I am putting a reasonably big stereo system in my 78 ford f150 custom and i had to get a Ho alt and i got a 170 amp from bronco graveyard and i started the truck with it installed and it ran for two minutes and the engine shut off. Its a one wire and i ran 0 gauge wire from the alt to the battery. The alternator is self regulated but idk. How do i set the alt up so it will keep the truck running and burning down the truck?

 

Yes that's too much "power". Focus more on your exhaust tone.....less on the tunes.....no one is impressed by an obnoxiously loud sound system, other than you.....trust me. On the other hand a good exhaust note turns everyone's head.

 

well, on the other hand, I find an obnoxiously loud exhaust just as, if not more annoying - you can always turn down the volume but you're stuck with your exhaust - as are your neighbors. To the original question - how much does the amp draw and are you sure it is the problem? If you disconnect the fuse in that giant 0 power wire, does it make a difference? You may be blaming a different failure on the amp.. could be the alternator itself is faulty, or it could be showing up seriously bad grounds elsewhere, lots of possibilities.

 

the amp is a 2000 watt not sure of anything except when i unplugged the alt the truck started (but moments ago i just retried to start the truck without the alt hooked up and it didn't start) i don't have a fuse between the 0g and the battery i have redone most of the grounds but am going to redo more tonight. The alt is brand new so i doubt its the alt. But yeah there are a lot of possibilities.

 

Yes, this is exactly how you go about burning the truck down. I was young and stupid once and did the same kind of thing, only mine was a 12 gauge wire directly from the battery to the amp. When it shorted out, it set the wire insulation on fire inside the engine compartment. Fortunately I managed to keep it from turning the entire car into a BBQ. Put a fuse in! Not now, but yesterday. Seriously. If you have to ask the question, you know the answer. I think I only spent like $30 to put in a mega fuse when I installed my 3G alternator.

What is the rated power draw of the amp? 2000W is not nearly as important as how much amperage it is actually pulling. Hook up an amp meter probe to verify that the manufacturer specs are accurate. A lot of manufacturers like to exaggerate to make their amp seem bigger than it is. Also, when the truck died, what is the voltage of the battery? If the battery is not new and you are putting a lot more stress on it with a high draw amp and a much more robust alternator, it may have developed a short in a cell. I would start with having the battery tested, but also eliminate a bad alternator out of the box and have it tested too. A lot of the "box" parts stores will do both tests for free.

 

Did it run before you swapped the alt? Do any other work?

I just looked at the alt on Bronco graveyard here:
https://shop.broncograveyard.com/Hig...tinfo/28602DS/

Your positive battery cable sounds fine. Do you have a battery negative to engine, battery negative to body, engine to frame, and frame to body grounds? I'd be looking at the output voltage at idle. They say it shouldn't be an issue with the 170A, but you might get belt slippage and need the next shorter belt. Is the trucks idle rpm correct? How's old is your battery?

 

neg to engine CHECK, neg to body I DON'T THINK SO engine to frame NO frame to body NO the truck doesn't start with the alt hooked up so i cant check the voltage at idle and it does not have a tachometer. the battery is brand new 3 months ago

 

the rated draw of the amp is 1400 rms the voltage was 12.3 the battery is brand new

 

RMS is more a power output for the speakers than it is an AMP draw for your amplifier.

How big of a fuse does the owners manual for the amplifier say it needs? Typically you want an alternator that can support 125% that amount as well as the other electrical functions of your truck.

 

Wattage is amp multiplied by voltage, reverse that and you can get the amperage draw.

2000 Watt / 12v = 166amps.

Most amperage companies round up on the wattage number to make it look stronger. So it's probably not actually 2000.

That is also the amp draw at MAX power. Not a constant draw.

I have a feeling you turned up your gains all the way. Little hint, not only does that use more amps, its overheats your amplifier, burdens your speakers, and overall makes it sound crappier.
When setting your gains it is best to turn the gain to -10, turn your stereo all the way up, the adjust for more gain until the speakers start to distort, then back off a small amount. My gain is set to -2. As in I turned it down, not up. Makes it sound a LOT better, and uses less power too.
(ignore if you already know how to set gains)

 

i have a 200 amp fuse

 

thank you for all the support but none of these replies are helping

 

How many mf is your capacitor? Sometimes the cap charging all at once will kill the alt and/or suck the battery dry or combo or both on our trucks. Will also blow inline fuses. I have 3000 watts running at 2 ohms in mine for the subs and had to put a slow blow fuse with aSwitch wired to my cap and then inline fuse to alt to allow it to charge slowly. It takes about 5 minutes for it to charge. Stereo still works but the 2 12"s just won't hit hard and cause the fuse to slow blow or in essence just cause
​the 2 amps to cut off. I also upfraded the alternator and all is well. Working a high end stereo in old 40 year electronics can be tricky. Heed the warning about burning your truck to the ground. Over think every electrical connection and ground, ground, ground!! Lol
good luck
Referance:
2 12" rf subs
6 focal assorted speaker sizes
2 1500.1 rf amps
2 mbquartz 800.4
2 rcf rf 1 farad cap
1 mbquartz 500mf cap

 

I also have my gsan turned down.
Trying to push through an old metal truck. I learned real quick, there isn't enough dynamat in Earth to keep it from shaking and vibrating to death. In retrospect, I put way to much amperage into the truck. I had always been a big sedan car stereo guy. You will be surprised how little power you need to make it sound amazing with big low end bass hits.
Also, dynamat the every square inch of the interior, if you don't. You'll regret it. It sounds muddy and washed out..

 

The truck doesn't start if the alternator is connected and the amplifier is disconnected?