Audiokarma.org
Audiokarma Featured Sponsor

Go Back   AudioKarma.org Home Audio Stereo Discussion Forums > Tape


We appreciate your help

in keeping this site going.
Reply
 
Thread Tools Display Modes
  #1  
Old 05-08-2009, 12:27 AM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
Akai GX-77 belt replacement & tune-up?

I received a GX-77 recently as part of a purchase of some Bose 901 speakers. It was a "buy it all or nothing" kind of deal.

The GX-77 is in non-working condition. So I opened it up and I see there is a tiny thin little belt that is broken. I'd like to replace this and also do a basic tune-up with alcohol while I've got it apart.

Is there just the one belt that needs to be replaced, or are there other belts that I just didn't notice? I could only find one belt on the Internet to purchase for it. But there were occasional references to more than one belt in the machine?

Other than cleaning everything with alcohol & replacing the belt(s), what else should I do?

What will I do with a reel to reel? I remember growing up in the 70's and my Dad had a reel to reel that he loved and would frequently clean. But I don't have a tape colllection. Just the tape that came with this unit that is labeled "a bit of this and a bit of that".
Reply With Quote
  #2  
Old 05-08-2009, 01:17 AM
inductor inductor is offline
AK Member
 
Join Date: May 2005
Location: uk
Posts: 1,016
the reels are driven thru belts if i remember correct
Reply With Quote
  #3  
Old 05-08-2009, 01:58 AM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
I'll have to take the unit further apart then, I suppose. Thanks!
Reply With Quote
  #4  
Old 05-08-2009, 09:44 AM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
Yep, I found there is at least one more belt, a diamond shaped one in the front compartment.

Does anyone know which is which when it comes to part numbers? I only need to replace the one in the back compartment.
Reply With Quote
  #5  
Old 05-08-2009, 10:21 AM
MoreCowbell's Avatar
MoreCowbell MoreCowbell is offline
AK Member
 
Join Date: Mar 2008
Location: Dallas, TX
Posts: 223
There are three belts in the GX-77. One long thin belt runs both capstan flywheels. Two shorter belts, with a square cross section, run each of the reel tables.

I did a complete overhaul of a GX-77 which wasn't particularly difficult but having the service manual was virtually a necessity. Having a method to keep track of where all of the parts go after you remove them is also a must.

In order to remove the long thin belt, you have to unscrew one of the short support rods. This is done after unbolting the back frame, that contains the transformer, and laying it down. It's a bit of a puzzle but not that bad.

Another thing to check is the small spring that is attached to the tape loading pulley in the front of the unit. They apparently have a tendency to break at the point where the spring attaches to the plastic part that holds it. Sometimes this prevents the player from working.

I purchased the belt kit for my GX-77 from Vintage Electronics.

Hope this helps.


Paul
Reply With Quote
Audiokarma
  #6  
Old 05-08-2009, 04:22 PM
quadraTOMic quadraTOMic is offline
AK Member
 
Join Date: Feb 2007
Posts: 116
I second Vintage Electronics. If you do happen to break one of the springs Cowbell is talking about, and I did, use a ball point pen spring as a replacement. Worked perfect!
Reply With Quote
  #7  
Old 05-08-2009, 11:14 PM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
Thanks, guys! I looked at several places and nobody had a "kit". So I bought the one you linked to above!
I'll try to take pics of the install if you want.
Reply With Quote
  #8  
Old 05-09-2009, 02:26 AM
MoreCowbell's Avatar
MoreCowbell MoreCowbell is offline
AK Member
 
Join Date: Mar 2008
Location: Dallas, TX
Posts: 223
In my case, it wasn't the spring that broke, but the attachment on the plastic part that held the spring. I made a new attachment and also made a new spring with less tension as I thought the original was way too strong. The new spring was purchased at a hardware store and was simply cut to the correct length. Here's a link to the thread that I started regarding the loader spring. It also has a few pictures.

I acquired another GX-77 and it has the same problem. This appears to be a recurring problem with this model.


Paul
Reply With Quote
  #9  
Old 05-16-2009, 09:42 PM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
Quote:
Originally Posted by MoreCowbell View Post
I purchased the belt kit for my GX-77 from Vintage Electronics.
Wow, I got the belts like the very next day after I paid for them. I saved that website to my favs. Thanks.

Quote:
Originally Posted by MoreCowbell View Post
I did a complete overhaul of a GX-77 which wasn't particularly difficult but having the service manual was virtually a necessity.

You're not kidding about needing the service manual. You wouldn't by any chance have a picture album you could share with me of the teardown, would you?

I started the teardown but I'm having trouble getting the front faceplate off and the power transformer out of the way.

Also, I'm not sure of the skinny belt orientation?

Last edited by Strawman; 05-21-2009 at 12:12 PM. Reason: Removed purchase offer.
Reply With Quote
  #10  
Old 05-17-2009, 12:46 AM
MoreCowbell's Avatar
MoreCowbell MoreCowbell is offline
AK Member
 
Join Date: Mar 2008
Location: Dallas, TX
Posts: 223
Quote:
Originally Posted by testwork View Post
Wow, I got the belts like the very next day after I paid for them. I saved that website to my favs. Thanks.




You're not kidding about needing the service manual. You wouldn't by any chance have a picture album you could share with me of the teardown, would you? Or perhaps be willing to sell me your copy of the service manual?

I started the teardown but I'm having trouble getting the front faceplate off and the power transformer out of the way.

Also, I'm not sure of the skinny belt orientation?
I'm currently away on a business trip so I'm not able to take more photos. When I get back I'll take a few pics to help. You really do need the service manual. I got mine free off one of those sites that let people upload manuals. I'll see if I can find it and give you the link.

In order to get the transformer out of the way, you have to cut the zip ties that hold the wire bundles together on the back of the unit. This gives you the slack needed to lay the back frame (with the transformer attached) down.

I was half serious about it being like a Rubic's cube.


Paul
Reply With Quote
Audiokarma
  #11  
Old 05-17-2009, 01:13 PM
testwork testwork is offline
AK Member
 
Join Date: Apr 2009
Location: Central Texas, USA
Posts: 266
I assumed you might have already had a bunch of pics taken. No sense in tearing it apart just to take more pictures.
Thanks though!

The manual link would be appreciated. I'll search for it myself though and post back if I find it!
Reply With Quote
  #12  
Old 05-21-2009, 12:07 PM
MoreCowbell's Avatar
MoreCowbell MoreCowbell is offline
AK Member
 
Join Date: Mar 2008
Location: Dallas, TX
Posts: 223
Here's three pics illustrating how to gain access to the capstan flywheels. I'm not sure if I remembered everything correctly regarding the rear center support bracket, but it will be fairly obvious once you get started.

In the pic showing the flywheels, the bar that holds them in place can be seen. It must be removed in order to replace the belt. The main motor is the small can shaped widget in the lower left of the pic. One of it's support rods must also be removed to allow replacement of the belt.

I sent you a PM. Did you get it?

Good luck.


Paul
Attached Images
File Type: jpg Flywheels.jpg (79.3 KB, 171 views)
File Type: jpg Slide2.jpg (140.9 KB, 165 views)
File Type: jpg Slide1.jpg (153.8 KB, 159 views)
Reply With Quote
  #13  
Old 03-06-2014, 07:43 AM
rockaday rockaday is offline
AK Member
 
Join Date: Mar 2014
Posts: 2
Dear More Cowbell, I've been reading these threads. I just bought a GX 77 as well. I changed the three belts. Your threads and especially the photos were very helpful and thanks. I will refer to direction of the tape rather than fast forward and rewind because it does both in both directions as it plays both ways. Everthing is fine with the new belts except that it struggles to fast wind with tape going from the right reel to the left. I think this may have something to do with a small mechanism I had to remove to replace the two small belts. There was a spring on the part and a belt of some kind going around the spindle that looked like some sort of braking mechanism. I hope I am describing this ok. With this problem I have do you imagine the problem is with the send reel or the take up reel. I have a feeling it is the send reel that is perhaps 'too tight'. thanks for any input you can give .
Reply With Quote
  #14  
Old 03-06-2014, 09:34 AM
KentTeffeteller's Avatar
KentTeffeteller KentTeffeteller is offline
Gimpus Stereophilus!
 
Join Date: Feb 2006
Location: Athens, TN
Posts: 18,279
This deck had very weak motors when new. On a cassette deck, they would have been among the best available. Any tension or other issues only makes that problem worse. This machine was designed for compactness and styling as a priority. The design didn't age well and as the pictures indicate, an intricate thing to service. It's worth love, this model fetches good money to Akai collectors. It is interesting.
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:17 PM.



Friends of Audiokarma
We appreciate your help in keeping this site going.
Stereo Repair World
Herbies Audio Lab
Vintage Home Audio
Amps and Sound
Pro DJ Headphones - click here
Organ Donor Parts
Wargos Electronics
Parts Connexion
Sonneteer
Take Five Audio
Sound Stage Direct
Audio Salon
AudioClassics
Audience AV
AV Solutions
Simply Speakers
Tone Arm Audio
BD Enterprise
Musical Paradise
Howard Products
Classic Sound Repair
FM DX Antenna
McIntosh Cabinets
Siliconray
BOI Audio Works
Vinyl Magic Record Cleaner
Amplifiedparts
Grant Fidelity
RSL Speakers
Yesterday's Audio
Urban Antigue Radio
DeWick Repairs
Many Moons Audio
Vintage Electronics Repair
The Tube Store
Politicalchat.org
Audio Doctor
Antique Radio Classifieds
MCM Electronics
Videokarma.org
   
   
Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
ęCopyright 2002-2014 AudioKarma.org, All rights reserved.