (except for some greening of the IC pins). I replaced about 8 IC's on the board and still it had errors. Luckily your board has a minimal IC count so it should be easier to repair.

JDallas
September 20th, 2014, 06:45 PM
The recent photo shows rust damage significant enough to be caused by water. The pattern of rust both indicates the orientation of the computer in storage and suggests a possible entry point.

It looks to me like some water flowed in from the center back baseline. Someone mopping the floor? A roof leak? Maybe even a just the splashed droplets hitting the shelf or floor behind the stored computer?

Personally I think the splashed continuous drops from a roof leak sounds more probable. The drops would have splashed up along the back wall of the case, slid down to the base and entered there, splashes entering the fan hole in the power supply flowing underneath it and rusting that small intense rust patch there, and some of the sliding droplets coming inside around a connector and showing the highest rust mark on the center back wall.

A roof leak would have repeated this scenario many times before a roof repair might have stopped it. Plenty of time for that level of damage to occur.

That's all interesting speculation but really its moot. You have rust... you clean rust away.

As Mr. Miyagi said in the movie, Karate Kid, "Rust On... Rust Off"

Krille
September 21st, 2014, 02:13 PM
Guys, the amount of rust is not a mystery. Read the Wikipedia article on Hygroscopy, especially the part about Deliquescence (http://en.wikipedia.org/wiki/Hygroscopy#Deliquescence). Basically, what happens is that the chemicals in the battery absorbs so much water from the air that they dissolve in it. You then get a very corrosive liquid that runs freely to where ever gravity pulls it.