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Marantz 2500e.. needs a bit of elbow grease

Heh, yeah, the dishwasher is not my really recommended cleaning option, probably would destroy the bottom rack anyway!

When you have a chance, let's see some before and after pics. As Sam noted, if the unit was run in that setting, the cooling tunnel would likely be very thick with dust and debris. It will be interesting to see how that looks.
 
Good old rubbing alcohol on the white stuff which is just the last of the flux. If I'm going to de flux a board I use a machinist scribe to pick off the majority first. It usually takes 3-4 rounds of alcohol to get it all.
 
Windex is your friend. I stand the board up and give is a good scrub with isopropyl alcohol and a toothbrush. Once the flux/alcohol mix is running down the board, I give it a good blast of Windex and blot dry with a micro-fiber cloth. I guess the alcohol is lighter than the Windex so it floats on top of it. That way it doesn't get stuck back on the board when it dries. It trully amazed me how well it worked the first time I tried it.
 
I cleaned a 2270 that was as bad as that. Compressed air, a paint brush, isopropyl alcohol, and some deoxit. I'm expecting to see pictures of a clean receiver any day now.
 
Jerryfan said:
I cleaned a 2270 that was as bad as that. Compressed air, a paint brush, isopropyl alcohol, and some deoxit. I'm expecting to see pictures of a clean receiver any day now.
Click to expand...

Did you do it with all of the boards in place?
 
I did. For compressed air I used oxygen tanks (I deliver medical supplies). Q tips and pipe cleaners are your friend
 
Stem cleaning?
Humm usually water & heat are things that electronic components dont mix well:thumbsdn:

Since the receiver works I would go with the soft brush & vacuum method.
No need to get over zealous with cleaning fluids & mess up a working circuit board.

I have found it is better to suck up the loose dirt & remove it.
Rather than blow it around with high air pressure especially around the tuning fins. Yep I prefer sucking to blowing LOL!:smoke:

I have had very good results with the non abrasive MR Clean Magic Erasures & dishwashing soap & a soft tooth brush on the knobs & face plate.

Can’t wait to see her all cleaned up!:thmbsp:

Cograts that is going to be very nice receiver when done.
PQ
 
I had found some information on steam cleaning circuit boards and electronic assemblies.. Looks like it's common practice however you need the right unit. I have a small high pressure steamer that might work. The problem is that nothing is loose, a vacuum or even an air compressor won't budge the stuff.

In any case I think the plan will be to partially dissemble the unit:

Face plate
Amp tunnel
Power supply
Scope

Once I have each piece apart I'll use the windex and a soft brush to clean everything up followed by an IPA rinse and compressed air as others have recommended.

Hopefully pulling the modules out won't be too bad.

I can't touch the unit for a few days, had to leave the country for business :(
 
Progress...

So I was able to clean the unit up. I ended up using a bit of window cleaner, heavy duty simple green, water and about a gallon of isopropyl alcohol. That and about an hour of compressed air.

The process was not without problems...
The sticker on the top of the tranny is messed up.
The chassis needs to be detailed. I have been using a bit of deoxit on a rag and everything is cleaning up nicely.
The top of the frame and tranny cover are pitted, I am thinking about how to fix it, I may just use some rust neutralizer on the frame. I am not sure if the tranny cover comes off or not. If it does that would be really great, I could repaint it and duplicate a sticker.

The face plate cleaned up OK.. I used some warm water and a magic eraser. There are some cloudy spots that need to be addressed. Also some of the lettering was gone before I started, it's limited to the balance control slider. I was thinking of using letterset or something similar to restore it. Any suggestions?

I was able to get the tone control board and attached switch board out for component ID and recapping. I am making an excel spreadsheet of the actual printed values on the caps, I have found a couple errors already in the schematic.

I have been following Rbuckner's awesome rebuild thread for a 2500. It's helped me a bunch. Thank you!

Pictures to follow later..
 
My pleasure to have helped! I'll be tracking with you as you help this monster out of it's slumber. Bummer about the wrecked lettering, I don't know a good method of fixing it. The fogging might be the anodizing having worn through like the lettering. I'd try wiping on some Armorall and see if it blends it in. That would end any chance of repairing the lettering as nothing would stick after that though.
 
For lettering, maybe would recommend finding some good fonts that duplicate the original and then printing on clear adhesive sheet with a laser printer. Then cut and adhere. The problem with Letraset or other similar is they are very hard to find now, and still require you to expertly transfer to the surface, plus you still have to find some way to protect them from wear just by use of the control.

Maybe we could commission TMZ2 to make some replacement 2500 or 2600 faceplates, I know he's already tried some 22xxB models which are similar. I've never seen a 2500 in black before but if it looks anything like the 22xx and 44xx he's already done, it could looks stunning. Won't be inexpensive though.
 
rBuckner said:
My pleasure to have helped! I'll be tracking with you as you help this monster out of it's slumber. Bummer about the wrecked lettering, I don't know a good method of fixing it. The fogging might be the anodizing having worn through like the lettering. I'd try wiping on some Armorall and see if it blends it in. That would end any chance of repairing the lettering as nothing would stick after that though.
Click to expand...

I am going to tackle the lettering last. The good news about it is that it's limited to one word.

I do have a question about caps. I see that you have replaced many of the film caps along with the electrolytic's. Did you do this for every board?

I don't have a problem working on anything in the amp section but I am a bit concerned about the tuner. If I start replacing caps and it goes out of alignment then I may have a problem. I have a sencore SG165 that I can probably figure out how to check the alignment with but if it's off I am not sure that I can correct it. Maybe I should just skip the tuner?
 
As my friends said, do the electrolytics but not the film or ceramic caps in the tuner sections. My reasoning is that FM is frequency limited to begin with and has a minimum distortion level that makes any upgrades to film caps a minimum return for the cost and effort. Then there's the multipath distortion, maybe not up to par transmitter and antenna towers, etc. That may not be everyone's reasoning and take on things.
 
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