Thursday, January 12, 2017

Apple Mac Classic II Repair - Part 2

So after a lot of cleaning, the Mac still refuses to boot and gives us the stripes of death. What to do. I have capacitors on order (for the grand sum of about £3.50) but I was worried that, even after replacing the caps, I might still have the same issue. The stripes are not caused by a failure of the capacitors, rather, the electrolyte leaking out of the capacitors and short circuiting various parts of the motherboard.

Stripey..

A lot of Googling has shown that in many cases, the extreme measure of putting the main board in the dishwasher has cured many problems such as the one I have with this Mac. I would normally dismiss this type of idea as being completely insane but so many different sites suggested it as an extreme, but practical solution I thought I might give it a try.

Brace yourself...
Yes, I put my vintage Apple Mac motherboard in the DISHWASHER.

I set it going early this morning on a cool wash (normally reserved for delicate cups and glasses) and then, after 20 minutes, put it in a warm cupboard - where my boiler sits - and left it to dry out for the rest of the day.

Fast forward to 8pm tonight (Thursday 12th January) and it's time to put it back in the case and see if I've destroyed it...

It's Alive!

Nope. It boots. I am STUNNED. Sticking it in the dishwasher and then letting it dry out for 12 hours actually worked!

For anyone who might want to try this, bear in mind that I removed the battery (it's dead anyway), the ROMs (two chips - some Classic II's have four apparently) and the additional RAM before it went for a bath.

But we do have a problem. Notice that there is a floppy disk icon with a question mark in it? That means it can't see the hard disk or, at the very least, there's no operating system to boot from on it. Now I need to get some system disks. This was relatively easy but as the copyright around this is a bit vague I will say no more.

Incidentally, there was a floppy disk stuck in the drive. I hadn't spotted that there was a hole next to the slot for the disks which, on the Mac, acts exactly like the little hole in the CD tray for when you can't get your CD out of CD draw. One unfolded paper clip and a hefty shove later and the disk was released. Whether it was left in there because the machine went faulty or whether it was left in there by accident and then it was sold or abandoned I don't know. Either way, I got it out.

Talking of floppies, my excellent Dad gave me a USB floppy drive over Christmas, and it has been THE most useful thing ever for this project. I managed to write a 'Disk Tools' disk from System 7 and booted from that. I also managed to write all the other System 7 disks too which will be very useful.

Welcome indeed!
Once up and running I ran the disk setup utility and asked it to scan the SCSI bus for a hard disk. This was the result:

Bugger.
Oh dear. It looks like the hard disk has gone kaput. Hardly surprising, given its age. The only snag is that I think the only SCSI drives I have are about 36Gb and I'm not sure that this Mac would cope with that... More Googling required to see if I can use them - assuming I can find them in the box of bits upstairs!

I should point out that I managed to do all this without the keyboard attached. The cable I've ordered (for £2 - big spender) hasn't arrived yet but the mouse can plug straight into the back without needing the keyboard.

One final thing in this post. Although he's up and about, it doesn't mean that this is the end of the repair, and he's not out of the woods yet. The capacitors on that board are toast. The amount of electrolyte that was on the board can only mean that the problem WILL re-appear. So I am going to replace the capacitors anyway to ensure that this machine keeps going for another 20 years.

1 comment:

Tim Robson said...

Did you put a detergent tablet in the dishwasher too?