Who has info on R&R caps in ARC D90B amp?

Does anyone have experience to share on replacing the filter caps on an Audio Research D90B?

Those grey caps stacked in the middle, any diy using ARC's "sled" replacement or any others? They are twist locks and looks like a challenge to remove, even using two soldering irons and a helping hand to pull it free.

The amp is running fine now, but discussion suggests the caps are past thier prime and age related failure is emminet.

Your thoughs please.
Aa4ec480 f745 4c1e b087 c5ba107b16fdsneauxman
I think They are 400uf at 450V. You need to use very low esr caps. Kendeil capacitor made in Italy is very good. Also Cornell Dubilier made in usa. These two companys makes the best caps for audio.
I have on many occasions R&R'd those caps. If you are unfamiliar with twist-lock-lytic removal find an ARC repair facility near you to do it for you. You don't want to damage the through hole plating on the mother board. Some of those small traces come off very easily. I only use ARC caps with the adapter. That is a major improvement over the stock twist-locks.
Thank Y'all for your input. They are 470uf/450v. I'm not sure, but I believe the replacements ARC uses are Nichicon GU Series...proabably the LGU2W471MELC. I guess these are mounted on an adapter of sorts.

Nichicon also has a KX Series for specific use in "Audio Equipment" Model LKX2W471MESC45. It has the same 10mm sanp-in lugs.

I'm not sure at this point how to mount them....anyone have some ideas or better yet...a picture, sketch, drawing of how ARC does it?

Hifigeek, I am familiar w/T-Locks, are they locked to the board and soldered or just inserted and soldered?

And, you are correct about the caution on the tracing being fragile...I received this am in failed mode and had to go through it replacing an opamp and some trace came off...using a solder sucker...bad idea - bad idea.

With your experience at recaping the D90B, what other advice could you offer?

Like I said above I would use the ARC part. I believe that amp also uses a zener diode string as part of a voltage regulator circuit. I would make sure the regulated voltage is correct once the caps have been replaced. If you are unfamiliar with repairing Tube Amps I would seriously recommend having someone do it for you. I'm sorry if I sound like a broken record. Once CB traces have been damaged, especially if the board is through hole plated, it becomes a very difficult task indeed. BTW next time you have to replace an IC, cut the leads of the IC off at the body of the chip and pull the leads out one by one. Makes it a lot easier to remove. Also, if your iron is too hot traces come off easily.
I have talked w/ARC - the Cap "Sled" is $500 !!! too much considering the amps value "used" is only $1000 - $1200 and add $490 + shipping both ways for them to do it...I already spent close to $1k retubing with NOS GE 6L6GC's & Amperex "PQ" White Lable 6922's.

With that, the amp runs DEAD QUITE and really sings, said to rival ARC's Reference Series!!! This really is one of their best ever designs.....worth keeping.

Just want to update the caps (before they fail)...I would really like to keep it as a DIY...the (8) Nichicon KX caps are only $68 from Mouser!!

The challenge aside from removing the old ones is to design a nice drop-in replacement (which ARC has). I have developed a few ideas, but it would be nice to see how they do it.

Hifigeek...thanks for the tip on the IC trick....I have the amp's voltages and balance tweeked through out..hope not to have to do the IC again.

Additionally, I 'm thinking of using the copper mesh tape to help suck up the solder during the removal process...your thoughts.

I use a solder sucker. I don't find solder wick all that useful unless I'm repairing a CB trace.
Hello Hifigeek1,

What type of solder sucker would you recommend?

I've used the quick release type and it also sucks the copper tracing off the board.

Also, the small squeeze bulb doesn't work either.

btw, the amp is still going strong, no issues or noise...just sweet music.

Thanks & Regards--
If you are sucking the trace off the board, you are overheating the trace. I just use a standard blue colored solder sucker from OK Industries.