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A small amount of teflon-based “oil”.
A seller on Ebay once had something called “liquid bearing”, that’s very good.
Because it’s not really an “oil”, but mainly microscopic teflon balls, it doesn’t really
evaporate and it doesn’t grab and hold dust and dirt the same way an oil will.Don’t use shaver- or sewing-machine oil. It evaporates over hours rather than years, and
most will leave some of its additives etc. behind.Forget WD40. Keep that in the garage for use with rusty cars.
Martin
So was I.
Martin
Check the three large filter capacitors.
Martin
It’s my impression, that Multicare is one of the best places, you can send your Beogram.
The trim will be replaced as part of Bang & Olufsens Classics Recreated programme to reflect that, after 50+ years, it was rebuilt professionally.
(Using good quality parts).I wouldn’t worry.
Martin
Blown fuse and/or ripple on power supply DC voltages from bad filter capacitors (the three large cans).
A scope will tell.Also, if present in your Beocenter, check the capacitor on the edge of the CPU board. It’s known to short.
Martin
If you are sure the belt is correct and not something off Ebay or similar, lubricate the motor bearings.
Martin
I doubt you can find someone selling parts for this particular model, but many electronic components are fairly standard.
Which parts specifically are we talking about?Martin
The two screws can be accessed from below at an angle, through holes and passing boards etc.
Martin
Check the motor phase adjustment.
Martin
When in 45RPM, does the motor pulley vibrate if you feel with a finger, or is it completely still?
Martin
Use a puller.
Grab under as close to the spindle as possible, not to bend the copper plate.
It’s easily distorted.Martin
Perhaps a bad capacitor somewhere. That wouldn’t be a first.
Put a scope to the signal path, compare left/right and see, where the signal is lost.Martin
Unless the spindle runs VERY freely by hand (read: run down 5-8 seconds or more), it will need service.
Yours will, by the sound of it.Martin
Grease won’t do.
It has to be an oil, and it has to be light, homogenic and “self-dissolving”, and of course have the right properties and additives.
A mix of primarily SAE30 was used originally.The bearings from Beoparts are pre-oiled, ready to fit. So are the felt washers.
Just clean the spindle using IPA and a clean lint-free cloth.
And then keep the spindle clean. Leave no fingerprints on it afterwards, – there is no room for any.With the motor reassembled, you may need to align the spindle and bearings axially, or one or both bearings may end up running on “edges” instead of parallel on their plain inner surfaces.
Originally there was a tool for this task (not a very good one, really) but moving the spindle
around, pushing it sideways a little and rotate it by hand, paying attention to
the run-off time, will give you an idea of the sweet spot.Martin
Perhaps not that exact product, but I know a thing or two about sinter bronze bearings,
and I have had my hands on lots of things with names beginning with “super”.
I remember one product was advertized for use with space shuttles, for which I’m sure it will be fine.
But I threw most of it away. It didn’t do anything near what I wanted it to.
Now I think of it, perhaps it was because I didn’t have a space shuttle to use it with.Anyway, – if it has teflon or similar modern “floating”/”suspended” stuff, that gets pressed in to the pores in the
bearing material, cluttering them, it’s usually safe to deem it no good for sinter bearings.
And very difficult to remove from the bearings pores again as teflon and microplastics are not easily dissolved. At least not without leaving a mess behind.Martin
You need to take the motor out. Undo the three springs etc.
Then remove the idler wheel and pull off the pulley.Martin
I just edited my above reply to be more specific.
The felt washers are oil reservoirs sitting around the bearings.
You will see when you take it apart. (Yours will have hardened or at least run dry).
It’s a special technical felt material meant specifically for this purpose.
The bearings pull oil from the reservoirs to replenish and compensate for what is being used.Martin
Just adding oil in “free form”/ as drops, won’t provide a lasting solution.
It will be pressed away as the motor runs.
And only few synthetic oils have the right additives for running with the metal alloys used here anyways.The bearings are sintered. They will need oil infused into the pores in the
metal material from where it is pulled by capillary action when the spindle rotates.
Reoiling can be difficult seeing as the remains of the old oil needs
to come out first in order to infuse new oil.
Best and easiest is to replace the bearings altogether.New bearings here, correctly oiled.
Your bearings may – or may not – have an additional flange, which is of no practical importance here.
Martin
Have you checked the fuses?
Martin
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