Marantz 2240B crackling/popping

[sanjib]

First, do the left amp and check that it cured the problem. If the left channel comes out fine then do the same replacements for the right amp board.

 

[nhecht]

Will do, thanks again Sanjib. I really appreciate it!

 

[sanjib]

I hope your problem will be solved. Please let me know after you perform the works.
Thanks

 

[nhecht]

So I'm trying to start detaching the left amp board from the chassis and I'm realizing it's most likely going to take some desoldering of some connections. Pics below. Is there a smarter or easier way to go about doing this?

 

[sanjib]

I never worked on this model. If you don't have enough slack on the wires after taking the wires outside of white plastics clips then you need to desolder those wires from the pin.

 

[nhecht]

Yeah it looks like that's the only way. Thanks!

 

[David Whalen]

Take pictures from a variety of angles so you can reference wire connections for reassembly. Mark wires with strips of tape. Use a numbering and color coded system. Mark places on the boards with various colors of permanent marker.

 

[nhecht]

Great tip, thank you David!

 

[AE Bob]

I think if you remove the output transistors, the clip holding the LV-2 temp sense diode, and remove the 4 screws holding the board to the standoffs, the heatsink will come free from the transistor sockets, and you can get to the back of the board to do the soldering. If necessary I believe with the heatsink removed, the PC board (and transistor sockets etc) can be brought through the chassis, and out the bottom (with the wires still connected).

 

[nhecht]

Voila! That worked like a charm, thank you for saving me from extra work, Bob!

 

[nhecht]

It's taken me a little while to get back to working on this, but we're in business! I replaced the electrolytic capacitors and the two transistors Sanjib pointed out -- H702 and H703. Everything is working beautifully now. Thanks again for weighing in, everyone! You're all very generous with your knowledge.