IIci with Maxell bomb damage

[Fizzbinn]

Bought a IIci setup (including AppleColor High Resolution RGB Monitor, Extended Keyboard II, mouse, and all cables) off Craigslist for $50. Woo-hoo.  :ii:  

I wonder what will be inside! (Foreshadowing), maybe a DayStar ’040!

Posting said it wouldn’t boot but figured it could be another recap project. Got it home powered it up, no sound (thats just the expected bad caps) screen came on but no mouse shows up, no blinking floppy icon. The screen looks odd though, the image has square corners. I need to figure out what’s that means...

Okay, open it up, take it apart (should have done this first..), drive cage is a bit stuck, and then underneath, my first encounter with the dreaded exploded Maxell PRAM battery!  ><

By the looks of it this happened a while back, on the surface I though this might look worse, everything just looks dirty... any thoughts on how to begin? First clean with isopropyl alcohol? Baking soda or something to neutralize the dried battery acid? Anyone have experience to tell me how bad this is?

 

[maceffects]

I hate seeing Macs like this suffer from Maxell.  The good news is that its nowhere near as bad as I've seen.  This really looks fixable at least from this distance. 

 

[blusnowkitty]

It sure looks like you're going to need a new clock crystal. Anyone know what the value is? 

 

[BadGoldEagle]

First I‘d try to remove what’s left of the crystal. There should be a couple of solder joints on the back side (if they’re not corroded to hell that is). Then get some white vinegar and scrub with an old toothbrush until you can’t see any of the brown stuff. Be careful of the RTC chip, you probably won’t find a replacement if you accidentally damage it. Rinse with clear water or isopropanol. If you choose water, dry it up with a hair dryer afterwards. 
 

There might be a broken trace under the crystal... but again this has to be one of the least damaged Maxell victims I’ve seen. You got lucky.

 

[Fizzbinn]

It sure looks like you're going to need a new clock crystal. Anyone know what the value is?

50 MHz, I actually have some replacements and sockets that I got to overclock a IIsi. I’m not sure the socket would be useful for overclocking here (quick google says it won’t be) but I’d hate to have to desolder again if the replacement clock crystal turned to be bad. Getting the one out on the IIsi was not fun, the pin that must have been on the ground plane was super hard to get hot enough. 

 

[Fizzbinn]

I hate seeing Macs like this suffer from Maxell.  The good news is that its nowhere near as bad as I've seen.  This really looks fixable at least from this distance. 

Fingers crossed! The floppy looks highly questionable though, I guess it might just be surface deep...



Now, which one of these could be responsible


 

 

[Fizzbinn]

This leaky capacitor damage looks like it might the most challenging to fix (for me), the IC popped right off when I touched it with a q-tip.

 
 

the “legs” seem okay



Just when I was getting comfortable with soldering capacitors...  anyone got any pointers?

 

[blusnowkitty]

Just when I was getting comfortable with soldering capacitors...  anyone got any pointers?

Are the pads on the board okay? Pretty much your only option to do SMT packages like that is to get an iron with a very fine cone tip, or invest in a hot air rework station. 

 

[Bolle]

Look up drag soldering. No need for a fine tip or a fancy iron. You can do this with any iron that you can do a recap with.

Not saying a good tip and iron won’t help though  More than that a good amount of flux is they key to get those things soldered down properly.