I recently picked up this Teac A-4010S and replaced the belt. Everything seems to be working fine besides the capstan motor running as soon as the pinch roller is pulled to left, which has cause tape to be ruined after pressing stop or rewind during fast play. Any suggestions would be much appreciated.
Teac A-4010S Capstan Problem
- Thread starter justicoop
- Start date
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The faceplate will have to come off to repair that. The right tension arm is not returning to full CCW position which leaves the capstan motor micro switch closed, or on. With tension arm full CCW, it contacts the micro switch opening it or turning the capstan motor off. Is the pinch roller linkage sticking? That is common as the grease dries out, causes arm to stick.
Clean and lube (oil) the tension arm pivot shaft. The spring may be weak and need another turn to add some tension. It's common for the park position magnet to fall off and need to be reglued to the arm. If missing, it may be stuck to the front of chassis somewhere.
When that tension arm is moved by tape tension CW or to left, the capstan motor will engage. That is normal operation. The pinch roller linkage does not control the capstan motor. If the pinch roller linkage moves freely and drops from the capstan when stop and rewind are engaged, you may have another issue such as excess brake tension.
Clean and lube (oil) the tension arm pivot shaft. The spring may be weak and need another turn to add some tension. It's common for the park position magnet to fall off and need to be reglued to the arm. If missing, it may be stuck to the front of chassis somewhere.
When that tension arm is moved by tape tension CW or to left, the capstan motor will engage. That is normal operation. The pinch roller linkage does not control the capstan motor. If the pinch roller linkage moves freely and drops from the capstan when stop and rewind are engaged, you may have another issue such as excess brake tension.
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rojoknox
Well-Known Member
Greetings from RojoLand!
SCompRacer hit the nail on the head when he mentioned the brakes. There are two microswitches on the brake assembly that if misadjusted can cause that symptom. I ran into that with my A-4010S; just turning the take-up reel while in Stop would cause the deck to start playing. Along with the microswitch adjustment, the brakes have a tendency to get grabby. (I damaged a tape when stopping it — the abrupt stop caused a snatch.) Cure is to replace the felts and readjust brakes.
Take care,
—
J. E. Knox "The Victor Freak"
Current caretaker of A-4010S S/N 48104
SCompRacer hit the nail on the head when he mentioned the brakes. There are two microswitches on the brake assembly that if misadjusted can cause that symptom. I ran into that with my A-4010S; just turning the take-up reel while in Stop would cause the deck to start playing. Along with the microswitch adjustment, the brakes have a tendency to get grabby. (I damaged a tape when stopping it — the abrupt stop caused a snatch.) Cure is to replace the felts and readjust brakes.
Take care,
—
J. E. Knox "The Victor Freak"
Current caretaker of A-4010S S/N 48104
IIRC the service manual calls for a 0-10 ounce spring scale. If you have a gram scale, you just do grams to ounces conversion. 5 ounces = 141.7 grams. They also called for a 7" reel with 4" center hub, 30" of string. Brakes should measure 5.5-7 ounces.
If a 2" hub is used some conversion math will need to be applied.
If a 2" hub is used some conversion math will need to be applied.