lancianut666 Posted April 30, 2019 Report Share Posted April 30, 2019 Hi all After listening to a mdlp recording of 4 Heart albums for the last 2 years as I couldn't get the disc to eject from my Sony MDS JB 940 QS I thought I would just get on with it and get that belt changed...so after about 40 minutes I tested it and to my dismay C13 flashed up but with a twist the disc now ejected no problem. Off came the lid the 4 screws in the rubber mounts were removed and propped up on 3 Observers books the loader sled unit was at the right height to see what was going on. Basically when you put a disc in it made a half hearted attempt to draw it in failed and then ejected the disc. It seems that with a bit of persuasion the disc will drop down into the correct position do a TOC read and the disc will play OK and when required eject smoothly. The big question is if the sled load motor can eject the disc easily why won't it load properly? The next question is can another MDM-7A be sourced from a similar deck and cure this or is it terminal? Jim Quote Link to comment Share on other sites More sharing options...
sfbp Posted April 30, 2019 Report Share Posted April 30, 2019 The big answer is: because the belt slipped. I think there's a spring that counterbalances (like most of their mechanisms) so that movement in one direction or the other may be slightly favoured. There's no big deal about the belt - it's a fancy rubber band, some used Orthodontic ones but you can buy selections of O-rings here https://www.ebay.com/itm/225Pcs-Rubber-O-Ring-Washer-Assortment-Set-Hydraulic-Plumbing-Gasket-Seal-Kit/172535750679 Good luck! Stephen Quote Link to comment Share on other sites More sharing options...
lancianut666 Posted May 1, 2019 Author Report Share Posted May 1, 2019 Hi Stephen I changed the belt and noticed a spring that had come off I put this back as I thought it should be ...perhaps I need to revisit this again. I tracked down a youtube video where a very knowledgeable Russian guy dismantles the whole sled/laser unit but my Russian is non existent . Jim Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 1, 2019 Report Share Posted May 1, 2019 Make sure the rack moves properly. Did you use the specified belt or guess? It may be that it needs to be tighter (compare 7:55 and onward). My recollection is that when it's right, it was always hard to get on. If you slipped it on easily, it's not the right belt. Quote Link to comment Share on other sites More sharing options...
kgallen Posted May 3, 2019 Report Share Posted May 3, 2019 On 5/1/2019 at 8:39 AM, lancianut666 said: Hi Stephen I changed the belt and noticed a spring that had come off I put this back as I thought it should be ...perhaps I need to revisit this again. I tracked down a youtube video where a very knowledgeable Russian guy dismantles the whole sled/laser unit but my Russian is non existent . Jim Jim - thanks for sharing that video! I just replaced the load belt on my "new" eBay rescued MDS-E10 in about 5 minutes! (5/16" ortho band, seems tight enough). However I'm still having load problems. The deck still won't pull the disk in. Can't see any obvious problems in the disk mechanism - nothing apparently broken, missing or springs unattached, everything smooth. Seems the disc mechanism won't initialise properly either - it tries for a bit then ends up with "IIC Stop" message when it gives up. It's an eBay rescue deck, but it's in immaculate condition, seems hardly used - probably because of this issue! Sorry, not intending to hijack the thread, just sharing the "pain"! Kevin Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 3, 2019 Report Share Posted May 3, 2019 IIC stop is referring to the control bus. If that's broken, all bets are off. You need to check ALL ribbon cables very carefully, with a multimeter. Good luck! Quote Link to comment Share on other sites More sharing options...
kgallen Posted May 4, 2019 Report Share Posted May 4, 2019 Spawned out my own fun and games to a new topic to avoid hijacking Jim's thread. Quote Link to comment Share on other sites More sharing options...
lancianut666 Posted May 4, 2019 Author Report Share Posted May 4, 2019 Hi Stephen I changed the belt and noticed a spring that had come off I put this back as I thought it should be ...perhaps I need to revisit this again. I tracked down a youtube video where a very knowledgeable Russian guy dismantles the whole sled/laser unit but my Russian is non existent . Jim No problem more the merrier Quote Link to comment Share on other sites More sharing options...
lancianut666 Posted May 4, 2019 Author Report Share Posted May 4, 2019 The belt was from an ebay source for the 940 deck thing is it will play OK if you help it to draw the disc in and it ejects no problem so I think I will have to dismantle it again Quote Link to comment Share on other sites More sharing options...
sfbp Posted May 4, 2019 Report Share Posted May 4, 2019 Often the problem is the other way around. I would be inclined to look carefully at the manual and see what the resting position for that rack is. Maybe it has to be moved one tooth either way. Quote Link to comment Share on other sites More sharing options...
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