Help identifying an electrical lead

[Healeyalt]

I'm cleaning-up the engine compartment on my 76 and on the passenger side wheel well I noticed a broken off wire and I'm not sure what it is for.

According to my service manual, it looks like it branches off from the part of the wiring harness that goes to the air-cond relay (compressor relay) and the voltage regulator. The diagram list it as going "to condenser"? But it broke off something that looks like a capacitor or something mounted on the lower part of the bracket on the wheel well.

(I hope that makes sense, its kind of hard to describe some of this stuff and I did take a pic but I can't seem to get the pic attached)

Anyhow, can someone please tell me what that little capacitor-like looking thing is this wire attached to, what it does, and where I can get a replacement?

Thank you

Gary

[clayton 260z]

A photo would help...

[Zed Head]

It is a capacitor, AKA condenser in automotive-speak. Some parts stores sell them, they're also used on the positive terminal of most alternators. I think that the capacity is the same, but if you want to be rigorous you should probably measure it. If you can't find one in a parts store, the wrecking yards are full of them, in a variety of cars.

They damp high voltage electrical impulses, also known as "noise" in the electronics world. Originally to make points last longer and for cleaner sound on the radio, but I believe that they also offer protection to the solid state electronics of the alternator, ignition and ECU on more modern cars. I've used a condenser to stop electrical noise from screwing up my tachometer reading after installing a different coil. The engine will run without it, but there might long-term effects. Nissan had a reason...

That's my current understanding (punning again).

[sblake01]

It's also discussed in this thread.

Edited March 30, 2012 by sblake01

[Healeyalt]

I guess if I had someones email thru private messaging I could forward the pic to them, but I can't seem to get it to attach to the thread probably because its too large

Thanks

Gary

[Healeyalt]

Thanks guys, I'm sure what I'm looking at is what Zed Head described. It does have some printing on the side of the casing, but its too faint to read. I do have a couple of testing meters (volts, ohms, etc). Anyone know how I would measure its "capacity" so I could find another to replace it with (I'm not even sure what I'd be looking to measure)?

Gary

[Zed Head]

Some meters have a capacitor test function. One lead on the body and one lead on the center wire. The value would be in Farads (named after Faraday, I assume). Microfarads, actually, I believe. It's mysterious...

[Healeyalt]

I was just looking at my service manual and I see there is also a condenser (capacitor) on the alternator. When I took a look at the car I see the wire is also broken off that one (its amazing this car even runs with all the vacuum leaks and other problems I'm finding.

My question is, now it looks like I need two of these capacitors and I'm wondering if they'd be the same? (I'm thinking it might be easier finding a parts number for the one for the alternator).

Thanks

Gary