Akai 4000DS tape speed problem
 

Hello.

I’ve managed to get myself 2 pieces of beatiful japanese technology (Akai 4000D and Akai 4000DS) both in very nice shape. My main tape deck was that DS until now because I don’t really want to abuse those cams of 4000D much.

Now straight to my problem. When I got it home it played normal. Then after some days it had to run for a while before it sped up up to speed. So I changed main belt and degreased felt clutch of the right spindle. And now? Now it plays up to speed only when I leave the tape spilling on the floor without it winding on right reel. When the tape is put though tape path correctly it just plays slower. Comical is that fact, that my tapes were recorded on this DS and it plays it back slower - my 4000D plays it at the right speed...
Does anyone have any advice?

Thank you.

(I also hope it is understandable...)

Re: Akai 4000DS tape speed problem
 

Sounds like it is the supply (left) reel clutch, felt pad or excessive tension (adjustable) it has come up before in this thread;
https://www.vintage-radio.net/forum/...=147405&page=2

Re: Akai 4000DS tape speed problem
 

These clutches are very finicky it sounds like you have too much tension on the right hand clutch, and/or the pulley that drives the RH spool is in FF mode because of dried up grease.

Re: Akai 4000DS tape speed problem
 

So I've managed to loosen up those felt clutches to lower the tension a little bit - it did speed up a little bit. But now it has problem with rewind and fast forward - degreased surface of every wheel many times. I also found out that if I push with a screwdriver on axis (little bit) of that rubbered wheel between motor and right spindle it speeds up yet closer to original speed...

Re: Akai 4000DS tape speed problem
 

Almost certainly the idlers have gone hard and no longer grip. Send them to terrys rubber rollers for rebuilding.