Sony TC-K707ES Cassette Deck - Door does not consistently open

[BilboBaggins]

I purchased this deck about two years ago. It had an issue with the door not opening consistently so I got it cheap. I took it off the shelf to work on it last year for a few days, and today, I decided to bring it back out to try and figure out what I need to do.

On first look, I realized I changed a belt for a rubber band last year. Had one lying around and no belts. So I know I need to replace the belts. There are at least two of them. I'm now wondering if the door opening issue is related to an incorrect or failing belt that will get replaced. However, I don't want to order a belt kit and then order something else afterwards if I can avoid it. So I'm wondering if there is any Sony ES known issues relating to the door not opening consistently. It closes fine every time.

Finally, can anyone suggest where to get a belt kit for the Sony K707ES cassette deck? I've had some bad luck in the past.

It is a really nice deck. It played fine at first, but I noticed speed distortion, so I'm thinking that rubber band is starting to fail.

 

[Hajidub]

Bob has a belt kit for that, shipping to Canada is steep, like everything else from US to Canada ($12.50). I've used Bob many times and his belts have always been good for me. When you replaced the belt you have to align the mode cam to the mark or the deck thinks it's in "play mode" which won't let the door open. The service manual is available on hifiengine.com and is detailed and super easy to read (follow). Check out section 2.6 which shows the mode cam.

http://www.vintage-electronics.net/sony-tc-k707es-belt-kit.aspx

 

[BilboBaggins]

Bob has a belt kit for that, shipping to Canada is steep, like everything else from US to Canada ($12.50). I've used Bob many times and his belts have always been good for me. When you replaced the belt you have to align the mode cam to the mark or the deck thinks it's in "play mode" which won't let the door open. The service manual is available on hifiengine.com and is detailed and super easy to read (follow). Check out section 2.6 which shows the mode cam.

http://www.vintage-electronics.net/sony-tc-k707es-belt-kit.aspx

Thanks so much Hajidub!

This is exactly what I’m looking for, and may be the answer to my problem. I’ll order a belt kit ASAP. Unfortunately shipping between Canada and the US always comes with extra costs. Probably why I didn’t order a kit a year ago.

 

[BilboBaggins]

Well, I got my belt kit on Wednesday, and went in to change the belts last night. I don't know what it is, but I can't seem to disassemble the unit to the third tiny belt, nor am I able to do the adjustments that @Hajidub mentioned above. I will try again this weekend during the daytime.

 

[Hajidub]

Well, I got my belt kit on Wednesday today, and went in to change the belts last night. I don't know what it is, but I can't seem to disassemble the unit to the third tiny belt, nor am I able to do the adjustments that @Hajidub mentioned above. I will try again this weekend during the daytime.

If I can find the YouTube video I’ll post it.

 

[BilboBaggins]

If I can find the YouTube video I’ll post it.

Thanks! I’ve looked for one, but no luck.

I even had trouble removing the cassette door. In the end, I pushed in the tabs on each side so I could pull the door all the way open. The latch only opened the door about 30 degrees.

I wonder if my version was a later run where they had changed the design a little, or an early version. I’ll check the s/n. The serial number is 700085. Possibly an early one? I studied the service guide for hours with the mechanical assembly out and in front of me.

 

[BilboBaggins]

So I took it apart this afternoon. I had to disassemble a lot more than I wanted to, but I was able to replace the tiny belt, and I thought I had aligned the door opening cam, but I guess I didn’t do it right. There was a thread I was looking at yesterday that had some nice pictures of how it should go, but could I find it again today? No Way! I think it was on TapeHeads, but not sure anymore.

The best part of it, is that I was able to figure out where a couple of long thin screws went that I had left over last night, and fast forward, rewind, and play are working fine. But the door still won’t open. I’ll have to go back in tomorrow. Maybe I’ll find that thread now that I’m not searching for it.

Here are some pictures.

 

[BilboBaggins]

I just found the thread I was referring to on Tapeheads.

http://www.tapeheads.net/showthread.php?t=57451

Based on the last two pictures in that thread, and the pictures I took before reassembly in post #7, I did it correctly. Darn! That means it is something else. Tomorrow I will go in again. There may be something binding in the door open assembly that is binding and causing too much resistance. I did find the Boss Gear in position B in the Tapeheads thread and corrected that, and the mode assembly was also off.

 

[Hajidub]

I just found the thread I was referring to on Tapeheads.

http://www.tapeheads.net/showthread.php?t=57451

Based on the last two pictures in that thread, and the pictures I took before reassembly in post #7, I did it correctly. Darn! That means it is something else. Tomorrow I will go in again. There may be something binding in the door open assembly that is binding and causing too much resistance. I did find the Boss Gear in position B in the Tapeheads thread and corrected that, and the mode assembly was also off.

Sorry Bilbo, I looked all day yesterday for the video I saw but it must have been removed, sorry man. Post your question on TH's, those guys are crazy tape geniuses and will know the door issue. Glad it works though, it's a lifetime keeper.

 

[BilboBaggins]

Sorry Bilbo, I looked all day yesterday for the video I saw but it must have been removed, sorry man. Post your question on TH's, those guys are crazy tape geniuses and will know the door issue. Glad it works though, it's a lifetime keeper.

Thanks for looking Hajidub! Who says that things posted on the internet are forever? There are many articles and threads that disappear over time. It is only the stuff you don’t want to find that seems to stay forever.

I am optimistic now though, since I figured out how to get deep inside. Now that I know how, it isn’t too bad, but I spent a lot of time turning it over and over trying to figure out how to get inside to that small belt.

If I strike out tomorrow, I will post at TH. There is definitely a lot of knowledge and skill on that site.

 

[BilboBaggins]

@Hajidub Success!

It turns out when I was reassembling the transport yesterday, a small gear came off its position in the area around the small belt. It was causing the same symptoms as before because it drives the door. On reassembly, I was putting back the pivot gear on the cassette side of the assembly, and that little nylon lock washer disappears as I am putting it in place! I looked for it, and couldn't see it anywhere. I checked my clothes, all over the transport, and it was gone! My best guess was that it fell inside where the small belt goes, so back to de-assembly. There it was! I put everything back together, and the door opened on power up! Tested it a few times and that was good! Tried fast forward and rewind, all good. Then I tried play. That didn't work immediately, but after fast forwarding and rewinding my test tape a few times, playback started! Success!

Thank you so much for your help! You pointed out that mode wheel that I had missed when reading the SM. Another great deck back in use!

All in all, I agree with something I read about these transports. Very easy to work on once you figure out the sequence to disassembly. I think I do a de and re in about 45 minutes max now. It is very intimidating at first, but if you are organized in how you take things apart, take your time, and take lots of pictures, it is not too bad to work on. Now to enjoy the music!

 

[Dr Him]

@BilboBaggins I just found this thread last night after replacing the 3 belts in my K707ES and finding similar symptoms (eject not working, I can manually open but not open the door all the way).

I never got the mechanisms fully disassembled - I managed to get apart enough where I could feed the smallest belt on.

I'm hoping with your pictures now I can figure it out... the service manual didn't go into details on this, that I could see.

So you think the issue was "a small gear came off its position in the area around the small belt"? I hope I can get to it to see if mine is the same.

 

[BilboBaggins]

Hi Dr Him! Actually, I think that mode wheel is one issue that affects the door opening, and that gear that came off is the other. Take your time, take lots of pictures from different angles, do not leave it apart before you stop working. In my experiences, once you have stepped away from the unit for a day or more, your memory on where everything goes starts to fade. Once you've taken it apart and put it back together a few times, it gets easier.

I have a nice Akai 3 header I did that with. Now it has been apart for over 2 years and I doubt very much I will ever get it working. Thankfully, I bought it when these nice three head decks were going for $5 - $10 at thrifts, so it isn't a huge loss. It is the potential value that I hate losing.

 

[Dr Him]

Aye; agreed on the "don't leave it apart" advice.

I'm still totally mystified how to disassemble it enough to get to that tiniest gear, but you've given me hope!

I actually bought this tape deck brand new in 1995. Would be cool to get it running again.

 

[BilboBaggins]

I hooked mine back into the critical listening room system last night. Listened to it all day today and quite enjoyed it. I had a JVC TD-R411 in that system, and I've been trying to sell it. I think I need better pictures and that won't happen there. So yes, well worth the effort.

I can't remember how I got it fully apart anymore. If I do take it apart again, I'll post how on this thread. I have quite a few decks that need looking at, as I discovered yesterday.