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Repair Technics M255X Cassette Deck (Tape speed is too fast)

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PieterDV:
Hello, 
I bought on the internet for my daughter a beautiful vintage Technics Stereo.  There was some work to do.  So I have fixed the mechanism of the SL-10 turntable.  Fine-tuned the FM tuner (ST-S505L).  Repaired/replaced a connector from the speaker connections of the SU-V303 amplifier.

But I am not able to fix the Cassette Deck.  It is a Technics M255X.  The tape drive is running MUCH TO FAST in play mode. The belts are OK. The pressure wheel (I don’t know the correct word in English) is OK (tested by slowing down the big heavy wheel (sorry, no idea in English) .  The motor is simply running to fast.  I found the “Tape Speed adjustment VR” in the service manual but this is not influencing the speed at all.

Another thing that I see is that when you press EJECT the tape playback is not directly stopped.  Maybe this is related ?

Note also that the tape drive was not used anymore for many years, but was stored in perfect conditions (living room).  The old lady (husband died a few years ago) was not aware of a technical issue with the deck.

Can anyone put me in the right direction to solve this speed issue?

Many thanks in advance,
Pieter (Belgium)

MacGeek:
Hi Pieter,

Your description suggests the motor capacitors may be out of specification and need to be replaced.  Unless you are electrically inclined, this is usually a job for a technician.

Sir Thrift-a-Lot:
Motor caps were me first thought as well.

PieterDV:
Many thanks for your help here!

So I have opened the motor and removed the 2 capacitors.  It is one of 10 uF and one of 3,3 uF.  I have checked them with my Tektronix DMM254 multimeter and have the values :  11.00 uF and 3,46.  So this is OK or not ?    ...I can check  those things but I am not a specialist/Engineer. What do you think ?

OldiesButGoodies:
Hi Pieter...

As Macgeek and STAL pointed out, that speed issue is often related to the motor caps.   I note that you used the VOM's capacitance function to test them.   Can you also use the VOM's resistance function to do a few more tests on them?  After discharging each cap (just short the leads with a wire),  measure resistance - what value do you see?  does it show any value?  does it start with a low value then go to infinite?

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