Adcom GFA-555 fuse stuck



Hi there,

I've got an Adcom GFA-555, which I use with a pair of Infinity Kappa 8 speakers.

I was running pretty loud on some low frequencies, and I lost all power from the amp. I figure the Kappas were just drawing too much current, since the woofers can dip down to around 1 ohm with low frequencies.

The power light doesn't turn on, so it shouldn't be thermal shutdown or the transistor fuses. I opened up to check, and they are all fine (I put in 4.5 amp fuses instead of the 6 amp ones spec'd to give me a little safety room). After cooldown it still won't turn on.

I didn't see any scorched components either, but I know from personal experience that that doesn't necessarily mean that there aren't any burned out components. I don't smell anything, at least.

So I'm pretty sure the problem is that the power fuse is blown. The problem is, the screw-in plastic holder is cracked in a couple of places, making normal extraction with a screwdriver impossible.

I thought about trying to super glue it, but I doubt that would hold (and I don't have any on hand any way). I suppose I could epoxy an old screwdriver on to it...

I'm pretty stumped as to what to do - I generally tackle this kind of stuff myself, although at this point I know I need a replacement holder in addition to the fuse anyway.

My only thought is to take it to a general electronics repair shop - there's no real audio repair shops in town AFAIK, and the nearest Adcom authorized repair shop is an hour and a half drive away. As long as it's just the fuze, it shouldn't be that difficult of a job - which is why I'd like to do it myself if possible.
blackbeardben
It's hard to tell what's wrong from your description...a picture certainly would help. I'm sure a call to Adcom would either turn up the fuse holder part...or a suggestion on what to get. Most fuse holders use the same size hole, so if you don't care about it being "authentic" you could probably buy a replacement most anywhere.
Here's a photo of it. You can see that there are four cracks in it as well as it being partially stripped. When I try to turn it, the parts just separate from each other.

http://blackbeardben.smugmug.com/gallery/11634641_vg2iQ#820262200_ZuxBx
I would take a disk of plastic and cut a slot in it that will accept a screw-driver, then glue it flat to the outside face of the fuse holder, making sure that each of the pieces of the old fuse holder are bonded to the plastic disk. Epoxy might be the best bet; you can always heat it to break the bond if you cannot get a new fuseholder, then epoxy the pieces of the old one together (or maybe just keep it glued to the old one and use it that way).
That's a great idea. I didn't think about epoxying something else to it - I've got a spare knob that might work well. That way I'd never have to worry about using a screwdriver for it again.