I have a problem with the 3-cd changer component of an Aiwa all-in-one system. The problem is that the player keeps leaving a mysterious residue on CDs, always at the same distance from the center and no matter which position (1/2/3) the disc is in the tray.. The residue comes off OK but seems to be slightly abrasive as sometimes removing it leaves small scratches on the CDs. I have tried cleaning the lens and the tray; if this has any effect it is only temporary as this problem has been going on for some time now. Any insights would be appreciated!
Having repaired literally hundreds of the 3-player mechs in these over the years, I really can't think of anywhere that this can be coming from. For it to keep doing it, there would have to be a significant quantity of whatever it is. I would have expected that, this being the case, you would have been able to easily spot it. I'm assuming that whatever it is that gets on there, is smeared around in a 'ring' on the disc ? Whilst the disc is on the turntable, the only thing that comes close enough to the disc to thus 'spread' something that had been picked up as a spot whilst the disc was being rotated on the carousel, is the lens. This being the case, you would expect to then see something on the top of the lens after the event has occured. Further, I would have expected the ring to be spread elsewhere on the disc surface, by the passage of the lens across the disc - at least until it had thinned it enough for the lens to no longer be able to touch it.
There is actually very little grease used on this deck. The majority of the open / close and sub-deck lifter gearing ( the blue gear, the black and white gears, and the yellow rack slide ) are made from an oily plastic like polythene, and run dry on their contact surfaces, although I seem to remember that they might have silicone lubricant on their shafts. The only other place that there is a significant quantity of grease, is on the carousel worm drive, but this is located right underneath the tray, so I can't see how any grease could get from there, onto the upper surface, where it could get picked up by the disc.
It's a mystery, but one I would have thought that you could have got to the bottom of by careful examination of the mech. If the contamination always appears in the same place, then it should be an easy enough job to project the band where it could be getting on the disc, onto the carousel, because I'm sure that's where it *must* be getting on there, rather than from the deck area, and then rotating the tray manually by working the worm gear with a finger ( you can just get to it with the tray open ), and watching all the way round, through one of the disc slots in the carousel. As I am very familiar with this mech, I am most intrigued to know what it turns out to be, so please share when you do find out.