Classic repair

[notcrazy_iminsane]

I got my hands on a working Macintosh Classic It starts up and runs just fine, the only problem being that there's no sound. Everywhere I looked says that the Macintosh Classic has built in sound, but nothing seems to work. I opened it up and took out the board and found that nearly all of the capacitors have leaked onto the board. I have no experience replacing them... But is it possible to temporarily fix the problem by cleaning the mess the capacitors left? If so, how would I go about doing that? :O

 

[beachycove]

You almost certainly will not get sound after cleaning without actual repair of the components in question, but the convention is to stick it in an empty dishwasher and run without soap, or else just give it a good long soak in a pan followed by plenty of rinsing. And then dry thoroughly, ideally over several days.

Others will tell you to use isopropyl alcohol or other chemicals. Methinks this is going considerably over the top. Washing with water was part of the original manufacturing process and so is not an especially risky procedure so long as you are not planning to drop a plugged in toaster into the water with it.

The board will need to be washed somehow even with capacitor replacing, as the capacitor goop is the cause of multiple problems.

 

[FlyingToaster]

I don't remember if it does or not but doesn't it have a headphone jack? does that work? I'm getting a Classic 2MB 40SC HD in the mail soon, never changed capacitors before in my life but I'm gonna attempt it with this one since it was only $15!

 

[beachycove]

On re-reading — of course it had sound circuitry.

Turn up the volume to the max. in the relevant System Control Panel and you might get to hear something faint, but the caps will need replacing.

 

[protocol7]

So it's safe to use tapwater to clean the board? I'll be opening my Classic II in the next day or so and expect to see some kind of leakage.

 

[beachycove]

Scrub-a-dub-dub, though I am not sure about that soap or how its use can be reconciled with use of distilled water....

I myself have used ordinary tapwater with no ill effects whatsoever.

 

[notcrazy_iminsane]

I opened up the Classic and cleaned the board with both alcohol and then water with a q-tip. I got sound working out of the headphone jack, but nothing out of an internal speaker yet. I watched some videos on youtube on how to replace capacitors. I'm feeling a little confident on trying to replace them myself after I get a soldering gun and some practice on a junk board.

I'm gonna give the board a good soak when I get home since I couldn't get all the gunk off.

Before I cleaned the board I noticed the floppy drive doesn't work :-/ I wanted to try and figure out how to copy the After Dark files and move them to my 580 for safe keeping while I did a clean install of System 6. Now I gotta figure out how to either fix it or replace it...

 

[protocol7]

Before I cleaned the board I noticed the floppy drive doesn't work :-/ I wanted to try and figure out how to copy the After Dark files and move them to my 580 for safe keeping while I did a clean install of System 6. Now I gotta figure out how to either fix it or replace it...

You can connect the Classic to the 580 with a printer cable and copy the files over Appleshare.

And if you wanted to back up the complete hard disk (it'll take a while over localtalk), you could boot into the system on the ROM (cmd+opt+o+x) and use DiskCopy to make a disk image of your hard disk (create image from folder). Then you have a complete backup of your system (and if you make it read/write and uncompressed you can even boot this in emulators). You need to boot into another system to avoid problems copying files in use.

Once you have everything backed up you can then install a fresh system over the localtalk connection.

 

[notcrazy_iminsane]

I never would've thought of that I'll see if I can find a long enough printer cable to connect the 580 and the Classic.

 

[notcrazy_iminsane]

I found a cable and linked the two together when I got home, however the 580 and Classic don't seem to get along very fine. If I start up with the two linked together, the 580 stops loading after about 3/10 of the OS loads (right before it shows any icons at the bottom). The Classic will either stay on a grey screen with a cursor or go straight to a sad mac with the code 0000000F 00000002. If I try connecting the two any time after they both start up, the 580 will be just fine, but the Classic will lock up, especially after AppleTalk is turned on with the 580.

How do i get this working? xx(

 

[protocol7]

Hmm I've used this a few times (Classic II to 7500 and LC III to 5400) and never had to troubleshoot. It's always just worked. Are you connecting them via the printer port? Is the cable known to be good? It's generally not a good idea to connect anything to ADB when the machine is on however. Always a danger of frying something. So I'm assuming that also holds true for serial.

I just picked the 580 as you mentioned it but you can use any of your Macs with a serial connection as the host. Maybe try setting the 580 AppleTalk connection to Printer port first and then shut it down, hook it up to the Classic and try again.

 

[notcrazy_iminsane]

I know the cables are good. I turned AppleTalk on via printer port through the 580. I'm gonna connect the two, turn them on, and see what happens

EDIT

Just connected the two and turned them on at the same time. The 580 stopped during the OS boot and the Classic's showing the ? over a floppy. Gonna try starting up the 580 then the Classic, then the Classic then the 580.

EDIT EDIT

If I start up the Classic after the 580 boots, it just goes to Sad Mac 0000000F 00000002. I think they keep trying to boot off of eachother's hard drives or something xx( I'm about to try this with the 575 or Power Mac 5500.

 

[notcrazy_iminsane]

I got them both on and connected without crashing once. The only problem is that in the Chooser there's no File Servers. How do I create one on the 580? xx( I'm going crazy from this.

 

[notcrazy_iminsane]

I tested a connection with the Classic on all of my Macs with a serial port on it.

580:

Classic Sadmacs with code 0000000F 00000002

Can access the Classic's hard drive while the Classic is set to Chooser then connected. Nothing can be written to the disk, but I did get to back up After Dark like I wanted

575:

Classic Sadmacs with code 0000000F 0000000C

575 locks up during the OS Boot

Power Mac 5500:

Classic either boots up normally with the Power Mac, but they do not detect eachother, or idles with a ? over the floppy disk and the Power Mac can access its disk, but write nothing to it.

 

[protocol7]

I wouldn't trust my tapwater so I picked up some de-ionised water. Is it enough to just leave the board soaking in it? And for how long? The comment in that flickr stream said 2 days. But I don't think I'll add any detergent to it.

For now I'm hoping a clean will fix it up (this is what I'm getting right now). I'll tackle the re-capping at a later date when I get the right equipment.

Also I'm guessing there were different revisions of these boards? Mine only has 2 ROMs rather than the 4 shown in these pictures.

 

[Dog Cow]

So far, I've board-washed a Classic, a IIci, a IIe, and an LC III.

Same procedure: take all of the components such as batteries, cable, and SIMMs off. Run water over the board and wipe with a clean rag to get off dust, dirt, and other undesirable matter.

Then I fling water off the board by flapping it in the air, very hard to get the water droplets out of the small spaces, while maintaining a good grip on it. Then I place it over a gas heater to dry out.

I replace it the next day and everything works fine.

 

[protocol7]

That sounds good. I've just left it sitting in some of the de-ionised water. When I was pouring it in I aimed at the areas where I could see some of the goop. So I'll leave it sitting in that till tomorrow and have a look at it. Give it a wipe down if needed. Then I'll put it on the shelf over my hot water tank for a day or so to fully dry out.

 

[Damian Ward]

I thought I would give you an update as the pictures and comment on Flickr are a few years out of date.

I soak the board I a suitable container with a de-ironised water tiny amount of detergent for two to three hours. Then I rinse the board and let it soak in cold de-ironised water overnight with out any detergent. I then dry the board as best as I can, and leave it for a few days in a warm place to totally dry out. As long as you make sure that the board is totally dry, you should not have any problems. I have bought many Macs back to life by just washing the board and I have never had a problem.

BTW, I only use de-ironised water because of the hard water in my area. If you water is better, you should be okay just using that.

I hope this helps.

 

[protocol7]

Hi Damien. Thanks for getting in touch. The water here is pretty hard too, hence my use of de-ionised water as well.

I've just put the board back in and it fired up straight away. I'm going to leave it sitting for a while to see if I hear any wailing from the speaker (yeah it's back whistling again). After leaving the board to dry for a couple of days above the hot tank I noticed a faint cloudy white residue on the board around all the capacitors. So I guess all of them must have leaked but it just wasn't apparent from the first look. I've noted down the capacitors on the board so a full re-cap will be the next operation.

Regarding this residue, maybe I should have used a little detergent after all?