Absolutely first thing is to ZERO balance the arm, and that's done with the stylus/cartridge installed. The procedure is shown MOST clearly in the BG1202 / 3000 Service Manual. IIRC, around pg19.

After you've zero balanced it, set the cartridge weight to 2gr. Then on each subsequent LP play, reduce it by 0.1gr, until you find the sweet spot for your cartridge, which could be anywhere from 2.0gr to 1.2gr. 

Well, the 1203 is back from a random chap I found via ebay who lived quite close and it works like a dream!

I'm still unsure what Rex Radio really did when they repaired it because the spindles look like the original ones. This new chap found the problem with the return too, the DIN had been replaced with RCA's and the cable, although a good one, was very stiff so wasn't letting the arm move quite as freely! He replaced that, put in a proper earth cable, and oiled the motor all for £25 and now it's playing beautifully!

He said some bushings or springs or something were close to worn out which results in the motor sitting a few MM lower than it should so the speed dial on the side has to be cranked to max rot achieve the correct speed... but... it works.

Next up, the 1200 and those awkward little parts!

Works like a charm!

[View:https://www.youtube.com/watch?v=wYzxosWQhS4:800]

[View:www.youtube.com/watch?v=wYzxosWQhS4:800]

https://www.youtube.com/watch?v=wYzxosWQhS4:800

Unlike the video embed option on here...

I have a BG3000 - 1973-model radial. Beautiful machine, which I've serviced many of.

But here I have a problem, which I have never seen before.

Common problem - it came in with a non-working motor. My normal procedure is a complete cleaning, oil and shim the motor.

That solves the problem on all the 1202's, 1203's and 3000's, which I've previously done.

I've checked all connections, replaced the diode and capacitor inside the relay, cleaned all contacts.

I disassembled the top and bottom bearings of the motor, removed the old felt discs, put in new felt, didn't help.

But this one - forget it. The motor barely starts rotating, very slowly, and then the slightest pressure from the idler wheel stops the motor.

It's as if it just doesn't have enough juice. Any ideas?

Is this an issue with the BG1202 / 3000?

If not, does anyone have a spare motor assembly, preferably from a 1203?

Menahem

Typical sign of a motor that has been allowed to run with dry bearings (hardened lubrication).
The pores in the bronze material are extremely delicate and soft. Under normal circumstances there
are no direct metal-to-metal contact from the motor spindle to the bearings because the parts have a very thin
film of oil between them, which also minimizes friction and gives a practically endless bearing lifespan.
However, if the motor has run with wrong -, dried-out - or no lubrication, the spindle will have touched the inside surfaces
of the bearings and the bronze material will have been smeared out, closing the microscopic pores in which the
lubricant sits and flows.
One-phase AC motors of the short-circuit type like this has very little initial torque so gathering speed can be very difficult even
with good lubricants and, needless to say, almost impossible with no lubricants.

It's a common problem with all decks using one-phase AC motors, Beogram 1000, 1001, 1200, 1202, 1203, 2000, 3000 etc.
and it's also very typical to see the motor running and working perfectly right after servicing but a month or so, sometimes just
a couple of days, later, it will again be very difficult for it to gather speed.

The only lasting fix is to replace the bearings.

- And please upgrade to a minimum membership level of silver to place wanted ads.

Martin

Thanks Martin

So, If I was to lightly sand the inside of the bronze bearings with rolled-up 1000-grade water-paper, would that be a good solution?

That would almost definitely destroy them.
It's a very soft material.
Besides, the inner diameter would end up being too large so an oil film cannot build up and that
is immensely important.

You know from shimming up the motor spindle, that it's very important for the spindle to sit exactly aligned
in the bearings. The tiniest amount of skew and the motor spindle won't run freely enough, that's because an
oil film cannot build (and/or it runs metal to metal on the upper or lower edge of one or both bearings).

I am currently working on a solution to this bearing problem and I will probably need volunteer testers - if you are patient....

Martin

Only too happy to help!

I'll look at SKF or other bearings to see if they have a ready made roller bearing solution to fit inside the B&O race, or have you already done that?

I think the friction is far too high in ball bearings but, by all means, go ahead and try.

Martin

I have had the same problems with my BG 1202, and when I get my BG 1000 over here, I will try with Nylon bushings, I have with success used a product called Nylamid XL, in small electromotors (well bigger than the BG motors), its a polyamide product containing MoS2, and used for self lubricating bushings.

Will be back with more after tests.