steveo_f8

iTrader: (6)

Just curious to see who had relocated the alternator to the passenger side head area, and is having alternator issues.

My issue is that even after a short drive, say 5 miles or so, If I pop the hood the alternator is so hot you can barely touch it for a second.

Now, I am also having a drop in voltage(drops to low 11 volts at idle) after a few minutes of warm up. I think this is because its getting so hot. Im not sure if there is too much load on it, or if I need to put a smaller pulley on it, because I do have an underdrive pulley as well. When im driving it and keep the rpm's up above 2000, then the voltage gauge will start to go back to around 12-13 volts. Once I come to a stop sign/light and sit for a minute, it draws the volts back to the low 11's.

This is a brand new LS1 alternator.

Recent mods electrically are:

Battery relocation to spare tire area (2 g wires)
2 x 340lph pumps on a BAP
Versa Fueler
2 interior gauges and an electronic boost controller.

The wires going to the alternator are also very very hot, almost melting off the plastic wire cover, not sure if the load is on them or if them are hot because the alternator is so damn hot.

Any input would be helpful.

Thanks

pwrtrip75

iTrader: (8)

Did you run the ground cable all the way back up to the engine ?

steveo_f8

iTrader: (6)

No, just in the hatch area

68 SS

iTrader: (23)

With a rear mount battery I run the ground all the way back up to the block. You can't rely on grounding it to the chassis you need to ground it to the block as well.

steveo_f8

iTrader: (6)

Ok thank you

steveo_f8

iTrader: (6)

However, I did hook up another battery in te front as well for testing purposes, and even with a second battery in the factory location it did not change the voltage drop

68 SS

iTrader: (23)

Once you are positive (no pun intended) you have a good ground then I would look at the Alternator another tid bit is the alternator new or a reman? I have seen quite a few remans that were just junk form the get go as well.

steveo_f8

iTrader: (6)

It is a reman

sick_tight

i wouldnt be too worried about the dedicated negative wire too much. probably just a bad alternator.

most new cars have rear mount batteries and the neg is terminated at the chassis

also they dont have a neg post, just a positive post and tell you to put the jumper cables to chassis ground



also did you remove any pulleys with a ac delete? if its getting really hot and low voltage maybe its not getting enough RPM for a full voltage? (shot in the dark with this one) which would make it hot if the car is demanding more voltage than its producing
not saying having a dedicated negative line wouldnt help but i ran mine staight to ground as well.

steveo_f8

iTrader: (6)

Yes ac is gone. I was wondering the same thing about the alternator not spinning fast enough, because when I drive the car down the road over 2000 rpm it seems to keep the charge good. With that being said idk if its the rpms keep the charge up or going down the road at 60mph is cooler the alternator so that it can work properly.

I did not have this problem when its was h/c with alternator in factory location, and it also had an underdrive pulley then as well

sick_tight

I would look at the pully system, im thinking its the RPM of the alternator thats causing this. just to be sure rip it out and take it to an "autozone" or where ever will test your alternator. definitely not 100% on diagnosing the problem but it may help you out. also theses a mechanical fan that cools the alt so if its not spinning fast enough that could also cause your overheating issue

pwrtrip75

iTrader: (8)

Most people have this misunderstanding with the way DC electricity works. The eletricity leaves the battery on a one way path, does the work, and then returns, the entire trip is the whole process. What leaves must return, they must be equally conductive otherwise it wont work correctly. Imagine leaving your house through the doorway, going to work and then having to come back home through a crack in the door.....ya....it aint going to work. If you hinder any part of the circuit the whole trip isnt going to work.

Your heat is created by the fact that even though it left the battery it will return....but the difficult time it has makes heat because it has such a shitty path to take causes friction.

Hope my analogy makes sense. Basically to make a continual circuit work it has to be continual. All the ****, paint, body panels, car body, all add resistance. Resistance=heat which is caused by requiring higher amperage to get though the resistance back to the battery.

Make sense? Might not be your whole problem but a good contributor.

sick_tight

if hes got a good contact with a ground its the same thing. i agree a dedicated ground would be best but chassis ground would suffice. especially since OE places batteries with no dedicated ground to the battery for any of the electrical system in newer cars. they just have a grounding block to chassis ground.

the voltage didnt change with a battery in the stock location either so im not thinking its a ground issue. if he is he can clean off both grounding points and call it a day. if hes really concerned he can check continuity with the negative terminal to whereever his chassis ground is.

maybe the UD pulley slowed the rpm of the alternator and its finally taking a crap.

pwrtrip75

iTrader: (8)

No it is not the same thing. Voltage is irrelevant. You can run speaker wires to your starter and will have 12v. Put a load on it (turn on starter) and see what happens. The ammount of amperage going through that speaker wire will melt it.....but the volts all stay the same.


Having the battery in the trunk and not having a dedicated ground to the engine block, the alternator is trying to charge the battery through the chassis, motor mounts, and can even use ground wires in your harness to back feed. Its like taking jumper cables and putting the + on the battery, then throwing the - one out and using a speaker wire.

Ever use a set of jumper cables? If you use a small thin cheap set they heat up, take forever to work. Use a thick heavy gauge wire set and the car jump starts much faster.

sick_tight

thats why im saying if its a solid gound like to the frame, its good enough. if you cant use chassis ground then why do cars have rear mount batteries and no dedicated grounds to the alternator?

i completely agree that a dedicated ground is best, im just saying its not necessary. if the OP drove around with the 2nd battery and the alt didnt get hot then i would consider the ground. imo.

pwrtrip75

iTrader: (8)

What cars are you talking about? Every car will be different. Ive known quite a few people that have done the battery relocation to the back and experienced problems. The amount of resistance in a car body or frame is quite a bit, maybe a car that isnt drawing much power wont be affected as much as a car with multple things ran off the.......battery or the alternator? Then you reply on the alternator to charge the battery....how so when you cut half its circuit? Best thing to do to diagnose the problem is fix the known issues. The ground in your pic is worthless and im surprised the car even functions. Run a ground cable before you burn the thing down.

sick_tight

its a picture of a OEM battery location/wiring for GM.

when i did my relocation i had zero issues with grounding my battery to the crash bar bolt underneath the car and the alternator to a ground on the front of the car, i was running 2 amps and a 160 amp truck alternator. but like you said i agree that the ground wire would be best but its not necessary for a car to perform properly

steveo_f8

iTrader: (6)

I did not drive the car with the second battery in the stock location, just tested for voltage. It still wasn't putting out enough volts at idle, (low 11 volts)

The ground wire could be the issue with the overheating alternator, and once the alternator is that hot, then it can't run to its potential and put the right voltage out?