Alt wiring [Not big 3 wire's, The 2 wire plug.]

[z0n3d0u7 10+ year member]

A buddy of mine got a new engine put in his car, And lets just say he got what he paid for.

We went to put his sub's / amp that was in the car before the swap, Back in. Nothing changed, Power wire was still ran the same, Same RCA's, Same deck, Ev-er-y-thing. [/katt williams] and his amp will play fine to like vol 3-4, then after that it throws it into protection mode.

So i checked polarity of all the subs, Ground, Power, ect. Then i got to looking at his Alternator wiring, And noticed that the Red wire from the two wire plug went around to the Positive terminal on the alternator. Is this how its supposed to be?

on my 305 [same engine basically, His is a 350. But everything outside should be the same, Especially since the car's are both 80's G-body's.], The positive wire goes up into the wiring harness, And back into the dash, I believe. [Too lazy to trace it.]

My DMM's trash, So i dont really have means of checking the power at the amp, alt, batt, Any of that.

Anyone got any insight?

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[DonH 5,000+ posts]

what amp? what subs? my belief is that since the amp is going into protect and still has power is the subs are wired to a load the amp cant handle!

 

[scoob8000 10+ year member]

They took a shortcut, must not of been the right wiring harness or something..

That wire is really supposed to go to the charge light circuit, but more importaintly it's what activates the alternator.

It goes to the voltage regulator and tells it how much voltage to put out.

They do this a lot when putting newer "1 wire" alternators in older cars. BUT, that wire should be going to the + battery

terminal. You want the alternator to see battery voltage, not it's output.

I doubt that's the problem though, double check all the engine grounds.

(On a side note, I bet his "charge" light doesn't come on when he turns the key anymore...)

[edit]

See if this helps: (The colors might be different, but terminal positions should be the same)

http://post.mach-five.com/posted/1/Car_Stuff/charge_ckt.jpg

 

[z0n3d0u7 10+ year member]

Thanks alot.

And ur right about that not being the problem [Altho i knew it WAS one when i seen it.]. His amp got wet [so he later confessed.], And is stuck in protection mode. I hooked it up in my sisters car, With 0 load on it, And it was still in protection.

I had 3 12" audiobahn's wired to it at 2.66 ohm's, Before the engine swap. We pulled the whole system, So the shop wouldnt try to do it for us and he left the amp in a trunk that leaked.

His alt light DOES come on, but at random times. This whole swap's been a complete disaster. I shoulda done it, And took his $1500. Here's a few things ive found THUS FAR.

-Exhaust leak @ head.

-Car was completly out of fuel when we picked it up from the exhaust shop, Meaning he NEVER HAD IT IDLING, nor drove it.

-Timing's definantly wrong.

-Alt post was VERY loose.

-No hose clamp on the top rad hose, Which needs to be cutdown / Replaced as it hits the hood when closed.

-A rubber hose on the ****** lines was cracked from point A.

-no speedo

-charge light [Thanks, More to fix.]

Live, Learn, I guess.

Edit: I had a cap, that i ALWAYS bash on. And one of his "Mechanic" buddy's, Who claimed High volt alt's put out up to 200 VOLTS //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif told him he was SURE a capacitor would fix the problem. So not caring one bit, Knowing it wouldnt help nor hurt, I put it inline with his amp for him. It was peaking around 14.8v, on the cap. My multimeters fubar'd, so thats the only reading i could get.

 

[scoob8000 10+ year member]

Sounds like a mess. Been there done that with bad shops before. Had the ****** rebuilt in one of our cars, took it back 7 or 8 times, total they had the car over 2 months time, and nearly a year later still isn't right..

As for the amp, maybe take it apart and hose the board down with some contact cleaner. Maybe the condensation/dust mixture is causing a partial short inside..

 

[z0n3d0u7 10+ year member]

I will try that. Thanks once again.

What gets me tho, Is at first it would play, Just not over vol 4-5. THEN, i hook it up with NO load, and it STAYS in protection mode?

He's wanting to upgrade anyways, But, Getting it to work would help a bit.

Taking it apart's already proved to be difficult.