small meters have small internal batteries and can not fully test the  insulation value a condenser.  a higher voltage is needed to  check for  internal leakage which will short out the  coil kickback voltage

at bare minimum   you can build a small  test circuit like this one.  it does not  have a voltage doubler to reach  250 v+  but should be better  than a  3-9volt  battery

see link on cap tester  illustrated in above drawing

home made coil and condensor testers | Antique Outboard Motor Club,Inc (aomci.org)

In response to someone “testing a box of old condensers”, I acquired part of a member’s collection to sell for his widow.  In the mix was a box of NOS and used condensers.  There must have been upwards of a couple hundred.  I tested all of them using a Heathkit C-2 condenser tester.  When tested at 300V, three of them were good.  One was a brand new part, the other two were original condensers from a Johnson A.

If you are serious about testing condensers, I suggest finding a Heathkit C-2 or C-3 condenser tester and recapping it.  They can tell capacitance as well as leakage at high voltage, and can also be used as an ohm meter.  They are a bit expensive; about $75 to $100 on Ebay, but you might find one locally at a flea market.  Recapping will run about $20 or so for parts.  But the cool factor with the magic eye tube is worth it if you’re going to get some use out of it.

This is what the C-3 looks like; the C-2 is the old style tan with red lettering.  The C-2 is usually a little cheaper than the C-3.  Circuit is pretty simple.

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