[Mark-sf]

The arm should be in the recording playing mode and then the weight should be adjusted to zero tracking force. Then you rotate the numeric dial without moving the weight so that zero is a 12 o’clock. At that point you rotate the entire weight to the desired tracking force.

[Mark-sf]

I would try injecting a signal at the wiper of the volume control for each channel with the volume at max and then take your distortion measurements. This will pinpoint whether you have an amp or preamp issue. I’m betting on the latter from your discription.

[Mark-sf]

A relay’s contacts can corrode over the decades especially when not hermetically sealed. This introduces a variable resistance which causes the speed variation. One can affect a temporary fix by carefully cleaning the contacts since the cover is removable; however, this is only a temporary fix and its very easy to bend the thin contact supports making it worse.

[Mark-sf]

You most likely need to replace the speed switch relay. There are modern replacement kits available on eBay or Beolover’s site.

[Mark-sf]

Yup need to do some measurements instead of using your ear to answer my questions. Download a turntable App for your phone such as RPM and come back with answers to 3 and 4.

[Mark-sf]

Worn bearings would not cause a motor to run fast. I would approach diagnosing this in this way.

1. Determine if the speed is fast for both 33 and 45.
2. Determine if the speed is faster for 45 to the same extent as it is for 33.
3. Determine what specific speed range for 33 and 45 you can adjust over.
4. Determine whether the speed is steady even though fast.

From the answers to the above, one can pin down the area of the system causing the problem. Feel free to post these and I’ll give you my diagnosis.

[Mark-sf]

First, confirm all of your springs curl up when the sub-chassis is unhooked. Then you use the rear nut to bring the sub-chassis high enough to float between the lower and bottom stops. Then tweak the three nuts to ensure the platter is level but not necessarily even with the top plate. If you then need additional height, you can loosen the locknut on the center bearing and raise that as it is threaded. You will then need to make sure your arm cued-up position will still clear the record.

As to centering, there is some side play in each leaf spring and you can also get some side or front/back play by slightly bending the rear height screw. I have never seen the need for more than 1-2mm of adjustment. If you do then look at your top plate alignment as that is likely out.

[Mark-sf]

I have never seen the leaf springs fail. I have seen the plastic inserts break down and leave pieces interfering with the suspension. I would carefully examine the transport screw mechanism for these. When I do a referb of either 400x 0r 6000 I remove the entire sub chassis to clean out the pieces left behind. If you do remove the transport screw assembly be careful of the multiple washers and there orientation and ordering.

[Mark-sf]

Take a look at the 2200 schematic at https://beomanuals.com/manuals/Beogram/Beogram%202200/Bang-Olufsen-Beogram_2200-Schematic.pdf. It provides all that detail.

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