Restoring Vintage Multi-Section Electrolytic Capacitors

As electrolytic capacitors age, their electrolyte dries up causing their electrical capacity to drop and leakage current to increase. It is definitely a good idea to replace 50 year old electrolytic capacitors.

Multi-Section Capacitors, which were aluminum cans containing several discrete capacitors all connected to a common ground, were popular in the 1950s and 1960s. There were used mostly in the power supply sections of vintage electronic devices. You can purchase replacement multi-section capacitors but they are expensive. I typically rebuild them by replacing their guts with inexpensive discrete capacitors of the same or slightly greater capacitance and working voltage.

View of the multi-section capacitor, circled in red below, in the AJ-10 Tuner from the top of the chassis.

Pictured below is a multi-section capacitor removed from the chassis. The side of the aluminum can indicates capacitance and working voltage of the internal capacitors. 

The guts of a multi-section capacitor, pictured below. I use needle nose pliers to un-crimp the bottom of the aluminum can exposing the innards. I always wear nitrile gloves when working with the guts of capacitors as the remaining electrolyte may cause skin irritation.

I use small brass screws, obtained from a craft store, to hold the terminals of the multi-section capacitor in place. I then solder the new replacement capacitors to the terminals on the capacitor base. The grounds of the capacitors should connect to the outer ground ring. I use a dab of hot glue to secure the capacitors in place. See the results below:

I use a Dremel with cutoff tool to remove the area from the base of the multi-section capacitor's aluminum can that I bent with needle-nose pliers for dis-assembly.

Below is how the multi-section capacitor's aluminum can looks like after cutting and smoothing with fine grit sandpaper.

Once the refurbished multi-section capacitors is mounted and soldered back into the circuit, I use hot glue to affix the aluminum can over it.

The refurbished multi-section capacitor looks as good as the original! See below: