Akai GX-747 issues

[plex]

I have an Akai 747 RTR i am trying to clean pot and switches but I don't know how to access them.  I've taken off the front panels but can figure how to remove the face plate were the LED meters and other switches are.  I've removed the knobs for the mic & tape input level but there is some type of plastic fingers holding on the back plate under these knobs that is keeping me from removing that faceplate to I think access those pots and switches.

The problem I'm having is when I play back a tape one channel is almost dead or very little output.  Now at times the tapes players find and you hear a full range audio, but if I stop the tape and hit play again that same channel is gone and the sound is very flat.  Could it be a relay that loosing contact, if you stop and start the tape and not a switch or dirty pot.  At times you can almost hear it trying to come through but it just not.

I would like to fix this on my own, I already have my 9000DB and 4 JBL drivers in for repair, I don't want to put my RTR in for repair.

[MacGeek]

At the risk of stating the obvious, have you given the heads and tape guides a good cleaning?  How old is the tape; some will deteriorate and leave a mess.

[plex]

Never hurts to ask, and yes all clean

[schwarcw]

I think that you have to remove the front panel from the back.  A number of big R2Rs have this nasty inconvenience.  Have you tried to download a service manual online?  Many are free, some are worth the $20 if it save you a lot of work or avert possible damage.

Good luck!

[Reverend]

There's a service manual at Hifi Engine.

http://www.hifiengine.com/library/akai/gx-747.shtml

[plex]

Everything is now cleaned and the feel of the pots and switches is better, sharp click and not thuds, but no change in output.  I have noticed that if I turn off the player for several hours and start playing again it works fine until I change playing or change directions and/or stop and start playing.

If it is a relay issue can I clean the contacts on a relay or at least test them to find out if this is the problem.  I would like to not dismantle the RTR to do this, otherwise it will be easier to have it added to the items that need repaired.

[MacGeek]

Depending on the relay, cleaning them is not hard.  Getting to them often is.

[plex]

Do I have to unsolder them or can I remove the cover and clean them

[MacGeek]

If you can get to the board on which the relay is mounted, there is usually a protective cover or cap over the top of the relay.  Pop the cover to expose the contacts and use a small newspaper strip or something similar soaked in DeOxit for cleaning.  Put the paper strip between the contacts, switch the relay closed and gently push/pull the paper back and forth across the contacts.  The newspaper functions as a mild abrasive and in combination with the Deoxit, does a very good cleaning job.  Use a new/c;ean paper strip for each contact.

If the problem goes away--success.  If not, either it's not the relay, or the contacts are worn or burnt and the relay needs to be replaced. If that is the case, there is no harm in trying something more abrasive as a cleaner, but good luck with that.