If you have a Beocord 3300 cassette deck that has stopped playing tapes or refuses to rewind you may be able to fix it. This post runs through how to change all three belts on the 40 year old Beocord 3300 and restore its musicality!
Warning: Don’t operate your Beocord with the case removed. Always unplug before attempting repair.
Intro
After several years sitting on top of my Beosystem 3300, I found time to plug in the matching Beocord cassette recorder to try and listen to a cassette. There’s no obvious way to open the aluminium flap and gain access to the cassette bay on the Beocord 3300. So if like me you have forgotten, just press the left hand front trim, next to PROGRAMMING, and magically it will open — it doesn’t need power, like the Beogram 3300, as there’s no motor drive for the flap.
Having inserted a good cassette, unfortunately all I could hear was a thud, thud, clonk and no movement.
Some cassette decks are easier to service than this Beocord 3300 from Bang & Olufsen. Designed by Jacob Jensen in the late 1980s, the Beosystem 3300 offered futuristic styling and a change from the uniform 43cm black box stacks that graced many hifi enthusiasts shelves.
Unlike Jensen’s earlier designs, the 3300 is essentially a plastic case with aluminium panels and trim. As such it needs many fixings to join the upper and lower sections — so prepare some lids to collect the screws and note where they are used.
Replacing the belts
To access the belts, first remove all the fixings from the base and two at the rear. There’s no need to undo the two fixings nearest the heatsink. Next remove the plastic base cover. You should see the two drive belts attached to the motor pulley. The larger flat belt had detached on mine, as shown below.
Unfortunately, it’s not possible to change both without removing the cassette mechanism. And the third belt is hidden on top of the cassette mechanism, so you must remove the top cover and lid by undoing the 4 fixings inside.
Once the top is removed there’s a small, thin belt on top of the cassette mechanism which is simply to replace. I found a 25mm diameter, 1mm square belt from an assortment pack that stretched slightly between the two pulleys. Be sure to clean off any goo if your belt has melted, as many do. I use isopropyl alcohol or try hand gel sanitiser if you have no IPA.
The cassette mechanism, located on the right hand side of the unit is held in place by another set of 3 screws. All must be removed to access the lower plate that retains the flywheel. Underneath there are two belts, a 1.5mm square drive belt for the reels and a longer 4mm flat belt for the capstan’s flywheel.
Using a wire hook the square belt is fairly easy to change. Note the route is rather odd, as shown below.
The flat belt goes around the flywheel so you need to undo both fixings that hold the lower bearing. I loosened one end and removed the other to tilt the plate giving enough clearance to slide the belt under. A 135mm long belt seemed to provide enough tension without applying too much force on the bearing. My original belt had disintegrated – stretched with fractures in two places – so I found the right size replacement from an assortment.
You may well decide it’s better to order a replacement belt set for the Beocord 3300. I have done this in the past with mixed results and so I prefer to select the size from a universal set – see links below for suggestions. These are typically available in sets of 50-100 so there’s a good selection for multiple players, especially useful for the local Repair Cafe.
Results
Before the belt change my Beocord 3300 had been covered in letters and papers acting more as an in-tray than vintage tech. Now it’s singing again and sounding rather good. With an HX pro head and fully automated via the remote control, having a working cassette recorder as part the Beosystem 3300 adds to its overall versatility.
Cassettes have become popular again so it’s worth dusting off these vintage machines and listening to them again – who knows what nostalgia it will bring?
Good luck with your repair and please leave a comment if you find it useful.
Useful links
- Beocord 3300 Service Manual – https://beomanuals.com/manuals/Beocord/Beocord%203300/
- Amazon Universal Cassette Belt set – https://www.amazon.co.uk/Cassette-Biluer-Universal-Recorders-Machines/dp/B088PFRM96/
- Replacement belt set – UK eBay – https://www.ebay.co.uk/itm/174357398829
Postscript
Increasingly I’m finding AI’s large language models are using (stealing) my content to provide answers directly in your browser. It seems good for you but ultimately bad for me. Why?
While I run this website to help others repair and fix items to avoid throwing them away, it takes time and effort to research and write. I welcome and need the feedback and questions that helps share how others encounter issues and helps improve the content for all.
Comments and feedback have all but ceased since the integration of AI search. So I ask myself why bother? Ultimately, just like many creatives and artists AI has ‘learned’ (stolen) from I think we will simply stop publishing on the Internet. And AI will then have to feed on itself and we all know what Darwin thought us about incest.
In effect, the AI industry has become valuable by using Internet content for free. Without consent or any renumeration to its creators. It’s wrong in so many ways and I guess ultimately the AI industry will have to pay one way or another. The backlash will come – just as it has for many technical revolutions.
But until it does this is the last post from Radio Retro.
11/05/2026 at 12:17 pm
Hi, is it better to buy original replacement belts that come the right size?
11/05/2026 at 2:53 pm
It’s your choice. B&O did supply original belts for their older models but AFAIK they are no longer available for vintage items like the Beocord. I can recommend https://www.dksoundparts.com for compatible parts, although they are not original. This way you know they will be the correct size. Keep in mind if the belts were original they will have aged and unlikely to last long. So I would prefer a newly manufactured belt if it’s good quality.
06/09/2026 at 1:59 pm
Great tutorial, just used it to change the belts on my Beocord 3300.
Unfortunately, it still doesn’t seem to want to play! I’ve re-checked the routing of the belts but although idling on powering up and allowing me to select play/ffw/rwd it will only operate each function for a second or so. Any thoughts?
06/09/2026 at 6:29 pm
Seems likely auto stop is being activated causing it to stop. Try operating it without a tape so you can check the take up spindle (RHS) rotates and pinch roller operate in play mode. Check the rewind (LHS) spindle as well. If they both spin without stopping try gently touching the spindle to check it has sufficient torque. If it stops turning and cuts out it’s possible a belt is slipping and can’t provide enough torque to drive the cassette tape – try a slightly smaller diameter belt. If it stops without a tape and the take up spindle spins there’s a fault with the auto stop circuit (Hall sensor).
07/09/2026 at 4:26 pm
I managed another quick look this afternoon.
Both spindles turn on play, capstan and punch roller too. I can stop the spindles with finger pressure though, despite the new belt. With a cassette in place, it’s almost as though the tape is being over tensioned/ locks up in play or ffwd mode, but goes loose in rewind. No actual tape chewing, but it did unspool inside the cassette.
Thanks for the advice so far, I’ll keep investigating! CD 3300 next…
07/09/2026 at 6:42 pm
That’s interesting, the take up spindle on mine keeps rotating when pressed between finger and thumb – so worth checking if the small belt on top or the square belt below is too loose. When I checked my Beocord I found the cassette wouldn’t operate properly every time – it kept jittering on play and stopping after rewind – I feared mine had developed a similar fault. Turned out to be the spindle not engaging properly when loading a cassette. It appears to be because the take up reel brake (clutch) is engaged when stopped and this makes it difficult when loading a cassette to get the sprockets lined up. Just mention this in case your Beocord is misbehaving too.
07/09/2026 at 7:10 pm
Good luck with the CD3300. The mechanism is fun to fix as you will see – https://storycase.co.uk/radio/bang-olufsen/beogram-cd-3300-capacitor-fault/. Recently both the 3300 and the CD in the Beocenter 9000 refuse to play unless the swing arm is moved gently away from the centre with a careful prod, avoiding touching the lens. Seems the transport becomes sticky if not used for a short time, something I’ll investigate when I get time.
07/09/2026 at 7:41 pm
I only picked up the Beosystem 3300 a couple of weeks ago. The older gentleman I got it from was adamant the CD was working that morning, but it wouldn’t read a disc when he was demonstrating it… No question mark display though, so hopefully something reasonably simple!
I’ll try a different belt for the spindles. I’d gone for a ‘kit’ for simplicity, but do have a bag of belts bought for previous projects that should have something suitable.
07/09/2026 at 9:22 pm
Worth persisting, the Beosystem 3300 has a nice sound and the touch sensors and leds add to the retro style. Yes, if there’s no error ? displayed, try checking the optics are clean and the laser arm moves freely. I suspect the 33uF capacitor will need replacing at some point. I find kits are hit and miss, so have bought several mixed bags to select from. Unfortunately most bags only contain thinner 1mm square belts rather than the 1.2/1.5 B&O and other manufactures used. These still function, but maybe won’t last as long or more prone to stretch.