Dave Tracy

Having just removed my dash in my '64 to replace dash pads and wiring harness, I notices that my new Lectric Limited harness does not include the capacitors. Those of you who have replaced your dash harnesses, did you replace your capacitors (which ones) and, if so, where did you purchase them? Thank you in advance.

Frankie the Fink

The repro capacitors are nothing like the original paper-wrapped/wax-insulated capacitors -- if you have original use them... but they are guaranteed to be dead and harmless after 55 years.

If not, leave them off or get repros (Long Island Corvette has them) but know that they do nothing now basically. They are for AM radio noise suppression and who listens to that now?

Old, inoperative originals or new repros - they are just NCRS decorations at this point...

Sorta like Grandma's Christmas tree ornaments...

R66

If the wire comes out at the capacitor end and touches the metal frame of the dash or pedal frame, you have a fire hazard and or melted wiring (happened on R66). If having the capacitors in place for a TOP FLIGHT NCRS trailer queen is more important than having a non-scorched car, you might want to consider never putting a battery in it.
More $.02.

SWCDuke

As stated original caps probably no longer have their rated capacity in microfarads, but test that they are not shorted by measuring continuity between the terminal and case. If resistance is still infinite, go ahead and reinstall them.

Back in the sixties I took apart an old points capacitor. It internally consists of a layer of what looked like aluminum foil and mylar wrapped into a tight roll. Next time you replace the points capacitor, take it apart and check for yourself.

Duke

Powershift

Fluke multimeters and many others have a built-in capacitor test function. You can also buy a separate capacitor check meter for about $50. I have and use both. So first see if a friend has a meter you can borrow to check. It will tell you if shorted, open, and what the capacitance value is.

Larry

Dave Tracy

Thank you. I will check them tonight

Frankie the Fink

Or just snip the lead wire and epoxy it back and you'll have a nice correct-looking, electrically "dead" part to show off to friends. I'm a journeyman avionics tech and I can't recall ever seeing a capacitor shorted....

Powershift

But we have had a few shorted capacitors reported on this forum over the years that shorted out the points and resulted in ignition failure. Not many, but a few if I remember correctly.

Larry

SWCDuke

Yup, I recall those too, but aircraft capacitors are much higher quality and have to meet whatever FAA requirements are in place, so shorts may be much rarer.

Duke

tubman

Just a point of information. My neighbor is an EE and has a quality capacitor condenser tester. I tested the original capacitor on the voltage regulator and it was right on spec (the value printed on the bottom). The capacitor on the coil bracket was missing the lead, so I ordered a replacement for Long Island Corvette. It looks just like the old one (only shinier) and tested out right on the money as well.

Powershift

I recently tested a few originals from 1969 Corvette for a friend, and they were right on the money.

Larry

Frankie the Fink

Aircraft gear is indeed mil-spec, but my experience (even back to P-2 WW-II type-aircraft) was that capacitors failed mostly by loss of their insulating internal dielectric; whereas the conductors were still separated (not shorted). No doubt any component can short out I just don't remember seeing it with capacitors -- but we're talking 50 years ago..

The ones I've seen on vintage cars are usually slimy, paper wrapped examples that have long since lost their effectiveness...

Roger Walling

All flux capacitors must be changed every 5 years.

Frankie the Fink

True -- and O'Reilly has them:

https://www.oreillyauto.com/flux-capacitor?q=121g