[joepaisley]

For equipment that's been in storage for 15-20 years, is it a best practice to reform the big supply caps only, all caps over a certain voltage level, or just assume the 'lytics are vulnerable and should be replaced regardless.

Thanks!

[k_roosa]

Was the storage climate-controlled? If not, wouldn't hurt to test them with a multimeter, and possibly reform them if they deviate slightly out of normal spec and don't have visible signs of electrolyte leakage.

[FullRangeMan]

For equipment that's been in storage for 15-20 years, is it a best practice to reform the big supply caps only, all caps over a certain voltage level, or just assume the 'lytics are vulnerable and should be replaced regardless.

Thanks!

What equip is this ?
What are the caps brand/size?

Just dont connect this equip to the wall and power on, this may damage the caps, you will need a Variac to slowly energize these caps to dont shock the storage fluid since they are years with no tension.

In 2007 I came to life a Sony CD player from a friend who was stored under the bed since the 1990s and its working fine til today, but I run It for several days starting from 20V in steps of 10V for 6 hours each up to 120V, these Japanese CD Players dont disappoint.

[Drrick007]

I’ve had good results by using a Variac and slowly increasing the line voltage over a period of a day or two. Just watch the current draw for any sudden spikes as you increase the voltage. A spike may be a cap beginning to overheat, in which case a replacement is called for.
I’ve done this many times on gear that’s been sitting for 40-50 years, with probably a 90%+ success rate.

Peace,
Rick