Teac cx-350 stops playing

[Lorenzenjohn]

I have a teac cx-350. I replaced all belts and pinch roller, cleaned switches. It continues to stop during playback. There is a spring attached to the, what I think is the “ tape load” switch that I may have in the wrong orientation. Please help

 

[Tony75]

Hi,
It's been a long while since I have done on of those decks, but I have worked on many of that mechanism. I'm not too sure on the spring you mention, a picture will help here.
What I am thinking though is that it is not actually this spring but indeed a clutch in the auto-stop mechanism. This (from memory) is driven off the rotating take-up spindle. The clutch makes a rocking arm push against a cam that moves back and forth. When this rocking arm does not have drive, it sits in the middle and hits an auto-stop trip pin, making the deck stop. To find this you will have to look and study how the deck works, but it is fairly straight-forward.
When this clutch pad wears, it no longer provides enough torque to push this cam onto one side, causing the autostop to trip.
Back in the day you could easily buy kits of clutch pad material, pre-cut in round shapes with holes. These days you will probably have to make your own. Don't be tempted to make it much thicker than what is already there, it just has to be less shiny. You may have some success with roughing up the felt pad.
Not sure what material I would recommend these days for replacement, the self-adhesive stuff for the bottom of furniture is way too thick, but something along that track will be what you need.
I can access my decks, but photographing them to show you what I mean could be quite difficult.
Cheers
Tony

 

[Lorenzenjohn]

Ok Tony, bear with me. I discovered the small straight spring resting on that tab was not in place at reassembly. I put it in place and now It plays without interruption . The coiled spring is the one I was referring to in my original message. Now that I have it running it does not auto stop! So now its a different problem. Thanks so much for your expertise. Looking forward to your response. I’ve learned a lot already

 

[CaptainWins]

Hi Tony75,

I think I’m experiencing exactly what you describe but with a CX-400. About half or 3/4 of the way thru a tape (depending on duration) the auto stop kicks in. This happens with any and all kinds of tapes...
I’m having trouble locating the felt clutch. How does one get to this clutch? From the front/back? Does the whole mechanism need to be removed? I can’t find a manual for the CX-400 and can’t locate the clutch’s position in schematics of closely related decks.
Any instructions or advice you can offer would be much appreciated!
Thanks in adavance!

Video of auto stop kicking in...

Hi,
It's been a long while since I have done on of those decks, but I have worked on many of that mechanism. I'm not too sure on the spring you mention, a picture will help here.
What I am thinking though is that it is not actually this spring but indeed a clutch in the auto-stop mechanism. This (from memory) is driven off the rotating take-up spindle. The clutch makes a rocking arm push against a cam that moves back and forth. When this rocking arm does not have drive, it sits in the middle and hits an auto-stop trip pin, making the deck stop. To find this you will have to look and study how the deck works, but it is fairly straight-forward.
When this clutch pad wears, it no longer provides enough torque to push this cam onto one side, causing the autostop to trip.
Back in the day you could easily buy kits of clutch pad material, pre-cut in round shapes with holes. These days you will probably have to make your own. Don't be tempted to make it much thicker than what is already there, it just has to be less shiny. You may have some success with roughing up the felt pad.
Not sure what material I would recommend these days for replacement, the self-adhesive stuff for the bottom of furniture is way too thick, but something along that track will be what you need.
I can access my decks, but photographing them to show you what I mean could be quite difficult.
Cheers
Tony

Hi,
It's been a long while since I have done on of those decks, but I have worked on many of that mechanism. I'm not too sure on the spring you mention, a picture will help here.
What I am thinking though is that it is not actually this spring but indeed a clutch in the auto-stop mechanism. This (from memory) is driven off the rotating take-up spindle. The clutch makes a rocking arm push against a cam that moves back and forth. When this rocking arm does not have drive, it sits in the middle and hits an auto-stop trip pin, making the deck stop. To find this you will have to look and study how the deck works, but it is fairly straight-forward.
When this clutch pad wears, it no longer provides enough torque to push this cam onto one side, causing the autostop to trip.
Back in the day you could easily buy kits of clutch pad material, pre-cut in round shapes with holes. These days you will probably have to make your own. Don't be tempted to make it much thicker than what is already there, it just has to be less shiny. You may have some success with roughing up the felt pad.
Not sure what material I would recommend these days for replacement, the self-adhesive stuff for the bottom of furniture is way too thick, but something along that track will be what you need.
I can access my decks, but photographing them to show you what I mean could be quite difficult.
Cheers
Tony

Hi,
It's been a long while since I have done on of those decks, but I have worked on many of that mechanism. I'm not too sure on the spring you mention, a picture will help here.
What I am thinking though is that it is not actually this spring but indeed a clutch in the auto-stop mechanism. This (from memory) is driven off the rotating take-up spindle. The clutch makes a rocking arm push against a cam that moves back and forth. When this rocking arm does not have drive, it sits in the middle and hits an auto-stop trip pin, making the deck stop. To find this you will have to look and study how the deck works, but it is fairly straight-forward.
When this clutch pad wears, it no longer provides enough torque to push this cam onto one side, causing the autostop to trip.
Back in the day you could easily buy kits of clutch pad material, pre-cut in round shapes with holes. These days you will probably have to make your own. Don't be tempted to make it much thicker than what is already there, it just has to be less shiny. You may have some success with roughing up the felt pad.
Not sure what material I would recommend these days for replacement, the self-adhesive stuff for the bottom of furniture is way too thick, but something along that track will be what you need.
I can access my decks, but photographing them to show you what I mean could be quite difficult.
Cheers
Tony

 

[skywavebe]

The clutch is on the reel table. You can look at many CX model decks as the mechanism was almost the same. The auto shut off is related to the part that Tony was talking about and concerns the reel table pin in the back pushing a reset arm to the side. When the reset arm is not pushed by a rotating reel table on the right the reset arm being in the middle is pressed on and actuates the stop function. Felt can get dry and some reel tables I have taken apart have like a white powder in them. I don't know if this is from the plastic or the felt glue but just like brake pads the felt does not last forever and needs to be changed. Any kind of felt size can be had from McMaster Carr and even some too thick for a job I have compressed in a vise. You do not have to get the self stick stuff as buying a 12" square piece for a 3/4" round cut out will be a waste unless you work on stuff all the time like me. The reel table assembly is part of the one center assembly so they do not tell you about individual parts on this assembly like reel tables. You need to take parts off of it and examine what part is not working and I would start at the takeup reel table. I have a few CX decks here I can look at. The straight spring I think is part of the pause shut off defeat.

 

[CaptainWins]

skywavebe -

Thanks so much for your very helpful reply. Do you agree that a worn out faulty felt clutch explains this behavior (play perfectly for first ~25min, then intermittent rest of way)? Hopefully I have attached a still from a CX-400 rebuild video on Youtube. Is the felt clutch in question just barely visible in the still? If yes, is it just a matter of removing the face plate and pulling out this RH take up reel to gain access? I think I could that. Or is it more involved than that....?
Again, thanks so much for all of the helpful info.

The clutch is on the reel table. You can look at many CX model decks as the mechanism was almost the same. The auto shut off is related to the part that Tony was talking about and concerns the reel table pin in the back pushing a reset arm to the side. When the reset arm is not pushed by a rotating reel table on the right the reset arm being in the middle is pressed on and actuates the stop function. Felt can get dry and some reel tables I have taken apart have like a white powder in them. I don't know if this is from the plastic or the felt glue but just like brake pads the felt does not last forever and needs to be changed. Any kind of felt size can be had from McMaster Carr and even some too thick for a job I have compressed in a vise. You do not have to get the self stick stuff as buying a 12" square piece for a 3/4" round cut out will be a waste unless you work on stuff all the time like me. The reel table assembly is part of the one center assembly so they do not tell you about individual parts on this assembly like reel tables. You need to take parts off of it and examine what part is not working and I would start at the takeup reel table. I have a few CX decks here I can look at. The straight spring I think is part of the pause shut off defeat.

 

[CaptainWins]

Looking for the felt clutch...I think I’m warm but all I see is an extremely thin metal(?) washer.
Do I need to extract this two part white spring loaded part to get to the felt clutch? And if so how? Feels like I’m going to break something. If it’s not obvious already, I really don’t know what I’m doing, so if you could dumb it down as much as possible it would be most appreciated.
Thanks to anyone who can point me in the right direction.

The clutch is on the reel table. You can look at many CX model decks as the mechanism was almost the same. The auto shut off is related to the part that Tony was talking about and concerns the reel table pin in the back pushing a reset arm to the side. When the reset arm is not pushed by a rotating reel table on the right the reset arm being in the middle is pressed on and actuates the stop function. Felt can get dry and some reel tables I have taken apart have like a white powder in them. I don't know if this is from the plastic or the felt glue but just like brake pads the felt does not last forever and needs to be changed. Any kind of felt size can be had from McMaster Carr and even some too thick for a job I have compressed in a vise. You do not have to get the self stick stuff as buying a 12" square piece for a 3/4" round cut out will be a waste unless you work on stuff all the time like me. The reel table assembly is part of the one center assembly so they do not tell you about individual parts on this assembly like reel tables. You need to take parts off of it and examine what part is not working and I would start at the takeup reel table. I have a few CX decks here I can look at. The straight spring I think is part of the pause shut off defeat.

 

[skywavebe]

I would have to take one apart to see what is the detail of the part. Many parts are press fit together or may have little catches. There are no detailed diagrams of this as the whole thing is an assembly they wanted to sell you. Now days when you have to fix these with no part it becomes necessary to take things apart the right way and make corrections that are needed that normally were not done in the olden days. If the auto shut off is stopping the machine it needs to be determined if the lack of reel drive is the cause or the lack of the arm pushing the stop part out of the way. Typically felt become too frictional not less and that is why I am always changing brake pads on open reel decks. It also happen in reel tables on some units as the take up toque can go as high as 100g/cm when it is suppose to be 35-45g/cm all due to dried out felt. I tell my trainees to not jump to conclusions without knowing what you are really dealing with which is all right there in front of you if you observe correctly. If a reel table tire is cracked or has lack of drive the reel table will not spin with increase drag from a full reel of tape and so this will cause the auto shut off to trigger as the reel actually stop turning- that is a different problem than an auto shut off problem itself. There is also the possibility that there is a dead spot on the reel motor to consider- when motors go real slow they can stop due to worn commutator parts. That usually is resolved by a replacement reel motor.
This is why when I look at reel tables that stop is it motor, idler tire or stuck brake of lack of lubrication. I had a TC-K81 Sony deck that could not play only because the reel table was frozen due to no oul for 40 years. I cleaned and oiled it and the deck then played.

 

[skywavebe]

Also as I was looking at your picture- one more thing came to mind. The belt going to the counter. These counters can jam and cause irregular resistance to the reel table which is yet another condition to consider. I take counters out of decks and clean the number faces with Windex only and then oil the bearing in it as it will become frictional over time. If you use AMSoil in that they turn like a top after servicing. Also in fast wind when they sometimes scream at you as the reel tables do as well, the oiling will stop that from happening and actually increase the speed of the winding. Not as good as a C-1 or Z6000 but better. You can not beat direct drive reel motors. Some of them cost $70 each back in the 80's.

 

[CaptainWins]

Thank you so much for all of your thoughts and expertise! So much to think about.

I definitely feel like I’m jumping to a conclusion as you warn not to do...
but does the fact that the capstan and take up reel are going full bore (to my eyes anyway) all the way up to the moment the autostop is triggered more evidence pointing towards it being the clutch mech.? The intermittent stopping is always preceded (by a second or two) by that white plastic pin just not pushing that pendulum out of the way of the pusher on the worm gear...
I tried again last night to extract that white plastic spring loaded part with the pin on it from reel table but aborted when it was clear I was going to bust it. Is there any chance what i identified as a metal washer in my last post is actually a fiber washer/clutch or were they always felt? It’s very difficult for me to picture where a piece of felt would reside in this part...but what do I know

There is what appears to be a layer of some kind lubrication/wetness between the white part with the pin and the washer. Would trying to soak up a little of that lubrication in the hopes of making it more frictional be worth trying?

Thanks again!


EDIT: I removed the counter as a variable by taking the counter belt off. No change in behavior. Side played for about 20 minutes before autostop was triggered.

Also as I was looking at your picture- one more thing came to mind. The belt going to the counter. These counters can jam and cause irregular resistance to the reel table which is yet another condition to consider. I take counters out of decks and clean the number faces with Windex only and then oil the bearing in it as it will become frictional over time. If you use AMSoil in that they turn like a top after servicing. Also in fast wind when they sometimes scream at you as the reel tables do as well, the oiling will stop that from happening and actually increase the speed of the winding. Not as good as a C-1 or Z6000 but better. You can not beat direct drive reel motors. Some of them cost $70 each back in the 80's.

 

[skywavebe]

Like I had said I have not had one open for a time now. I have one or three CX units here. In some unit there is a nylon part that drives the rubber section of the reel table with a post that is driven by an outer surface part that makes contact to the capstan belt. This is maybe where the felt piece is.If I go looking in my spare parts I think I saw one the other day. The reel table does not always have the felt in it as the torque may be controlled external to it. Look for a part that is that yellow like Nylon plastic that makes contact with the capstan belt that also has a center pin that makes contact to the reel table in play. What I am thinking of might also be a part in the A510 or A550RX type transports.

 

[CaptainWins]

I had to put this aside because it was driving me nuts...but I’ve pulled it back out...still stopping ~2/3 of the way thru a 45min side.

To recap, reel table is cranking away all the way up until deck stops, which leads me to believe the issue is with white plastic press fit clutch mech on back of reel table (which is hopefully still visible a few post up).

Would it be crazy to add some differential oil to make this clutch grabbier/stickier for lack of a better word?

Thank you so much for any help you might be able to offer!!!

 

[spicyvelvet]

I have a CX-350 that I replaced belts on, I bought off ebay for $15 and besides the belts the machine is super spotless! The old flywheel belt basically turned to tar and was stuck to the motor and flywheel. With some rubbing alcohol and time I got it all cleaned up, put on new belts and was doing great. Fast forward a few days. The machine started "chewing" tapes. The reel table for takeup when playing has essentially no torque to it. The capstan, rewind and fast forward all work great and solidly. Could the clutch you mention be so worn that no torque gets applied? How hard is the removal of the reel table for inspection? TIA

 

[quadmatrix82]

I had to put this aside because it was driving me nuts...but I’ve pulled it back out...still stopping ~2/3 of the way thru a 45min side.

To recap, reel table is cranking away all the way up until deck stops, which leads me to believe the issue is with white plastic press fit clutch mech on back of reel table (which is hopefully still visible a few post up).

Would it be crazy to add some differential oil to make this clutch grabbier/stickier for lack of a better word?

Thank you so much for any help you might be able to offer!!!

Did you ever sort this out?

 

[quadmatrix82]

Looking for the felt clutch...I think I’m warm but all I see is an extremely thin metal(?) washer.
Do I need to extract this two part white spring loaded part to get to the felt clutch? And if so how? Feels like I’m going to break something. If it’s not obvious already, I really don’t know what I’m doing, so if you could dumb it down as much as possible it would be most appreciated.
Thanks to anyone who can point me in the right direction.

I tried to pull this apart on my one today could not remove it any suggestions??

 

[quadmatrix82]

Ok worked it out there’s two black tabs you press to lift it out

I see the felt that has been mentioned I flipped it around and cleaned it perhaps that will suffice rather than replacing it entirely?

 

[quadmatrix82]

No success unfortunately before it would play a full tape but now stops after a few seconds

 

[quadmatrix82]

The clutch is on the reel table. You can look at many CX model decks as the mechanism was almost the same. The auto shut off is related to the part that Tony was talking about and concerns the reel table pin in the back pushing a reset arm to the side. When the reset arm is not pushed by a rotating reel table on the right the reset arm being in the middle is pressed on and actuates the stop function. Felt can get dry and some reel tables I have taken apart have like a white powder in them. I don't know if this is from the plastic or the felt glue but just like brake pads the felt does not last forever and needs to be changed. Any kind of felt size can be had from McMaster Carr and even some too thick for a job I have compressed in a vise. You do not have to get the self stick stuff as buying a 12" square piece for a 3/4" round cut out will be a waste unless you work on stuff all the time like me. The reel table assembly is part of the one center assembly so they do not tell you about individual parts on this assembly like reel tables. You need to take parts off of it and examine what part is not working and I would start at the takeup reel table. I have a few CX decks here I can look at. The straight spring I think is part of the pause shut off defeat.

Does this felt washer need to be glued into place? It was not in the one I took apart

 

[quadmatrix82]

success here for anyone in future this might help.

I disassembled the reel table clutch mechanism I found that maybe the plastic has expanded over the years and was stiff to move freely I noticed that hen watching it in play mode it would not move freely like it was binding causing the auto stop to activate at play or fast forward after a few seconds. I cleaned it and added some machine oil and reseated the original felt but swapped its side and now it works well

 

[quadmatrix82]

I have a CX-350 that I replaced belts on, I bought off ebay for $15 and besides the belts the machine is super spotless! The old flywheel belt basically turned to tar and was stuck to the motor and flywheel. With some rubbing alcohol and time I got it all cleaned up, put on new belts and was doing great. Fast forward a few days. The machine started "chewing" tapes. The reel table for takeup when playing has essentially no torque to it. The capstan, rewind and fast forward all work great and solidly. Could the clutch you mention be so worn that no torque gets applied? How hard is the removal of the reel table for inspection? TIA

There’s a few steps involved
Remove the cassette door
Remove the silver back plate where the cassette sits two screws at the top
Remove counter belt
Carefully remove clip holding in the reel table
Pull out the reel table

Try removing all the old grease first and reapply and use fine machine oil for the shaft the reel table sits in and dissemble the clutch and clean and reassemble you may get lucky good luck