Thanks again for the advice.

I built a small vacuum chamber using a hand pump vacuum brake bleeder and a 1/4” brass nipple epoxied into a mason jar lid. It held -25 inches of mercury for 16 hours until bubbles stopped coming out of the bearings. I used a sewing machine/spindle oil. 

Beogram is back together and running well. I just hope it continues to do so this time. 

I played the Beogram 3000 again last night, and according to the strobe, it is still running slow at startup (when cold) but speeding up gradually over the first 15-20 minutes. I have read that this was a problem even when the motors were brand new - is that correct? Has anybody found a solution other than motor replacement? 

The my ear, the speed is steady and consistent from one moment to the next, but over time it definitely speeds up considerably. That's a little annoying, but I guess I can live with it if, after warm up, the speed does not change. I can always adjust the speed for warm running and wait several minutes before using. 

Wrong oil.

The motors were fine when new. Where did you read anything else?

At some point B&O issued a tech note about their stock of replacement motors getting old (decades), and that they could no longer guarantee, that the
motors would run out of the box without servicing.
That was because their replacement motors was produced at the same time as the Beograms in which they were used, and the oil in the bearings dry out regardless of use.

Martin

SAE30 is the grade of oil used in 4 stroke lawnmower engines like Briggs and Sratton. It is available from garden maintenance or lawn mower repair establishments in quite small quantities.

Modern SAE30 could of course contain the wrong additives for the Beogram motor bearings.

Dillen wrote:

Wrong oil.

The motors were fine when new. Where did you read anything else?

At some point B&O issued a tech note about their stock of replacement motors getting old (decades), and that they could no longer guarantee, that the
motors would run out of the box without servicing.
That was because their replacement motors was produced at the same time as the Beograms in which they were used, and the oil in the bearings dry out regardless of use.

Martin

I respectfully disagree. I started with 10w30 synthetic oil (Mobil 1, actually). At normal operating temperatures, it's characteristics should be identical to SAE30, except that it is less viscous when cold. The motor did not run well for long. I am willing to admit that the oil could have been too thick, and that I did not get enough into the bearing. 

You recommended Mobil Velocite 6 which has an ISO VG of 10 - which is significantly thinner than SAE30 - according to Mobil's website. I found a spindle oil with the same viscosity, and forced it into the bearings and felt pads by applying a medium vacuum for 12-16 hours. I still have a problem with cold start up. 

If you read the posts from "Coffee Phil" on Vinyl Engine (link, , and cetera) you'll see statements such as these:

It's not a question of viscosity.
It's a question of additives.

I see no mentioning of any statements from B&O regarding bad motors, never heard of any myself, it's not in my B&O tech notes collection or
any of the BoMark pages and I never experienced any problems myself during the 70s and 80s.
Not in Beogram 3000, not in any other deck, until oil started to dry out or wear away across the range.
My experience is, that sewing machine oil is good for sewing machines and of no use in sintered bronze bearings.

I'm not sure how long Vinylengine has been around or how much experience the mentioned member has - though it seems on the same page he is also receiving advice on how to do the bearings.

You are free to disagree.
You may also sit with more experience in these matters than my 44 years of collecting, repairing and restoring B&O audio products, but I know what I have been doing hundreds of times and what works every time for me - and I have also done 60Hz units sent to me from the States.

Any Beogram 3000 motor you'lll find today will need servicing.
I have given you my best advice, it seems you insist on trying something different.
I have nothing more to add.

Martin

I used this oil: 

There was indeed a problem with these motors back in the 'seventies when the product was still current,and the bearings were unlikely to have dried out in only a year or so?

One of the "urban legends" was that the motors were designed for 220v use,and so were slightly over run with the Uk power supply at 240v,making the coils overheat and eventually become "tired"This also seemed to happen with some Thorens decks that used similar induction motors.That argument doesn't hold of course for USA models running at 110v,where the motor coils are switched into parallel rather than into series,as with European spec?

We used to measure the cold resistance of the motor coils before proceeding with a repair,just in case this had happened,so as to save wasted time stripping down the motor,and getting a"bouncing" repair later,with attendant stroppy customer!

The motor's were made by Bogen for B&O,and they were/are jolly good when working properly too.

If a re-lubricated motor performs correctly at the right speed,but then gradually reverts to type(slow),then it suggests that the re-lubricating need's extra attention as Martin and other's have suggested.

If it's consistently slow though,it seems as though you have a "bad 'un",and will need to investigate the coils.A member here did have some success rewinding the coils,so it might be worth searching in the archive.

Do you have another Beogram of a similar type,that you could compare motor winding' s with?

I may have a note somewhere of coil readings,I'll have a search,but I may be a "while".

Regards,

Nick

Thanks, Nick! I actually have the reverse problem: motor performs at a near-normal speed as soon as it is turned on, but then speeds up over the next 20 - 30 minutes. I can adjust the speed to 33 RPM when cold, but by the time the turntable has run for a while, it is running quite fast, according to the strobe, anyway. 

I will check the coil resistance. I'm not opposed to rewinding a motor, if I must. Appreciate the perspective. 

The fellow on Vinyl Engine is of the opinion that it is a rotor problem, and has performed some experiments which seem to suggest that, but any avenue is worth pursuing. 

Where did you find the instructions on taking the motor apart?

I have the cover off revealing an armature (?) or something similar in the middle.  However it does not come out, at least I am hesitant to apply any pressure.

Any help would be appreciated.

Jim