I have an MCD7000 that developed a very strange failure while playing normally.
The player suddenly stopped responding to the front-panel controls. After unplugging/restarting it, I could get either a completely blank display or essentially the entire display illuminated, with the transport behaving abnormally.
I initially suspected an electronic/control-logic problem, but after putting the player on the bench and removing the cover, I believe I've isolated the problem to the disc-loading mechanism.
There is an extension spring on the upper disc clamp/lift arm that is supposed to hold the arm fully raised while the tray opens and closes. It appears that this spring has weakened with age, allowing the upper arm to hang slightly too low.
When it hangs down, it interferes with the tray mechanism. The tray does not complete its movement properly and the player can end up in the bizarre display/non-responsive state described above.
If I manually hold the upper arm in its fully raised position, the tray operates correctly and the MCD7000 works perfectly. I can reproduce this.
I've attached photos showing the spring and arm in question (in Philips service manual the part number for this spring is 4822 492 32395)
Before I modify anything, I'd appreciate advice from anyone familiar with the MCD7000 / Philips CD304-family loading mechanism:
I'd rather identify the correct spring rate/preload than simply install a stronger spring and risk putting excessive load on the mechanism.
Thanks for any experience with this transport.
The player suddenly stopped responding to the front-panel controls. After unplugging/restarting it, I could get either a completely blank display or essentially the entire display illuminated, with the transport behaving abnormally.
I initially suspected an electronic/control-logic problem, but after putting the player on the bench and removing the cover, I believe I've isolated the problem to the disc-loading mechanism.
There is an extension spring on the upper disc clamp/lift arm that is supposed to hold the arm fully raised while the tray opens and closes. It appears that this spring has weakened with age, allowing the upper arm to hang slightly too low.
When it hangs down, it interferes with the tray mechanism. The tray does not complete its movement properly and the player can end up in the bizarre display/non-responsive state described above.
If I manually hold the upper arm in its fully raised position, the tray operates correctly and the MCD7000 works perfectly. I can reproduce this.
I've attached photos showing the spring and arm in question (in Philips service manual the part number for this spring is 4822 492 32395)
Before I modify anything, I'd appreciate advice from anyone familiar with the MCD7000 / Philips CD304-family loading mechanism:
- Is weakening of this particular spring a known problem?
- Can someone advise me on this spring specification?
- Has anyone replaced this spring successfully, and if so, what replacement did you use?
- Was there ever a McIntosh/Philips service modification relating to this part of the tray/open-close mechanism?
- Would you replace the spring outright, or is there another adjustment/lubrication issue I should check first?
I'd rather identify the correct spring rate/preload than simply install a stronger spring and risk putting excessive load on the mechanism.
Thanks for any experience with this transport.
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