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This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi everyone
I have a Beogram 4004 - she's beautiful but old, and has a few small problems. im struggling to solve one of the issues:
The tone arm does not lift fast enough when either moving the tone arm using > and < buttons or when ending play. It means that the needle is dragged across the record for a second as the tone arm moves and lifts at the same time. I've lubricated all the parts around and below the tone arm mechanism (at first the tone arm wouldn't always drop either - this problem seems to have disappeared).
any thoughts or suggestions?
Steve
Hi Steve,
I've got the same problem with my 4002 but so far haven't found the cause. I've removed and cleaned the solenoid/damper mechanism and refitted in accordance with the service manual, ensuring the correct distances between arms etc but the problem is still there.
It seems like there's too short of a time gap between the solenoid activating and the arm motor engaging - either the solenoid engaging too late OR the motor engaging too early.
It's annoying!
I think this is due to the magnet coil return spring.This is the one to the right of the coil.
When the coil is de-energised,ie when you press the raise key,there is a residual holding field that needs to be overcome by the spring.
When you think about how many times the spring has been stretched over the years,it's not surprising it's lost some tension!
I spent some time "getting technical" over this,before the most obvious culprit was identified.
Regards,
Nick
Thanks Nick. Any easy remedy? What was your solution? Are these springs even available?
I bought a box of assorted springs and experimented with tensions.You need to get something that will be strong enough to return the the magnet coil lever/arm,but not so strong that arm lowering is impeded.
Alternatively,the ever helpful Dillen via this site,may have a salvaged spring?
Hi
this has to do with the coil, but it's the lubrication, that's got hardened and not a worn out spring. You have to disassemble, clean and grease again.
Chris
solderon29: When the coil is de-energised,ie when you press the raise key,there is a residual holding field that needs to be overcome by the spring.
No, I think it's not. It's powered, when the arm is in play position. Otherwise the tonearm would lower down, when unpluged from mains.
Check youtube https://youtu.be/IxIxHb8sZdg
Thanks guys - the problem is more serious than I thought. Update:
The damper seems stuck - despite having cleaned it out and lubricated. It is very difficult to move.
The stuck damper has hindered movement and as a result BENT the top horizontal arm that connects the solenoid to the damper across the top (because of this lack of play)
In the process I lost the c-clip. I'm usually good at this, but today was not my day :(
How to proceed here? Do I need to source a new damper, and arm? Are they available.. Or repairable??
(Help.)
steve
The solenoid can bend none of those arms.
The swivels can stuck as well. Did you watch the video?
I don't think it's a really serious fault. Everything is very solid.
Steve: In the process I lost the c-clip. I'm usually good at this, but today was not my day :(
Perhaps you can use a small piece of shrink tubing.
Thanks ProGram. I did watch the video. Swivels seem fine and have been luvricated - I'll take a pic of bent arm and post. How to get the damper going again?
Just to clarify - it was the damper that bent the arm, not solenoid
Steve, I am not an expert here, so be cautious with my advice.
I have the same Beogram and had the same problem with the damper.
After cleaning and lubricating I adjusted the damper speed with the little screw (in the right bottom corner of your picture).
The screw with the red laquer on it.
I do this from memory and it is about 10 years ago I did it, so I am not 100% sure.
Besides this link to maintenance of the solenoid and damper - video from Beolover (same as the YouTube one mentioned above), you should also look at this video on the Beogram 4000 about a seized solenoid and tonearm linkage. It is very similar on the Beogram 4002/4004.
-sonavor
Steve: Just to clarify - it was the damper that bent the arm, not solenoid
Ok if you think so, but keep in mind that the damper is no active part. But you are right: the arm is not in the right angle. It should be straight (more or less), when you look from above.
Maybe you use a grease, that is too sticky. Can you clean again and try a different? And "play" with the little screw at the end of the damper.
ProGram: Steve: Just to clarify - it was the damper that bent the arm, not solenoid Ok if you think so, but keep in mind that the damper is no active part. But you are right: the arm is not in the right angle. It should be straight (more or less), when you look from above. Maybe you use a grease, that is too sticky. Can you clean again and try a different? And "play" with the little screw at the end of the damper. Chris
I don't see how the solenoid, connected or not connected to the damper, would have the power to bend metal like that. The solenoid is not that powerful and the damper is just a small amount of compressed air to delay the arm lowering by about a second. It had to be bent at some point by a human. I'm not accusing you of doing it but someone had to have bent that metal bar in the past (accidentally or not).I would recommend removing it and trying to straighten it. Then go through the adjustment procedures the Beolover videos describe. Make sure all of the moving components (including the tonearm raising and lowering lever) all move easily by hand.-sonavor
Perhaps the air hole of the damper (adjusted with "that little screw") is completely closed. The damper certainly won't go around bending metal parts...
--mika
Thanks all - i'll try bending and re-look at the damper. I tried to turn the screw on the back, but it's stuck tight. Any advice on how to loosen?
Which screw? Can you post a picture of it?
Here is a picture of how the solenoid would engage to lower the tonearm. The solenoid has a push/pull rod on the opposite end of where your bent lever is. When the solenoid engages it pulls that lever forward. You lever is bent the opposite way which is the direction the solenoid would travel when it is released, no power. That direction just relies on the springs.
To remove the bent lever you need to pull out the damper. It is just attached by two screws and the two big springs. If you remove the two screws and the two springs the lever should pull off its pivot post.
Once you pull out the damper and lever you can repair it. Then you can also check the damper valve screw. This one is from a BG4000 and has blue locktight on the screw. Yours has red. It should break loose when turning the valve with a proper, long barrel screw driver. You could try and scrape away some of the locktight first.
While the detector arm is off you need to check that the movement of the tonearm release lever is not stuck. I usually remove it, clean and lubricate the pivot.
sonavor: I don't see how the solenoid, connected or not connected to the damper, would have the power to bend metal like that. The solenoid is not that powerful and the damper is just a small amount of compressed air to delay the arm lowering by about a second.
I don't see how the solenoid, connected or not connected to the damper, would have the power to bend metal like that. The solenoid is not that powerful and the damper is just a small amount of compressed air to delay the arm lowering by about a second.
That's exactly what I'd said. I didn't know, that the deck is a second-hand.
Hi guys
firstly, thanks for all the help with this.
I've managed to straighten the arm - pic below. I've also lubricated the damper.. I just can't get the setting right. It just seems to pull the rod and spring at the top without any valve movement (regardless of position) and the tone arm bounces down. Perhaps I damaged it in the cleaning process?
also - the C-clip for the bottom pin... Easily replaceable? The lever jumps out ocassionally, so definitely not something I can ignore.
When stylus dropped:
The lever does look straight and correct now. On your damper and tonearm lowering problem, it sounds like you have a problem with the distance where the damper piston pushes the tonearm lever. Here is another picture.
After you get the solenoid and tonearm lift lever parts cleaned, lubricated and working correctly...the tonearm will still need all of its adjustments checked using the service manual procedures. At the back of the tonearm there are adjustments for the balance, set down height, parallel and vertical height. You will need to make those adjustments so the tonearm can move properly. But the work you are doing now must come first. The Beolover Blog has plenty of information on these adjustments and you will find plenty of pictures on my Beoworld thread. Just be aware that there are a lot of adjustments to make so don't rush it.
Regarding missing "C" clamps. You will have to measure the diameter and order a replacement from a hardware store (maybe Amazon has them). You can continue the cleaning, lubricating and adjustments without that missing "C" clamp for now. Just don't forget to add it before you wrap your project up.-sonavor
Thanks Sonavor. The tone arm lift is moving freely and without issue. The problem is, that the damper seems to have too much play initially.. So it shoots as fast as the solenoid does, despite closing the valve. However what is moving is the long metal link out of the damper and spring without the valve moving much.
Have you taken the damper assembly apart, cleaned and lubricated it? Here it is fully apart. After reassembly (and before re-installing it). I check that the damper valve screw works to control the piston operation. Then I usually set it to a position where it moves pretty easily. During final tonearm adjustments of the turntable I set the valve in the proper position to control the tonearm lowering speed per the service manual (about 1 second).
I have - the screw for the valve however seems stuck in one position, turning aimlessly in the plastic. Salvageable ?
It sounds like the threads might be stripped in the plastic valve case. You will probably have to get a spare valve case. Someone on the forum might have an extra one. I'll check my stock. In the meantime you will likely have to try to repair it. A repair option would be to seal the screw hole and re-tap it but that is tricky in this case because the hole must also allow the tapered end to open and close air passage. Before you try that I would wait and see what other Beoworld experts have to say. They may have an easier solution. Maybe try a little Teflon tape around the valve screw threads.
Thanks for all the help. I'm fairly good in this space but repairing the case may be beyond my skill level. I still don't understand why the damper has so much 'play' on its spring. If you have a space damper case I would be extremely grateful -parts seem non existent.
I thought of something else. The damping valve screw mounts onto the black plastic piece that attaches to the brass damper case. Maybe that black plastic piece is loose and doesn't seal. Does the screw feel like it screws into the black plastic threads okay? If it is indeed, not stripped, then the problem must be due to some air leak somewhere else in the assembly. You may only need to find and fix the leak.
The screw feels quite stiff in the black plastic piece, and when I took the valve out I noticed black 'dust' in the chamber. Perhaps pieces of plastic from the black back end. Can the leak be caused by metal pits or knocks on either the valve or casing?
Black piece seems attached to the brass case. I wish I was able to post a video
Looking at the back of the damper, you can see the valve screw going into the chamber to control the air flow. If you block that rectangular opening, does the piston then have resistance to movement? If you haven't done it already, I would take it apart as in my pictures and get a better look at everything.
I have trouble following this. On the first page, you tell that the damper doesn't move at all, and now it suddenly moves freely and doesn't damp at all?
Hi Mika
What's happening is:
The big damper valve isnt moving in the chamber, but the rod coming out of the damper (which holds the damper's built-in spring) seems to pop out extremely fast and drop / bounce the arm down.
What you call a damper valve is a damper plunger, the adjustable air valve is there to get the plunger move slowly out of the cylinder. The plunger shaft is moving inside the plunger, the plunger shaft has an air relief valve attached inside the plunger, if this air relief valve is damaged only the plunger shaft will move, take your damper apart as in the pic and check inside the plunger.
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