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Hi,
I am currently restoring my first Beogram.
I have cleaned the two bearings in acetone for about 24 hours. Thereafter the bearings has been re-oiled (infused in vacuum for about 48 hours (until bubbling stopped)). Furthermore I have change the drive belt and idle wheel due to dried out rubber.
The turntable is running very silent and smoothly but unfortunately it is still running slow (26-29 rpm). Is this the time where I should just give up, or is there anything else to do? Any sort of adjustment in the mechanics maybe?
Any help is much appreciated.
Hi and a happy new year
If the platter is still slow and you have made an oilinfusion and new belt, idler wheel and so on there are only two possibilities:
1 Motoraxle or bearings misaligned.
Are the bearings same size or one smaller and one bigger? I don't remember in the moment.
Motor runs out slow if mains AC is cut?
2. Misaligned stepped pulley part No. 200 (too near to the motor)
Switch to 45 and with the alignementscrew for speed variation far down until stop.
The stepped pulley from motor away until the idler wheel part 210 starts making noise.
A little back to the motor until noise is gone.
So you have the maximum possible speed adjusted.
i wish you success, and let us know
Best regards
Christian
What Christian said.- Or it could be a 60Hz motor running on 50 Hz mains.
Martin
@Spassmaker
Thank you very much for taking your time! Much appreciated
1. Can anyone confirm if this bearings are the same size or not? I did not notice any variance and definitely does not feel like dissemble the motor again if not nessecary :)
2. I guess you are referring to section 4-3 (Step-cone pulley) from the service manual and I'm pretty sure this is the problem. However I'm having troubles fully understanding that section and I'm definitely not convinced that I'm doing it right. The step-cone pulley is around 5mm from the motor as the manuel suggest but I'm confused about how I configure the maximum speed.
One time the speed went to 32,4 so I guess i did something right. Configuring again the speed went down. Tells me I have no idea what I am doing when configuring the adjustment wheel.
This might be a stupid question but what's the starting point in this configuration. Should I work with the turntable up-side-down cabinet off or do I somehow have to work from below cabinet off? belt on or off?
Hi
Please take of the platter.
On the left side you will see your pulley.
The stepped pulley has a bigger diameter as much deeper the idler wheel runs on it, so the idler wheel spins faster as more you align the stepped pulley in vertikal direction to the top.
if you switch between 33 and 45 the idler wheel goes up and down.
on 45 it's in the lower position on the bigger diameter of the stepped pulley.
While the motor is running with adjust the speed adjustment wheel on the left outside and bring the idlerwheel down to it's mechanical limit.
shut of motor adjust the stepped pulley as high as possible so it works without making noise because the idlerwheel is running on the lowest edge of the stepped pulley.
Start motor an listen.
Rubbing noise stepped pulley deeper
No rubbing noise stepped pulley higher
Don't know how to discribe in other words ;-))
Good luck
Hi again,Spassmaker, thank you so much for your time and explanation. It made perfect sense!I've configured the idle wheel and am now able to start the turntable at 33,3 rpm! Wuhu so far so good! HOWEVER.. I am having troubles maintaining that speed. The turnable speed varies from 32,8 to 33,5, then back at 33,3 for a while.
For now I am happy with the result but will get back to the project another time!
Again, thanks a lot for the help.
EDIT: Meant to write stepped pulley not idle wheel! "I've configured the stepped pulley...."
I have had this problem on a few BG120x and BG3000 TT's.
The solution was to carefully disassemble the Voltage Selector switch, and clean off the oxidization from all the brass selector contacts.
Wipe gently and repeatedly with cotton wool dipped in Brasso, or similar Metal Cleaner.
Definitely do NOT sandpaper, or file the contacts.
Afterwards, spray correct Electronic Contact Cleaner (Kontakt 60), and Reassemble.
Be careful to not lose the tiny spring, or ball bearing.
M Yachad