DaveC wrote in
:

Relay-logic controlled printing machine, 110 vac.

A 300mfd (150v) electrolytic cap is used together with 25K (25 W) ohm
wirewound pot and a 5K ohm relay coil to control a variable time delay
before the relay opens.

The cap is shot (measures less than 1mfd).

What was the existing cap? Any clear indications as to why or how it failed?