What is the best way to test the complete setup while dash is still out of car. I've tested the radio and 8 track player with just a speaker and all is good but before I place dash in car, I'd like to test everything related to the system in case the Rear Speaker switch is bad or noisy as well as the crossover box. All 5 speakers have been re-coned and I'm not sure I can wait any longer to see what it sounds like plus if there's something that needs to be worked out, I'd much rather do it out of car. All speaker wires have been cleaned up and tested. The dash wiring harness is new.

I was thinking that I could just provide 12V to radio, ground and connect speakers but I'm not sure if the other devices within this schematic would get the necessary voltage.

Any ideas would be greatly appreciated.

Clip lead the speakers and crossover boxes into the radio. The crossovers are passive devices and take no power to operate. As a matter of fact, all of it is passive except the radio itself. Put a small screwdriver into the antenna connector (Motorola jack) with your finger on the screwdriver blade. Should bring in higher powered local AM stations. Also should be able to receive FM stations as well.
It will not sound as good as it will in the car as you do not have enclosures around the speakers. But the speakers should all work.
Craig

So I can just connect radio speaker plug to dash speaker harness, connect crossover and fader, rear speaker harness, ground and provide 12v to radio with my antenna connected?

I hooked it all up per your guidance and everything is good except for the left front. Hopefully it's just a wire issue somewhere in the harness because speaker works when connected directly to radio. I will ohm it out later.

Thanks for the help on this

You can check a speaker with a flashlight battery and clip leads. It should pop with contact to battery. An ohm meter can check if the voice coil is open. But if it works hooked up to the radio, it is a harness issue

Ok the left front speaker works fine when directly connected to the radio but doesn't when connected to harness. I've ohm'd the left speaker colored wire all the way to the crossover connector as well as the ground and it tested good. Just to be sure a working speaker ohms out the same way, I performed the same on the right front speaker with matching results. The left rear speaker works, rear speaker control switch works because I can fade all the way to front and balance all to left. When I do this, the center speaker puts out sound but not the left. It does this with 8 track tapes as well as AM radio.

Could it be in the crossover box or the radio itself?

Thanks for the help.

Ok I thought of another thing I could do to test if it was the radio. I moved all the sound to left front again via fader and balance then directly connected speaker to radio and it works so it's not the radio.

Am I missing something? Could it be the crossover box?

Could be the crossover box. Not much to them, just resistors, coils and capacitors that split the audio into higher frequencies for the two outside front speakers. The rear and center speakers get the full spectrum of audio. The capacitors I believe are non polarized electrolytics that are hard to find. Resistors and coils are easy to check with an ohmeter and seldom fail without obvious burn marks.
Capacitors will show lower ohms when touched with meter probes and then go higher as it charges up. Reverse the leads and it will do the same again.

Are the capacitors black in image? I have to admit I really don't know the difference between a resistor and capacitor.

If it is the black item, there are three in this box. I hooked everything back up and I get a reading for two of them by touching meter leads to each lead coming out of capacitor. The bottom one in pic is the one that isn't showing any signs of life. All of these have the same printing on them and there aren't any burn marks on assembly. There is however a crack in the capacitor.

Thanks for hanging in there with me.

Yes they are, and a crack is not a good thing. The electrolyte is all gone.
That is an electrolytic capacitor. You will need one of the same or similar value with a voltage of around 25 volts or more.
Craig

40uf is an odd value. Next standard value is 47 uf

http://www.mcmelectronics.com/product/31-8540

or tie two of these in parallel:

http://www.mcmelectronics.com/product/138-222213838229

or see if you can find another crossover box.
Craig

I have to admit this is all above my knowledge but I'm learning so thanks for hanging in there with me.

I went back and re-tested using volt meter set to volts this time and I'm getting a reading from all three. All three capacitors are reading close to the same voltage. I'm touching each lead coming out of capacitor with the meter leads.

I've went over the harness a number of times and there aren't any issues that I can see. Ohm'd the ground all the way from the left speaker connector to the ground on the crossover as well as the Green/blk (left)wire.

I'm asking around to see if I can borrow a crossover to see if that's the issue but those are kind of hard to find as you probably know.

Thanks for your help on this.

Any other suggestions?

You can bypass the crossovers with alligator clip leads. Only do it briefly and without much volume. The small speakers are not rated for the power to pass bass response. Full volume would probably get rid of your new voice coils. If there is sound out of the speakers, it proves that part of the crossover is bad. A multimeter probably is not a good indicator for voltage. An audio AC voltmeter would.
DIY speaker dealers such as MCM carry crossovers for building home speaker systems. a two way crossover that sends bass to the center speaker and treble to the outside speakers would work. The crossover would be marked woofer (bass) and tweeter (treble).
Craig

what happens if the crossover is eliminated and just a pair of front and a pair of rear speakers are used ? my charger did not come equipped with the am/8 track, but i swapped one in way back in '71 and did not know about needing the crossover. using it that way for many years, have i done damage to the unit ? last time it was used was 1980 or so, and then the car was in storage until 2000. only had the car out a handful of times then, and has been in storage since. when i get it back out, what should i do to freshen up the unit other than acquire new speakers and ??? about the crossover. or should i be able to go to the local ricer stereo shop for some kind of amp setup ? not looking strictly for originality, but i don't want to further damage the unit any more than i possibly have already. i hope this has some relevance to the original post.

Incorrect parts...
The capacitors used in a speaker cross-over are non-polarized...
Here is a link for a source..

http://www.parts-express.com/cat/non-polarized-electrolytic-capacitors/1385

Just my $0.02...

A friend had a crossover I could borrow. Plugged it in and still same issue. I'm really not sure what else to check.

Don't know why I didn't think of it but I should have borrowed the wiring harness as well.

At this point I'm not sure if it's the crossover but in case it is, would a 100v be ok to use? I found two 47uf on this site but they are rated at 100v.

After trying the borrowed crossover didn't change anything, I jumped over the capacitor like you suggested, turned radio on and I have sound from the speaker. So I guess the same capacitor is bad in the borrowed crossover. That's my luck. Lol.

Now we're getting somewhere. I'd like to keep original crossover box and replace the capacitors. Question is which will work? I'm confident in my soldering abilities but not so much in determining exactly what is needed.

Thanks for the help

I am confused on the non polarized capacitor. While most crossover capacitors are non polarized, the one in the picture is clearly marked with a positive terminal. Non polarized capacitors are not marked that way because they are by definition non polarized.
Maybe it was replaced at some time and should have been non polarized.
To answer your other question, yes 100V is just fine. That is the working voltage and it just has to be higher or equal to the replacement.

I took cover off of borrowed crossover and capacitors are identical.