How to clean a tuner (analog)

Of all places, Rat Shack now sells a non-residue electronics cleaner. Worked on the two tuners I've brought to life so far...
 
I cleaned the tuner last night, spraying cleaner only where the tuning shaft passes through the frames that seperate the gangs. Noise gone! The only bad thing that happened was the tuning knob now slips a bit from the dial pointer occasionally. This never happened before.

I guess some of the cleaner made it's way into the area where the tuning chord contacts the knob. It must need to be re-tensioned. Strange to me because this is a McIntosh MR77 and the tuner capacitor where I was cleaning is nowhere near the tuning knob.

But thanks everybody for the help (I've never cleaned a tuner before) and with the nearest shop a 2 hour drive away, this saved me a lot of driving! 8 Hours!!

Gary
 
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Gary,
Try cleaning the dial cord and the tuning shaft where it wraps around, with isopropyl alcohol.
 
the only thing I could get to stop an old boat anchor dial from slipping was rubbing a piece of beeswax on the cord. Totally eliminated the problem. I had cleaned it prior, but I don't know if that matters.
 
I'm a little slow....

Anyone want to point out exactly where in this picture I should apply the cleaner????

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Thanks.....:thmbsp:
 

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The tuning cap on the left is for AM, the one on the right is FM. On the FM cap, you can't see where the contacts are from this angle, but I drew arrows to where they might be. On the AM cap you can see better, and I drew arrows to the locations of the contacts. Examine the AM cap and locate the contacts. Then look into the FM cap and try to locate the contacts inside.
 

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no luck...

Went back to my Marantz 2325, and carefully dripped Faderlube on the contact points, and worked it back and forth. Still no luck. Here are the symptoms....

Occasionally when turning the unit on, it plays stereo for a short time, and then fades to mono.

the signal strength meter will move back and forth, seemingly not able to hold onto the signal of a VERY strong station.

The tuning meter seems to deflect mostly to the right. I tried taking the cover off the MPX and the Antenna section of the tuner and tapping around with the erasure end of pencil. Nothing. I also tried using compressed air spray as a freeze spray, and in the MPX section, that seemed to make the tuning meter deflect more to the left when moving the dial, but that was temporary.

Pushing in the mute button stops all sound from even the strongest station locally.

Anyone have any ideas? this unit does have a lot of marked accessible pots and controls for both the FM antenna section, and the MPX section. If carefully marked, would I still be asking for trouble to mess with them????

Otherwise, I suppose I need to find a SS tech to do the repair/alignment for me....:sigh:....:tears:
 
An alignment will probably be needed, but I still think the tuner is not cleaned, because Faderlube is NOT a cleaner. You need to clean it well with some non - residue cleaner, like this:
http://www.mcminone.com/product.asp?product_id=20-2005&catalog_name=MCMProducts
Then follow up with the Faderlube.
You can also try tightening all the screws that hold the IF board to the chassis. You can lastly check the power supply voltages to the tuner, MPX and IF sections.
If none of that pans out, it's got to go to a tech. You need at minimum, a stereo FM generator, distortion analyzer and oscilloscope to do an alignment. Twiddling the adjustments will just make it worse.:nono:
 
I have some old Rat Shack TV tuner cleaner. Will that work? If not, Ill get some....

Also, what would I be looking for as far as the voltages go?

Thanks...
 
It has to be non-residue. If the RS stuff has lubricant in it, don't use it. The voltages will be in the schematic in the service manual.
 
I've got a sansui g-7000 with tuner problems. When I opened it up, I found that some kind of insects (look like gnats) had taken up residence on the tuning capacitor, died, and stuck there. What's the best thing to use to clean off the bug guts? Compressed air helped, but these little guys are attached pretty well. And what is CAIG MCL?
 
Try using a non - residue contact cleaner, hose the fins down really well with it, see if it softens the bugs. Caig MCL has been re-named FaderLube.
 
I've been cleaning the tuner blades with 90% isopropyl alcohol with a soft toothbrush. I find that it works pretty well.
 
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