SS125

iTrader: (1)

I relocated the battery to the rear of the car. There are several schematics on here that are how I sat mine up. Ran the battery side up to the starter. Ran the other side up to the alternator. Used either 0 or 1(really thick cable) for the starter and 4 ga for the alternator. From the starter, I ran a 4 ga cable up to the fuse boxes. Everything was fine. Started it up and the guage showed that there was a good charge and it appeared normal. Ran the car for less than 10 minutes. Shut it off, go to start it again and it still was cranking over slow because I know the battery was dead. But it slowly turned over until it started. Then I noticed the guage. It was now down to 13 and when you started it, the guage was slow to go up to even 13. Then it showed it below 13 so I guess it was discharging. It is the stock alternator that is currently on there. Anybody have any idea whats going on with this? I don't think anything is wrong with the battery relocation. Any help would be appreciated.

SS125

iTrader: (1)

Anybody got any ideas on this?

MikeZ06402

My knee jerk response w/o testing and looking things over is you have a weak/dying alternator. Mine is dying and I am waiting on its repalcement but it was giving me very similiar symptoms and it is in stock configuration. Before you pull your hair out, have the alternator tested and see how much amperage it is putting out. I suspect you will find the amperage output has fallen off significantly.

Not completely positive what the amperage for your car is but on the Vette it is 110A, I am bumping it to 150A so I can run a decent sound system

SS125

iTrader: (1)

Thanks for the response. Is it just coincidence that it did that exactly the first time I start it after doing the battery relocation where everybody I have read about talks about frying their alternators for some reason or another? That is what has me concerned. If it was just a dying alternator that is one thing, but to change alternators and only have this happen again due to something in the battery relocation has me concerned, although there are many on here that seem to have used this same configuration with no problems. Thanks again.

MikeZ06402

I don't believe in coincidence but I do believe in cause and effect. I think relocation of the battery (cause) put just enough amperage load to negatively effect either the rectifier bridge or brushes within the alternator. I do not think GM specs these with alot of overhead for increase of amperage draw; be it a stereo or a battery moved to the back or being under driven by 25% in my case.

SS125

iTrader: (1)

So does that mean you think I have a bad alternator?

crainholio

iTrader: (2)

Can you clarify these two sentences in terms of positive and negative poles of the battery?

libertyforall1776

iTrader: (2)

So would adding 55 watt HIDs without a relay also cause alternator issues?

Sorry, don't mean to thread hijack. But my alternator started failing AGAIN today too (2nd GM replacement already). The belt seems taught, but could an inadequate belt tensioner be part of the blame? How do you know if the tensioner is bad if the belt *seems* tight?

SS125

iTrader: (1)

This is how it is wired the switch. The only difference is I don't have the fuse in the alternator line yet.

https://ls1tech.com/forums/attachmen...1233334884.jpg

XtraCajunSS

iTrader: (2)

I know you said you ran a good heavy positive battery cable but what about the ground? The ground wire should be as large are even larger than the pos... You can never have too large a ground. If the block or battery is not grounded properly, you will see the same symptoms. Remember, the circuit has to flow equally well on each side of the battery and alternator.

Thanks,
Shane

crainholio

iTrader: (2)

The factory CS130D alternator doesn't have a great deal of surplus capacity, and modifications that demand more current and put more load on it typically push it over the edge.

I'd swap in a 145-Amp truck alternator as discussed here:
https://ls1tech.com/forums/generatio...-failures.html

SS125

iTrader: (1)

The ground off of the battery is the same as the starter wire, 1/0 I think it was. That is to a good ground I'm sure. Now you bring up a good point. The ground off of the engine block is the same ground that was up there to begin with. It is really just the negative battery cable that runs from the block to the post that was in the battery to the ground on the frame. But its the same wire, it's like 4 guage or whatever the stock negative battery cable is. As far as the battery ground, the latch in the back that the rear deck lid latches onto, I ground a spot down to the bare metal about 2" in diameter and ground it to that. Would that be adequate?

sjsingle1

iTrader: (1)

there is no need for super sized ground wires.......it either works or it does not.......make sure there is no corrosion to interfere with the ground

SS125

iTrader: (1)

The metal where the ground from the battery is is perfectly clean. Now as to the other ground up front, I haven't even looked at that. It never got disconnected.