Voltage will build inside the capacitor and look for a way out normaly in the form of smoke
If smoke is coming out then it may have been fitted with British electrics...
Subject: British Theory of Electricity ... Electrical Theory by Joseph Lucas.
Positive ground depends upon proper circuit functioning, the transmission of negative ions by retention of the visible spectral manifestation known as *smoke*. Smoke is the thing that makes electrical circuits work; we know this to be true because every time one lets the smoke out of the electrical system, it stops working. This can be verified repeatedly through empirical testing.
*When, for example, the smoke escapes from an electrical component
(i.e., say, a Lucas voltage regulator), it will be observed that the
component stops working. The function of the wire harness is to carry
the smoke from one device to another; when the wire harness *springs a
leak*, and lets all the smoke out of the system, nothing works
afterwards.
Starter motors were frowned upon in British Automobiles for
some time, largely because they consume large quantities of smoke,
requiring very large wires. It has been noted that Lucas components are
possibly more prone to electrical leakage than Bosch or generic Japanese
electrics.
*Experts point out that this is because Lucas is British and all things
British leak. British engines leak oil, shock absorbers and hydraulic
forks and disk brakes leak fluid, British tyres leak air and the British
defense establishment leaks secrets .. so, naturally, British electrics
leak smoke.
*From the basic concept of electrical transmission of energy in the form
of smoke, a better understanding of the mysteries of electrical
components, especially those of Lucas manufacture, is gained by the
casual user.