Marantz 3250 balance fader problem

[acidtest64]

Hello everyone! I am recently experiencing a problem with my Marantz 3250 balance fader. This unit is very clean, and I've routinely cleaned the balance fader, as well as the treble, bass, and mid faders with MG Chemicals cleaner.

I have also used Deoxit fader lube and fader grease in the sliders at different times with different amounts; none of this makes the faders operate more smoothly, in fact, they are difficult to move.

This brings me to the main problem. Recently the sound has been dropping out on my left speaker. Jiggling the balance fader back and forth eventually brings it back, but it soon goes out again, and I am only getting sound from my right speaker.

Does anyone know what is happening here? Any suggestions on how to fix it? Does anyone know of any other Marantz models that would have balance faders that would fit if I could find a part to replace it with? Any help is appreciated, thank you.

 

[wlhd1610]

You could try carefully taking the fader apart by bending back the tabs and see what is going on inside.
Maybe the slider brush fingers are gummed up or the nylon slide itself is binding.
Hopefully it isn't degradation of the carbon tracks themselves.

It is replaceable if not salvageable.
Pics would help

Bob

 

[Richs_Trains]

I have 2) 3250's and both experienced drop out problems and although I cleaned both the volume and balance controls, it would still happen. Turned out the -20db muting button was the culprit. It's not a bad idea to clean as much as you can reach while you are inside, sometimes it is a control you don't think of and never use.

 

[KutzlerTrans]

I had issues with this esotec balance ans as Rich noted, it was a dirty switch contacts, and being lazy, i took the "push all the buttons in and out twenty times" route, till i can get in there with some spray.

 

[acidtest64]

I did clean all of the controls a few months ago. I will be taking it apart again and cleaning all of the controls once more. As I said though, the right channel does fade back in after I've slid the balance fader back and forth several times, and they are very difficult to move despite cleaning and lubing/greasing. I do believe the balance fader is the problem. Does anyone know what model replacements work? There are a few for sale on eBay, but mostly for the 22 series receivers.

 

[Richs_Trains]

I don't think they will work, if I remember (one of mine came broken off and I did the add a tab with screws fix because I could find the direct replacement), the balance on this unit has the long shank on it, and most 22XX are the short shank. The 1122dc, 1152dc, 1180dc also have the long shank but I believe they are mounted differently (PC mount on the 3250 and wired in in the 11XX series) so not an exact replacement. I also think there is a post on AK about how to take the sliders apart and thoroughly cleaning them. I have a volume control I have been trying to get right and it seems the more I work it, the closer it gets to right, so you may just need to slide it 50 more times or so. Good luck.

 

[acidtest64]

You could try carefully taking the fader apart by bending back the tabs and see what is going on inside.
Maybe the slider brush fingers are gummed up or the nylon slide itself is binding.
Hopefully it isn't degradation of the carbon tracks themselves.

It is replaceable if not salvageable.
Pics would help

Bob

I got around to working on this one again. I unsoldered the slider balance control from the board and opened the casing, this is what it looks like. I've never seen the inside of one these, how is it looking? Any ideas?

 

[slimecity]

There doesnt appear to be a lot of gunk on those tracks or the little doofers that slide up and down them.

Perhaps one of the metal contacts at the end of the tracks is loose, or the track is cracked there?

 

[acidtest64]

Everything does look good, no cracks or loose parts. I cleaned everything up with microfiber wipes and swaps. I am going to add some faderlube and put it back together then solder it to the board in a day or two after a few others have made suggestions.

 

[Joshstereo]

I had the 3250B with the same issues and it turned out to be one of the 4 buttons for tone mode and muting. Its just hard to get at. Try taking those push buttons off the board and give those 4 buttons the same treatment you gave the slider.

 

[wlhd1610]

If you have definitively determined that it is the balance slider then I would take it apart as you have done.
Carefully clean the exposed carbon tracks with Deox Faderlube and/or a small amount of Caig D5 frollowed up by Faderlube.
Carefully clean the ends of the wiper fingers with Caig D5.
Determine if the wiper fingers can be ever so slightly bent as to put a little more downward pressure.
Lightly grease the detent ball and nylon slider.
Put it back together, with it laying on the workbench(not reinstalled in the unit).
Using an ohmeter set to the proper scale run the slider back and forth and watch for steady rise and fall of ohm readings to see if you have any sudden or complete dropouts.

Report back.
Good luck!

Bob

 

[acidtest64]

I desoldered all of the faders (balance, bass, mid, treble) from the board and opened them up for cleaning. Some of them did have gunk on them, and the wiper fingers were messy. I had actually lost the spring in the balance fader where the ball bearing rests on as it popped out when I opened the fader up. I was careful not to make this mistake with the others.

I put the fader back on the board anyhow and interestingly without the spring and ball the fader slide more easily, only it does not click into place when in the centre position. If anyone has a replacement spring or a fader lying around where I can get one, by all means let me know. Anyhow, I fired the system back up today and it is working very well again. Thank you for the suggestions everyone.