battery relocation

[DavidT]

If I decide to put the OEM battery in, will I NEED TO GET A $100 Moroso battery box, or will my hacked up Walmart box do? In other words, how dangerous are the fumes?



I ditched the cable that originally ran from the neg. terminal at the battery to a ground at the fender area. Now I am ONLY running the SINGLE black wire to a ground. This OK? I noticed Skye kept BOTH black wires (see his pic)...

 

[Vroom]

Well, you SHOULD get a sealed battery box, but I'm still running my Walmart box with OEM battery and I'm still here... supposedly the vents in the trunk, with the AC running, are enough to expel any fumes. The amount of water that gets used in the battery is equal to the fuming it's doing, supposedly.

You can use a larger negative cable to the ground on the fender, but I'd keep the other ground cable in tact. I didn't bother to trace where it goes but I think it ground at the block, which is a good thing. I could be wrong, though.

 

[DavidT]

if yours is like mine... the black wire that is running from your ground (bolt from the battery tray) and is heading to the hole in the fender, is actually a ground on the fender area. Its not necessary is it?


Also, I noticed today that while I am cranking my car to turn it on, my volts gauge reads 11.7 volts just prior to the alternator kicking in. Is this due to the extra 20 ft of battery cable?


My Odyssey is STILL reading low 13volts under full load (AC on) and after car has been fully warmed up. I was hoping the relocation would help...

I am wondering if my 6 month old Odyssey is kicking the bucket. It seems it will only maintain 12.3 volts after the surface charge, instead of the full capacity of 12.8 volts. Although I have no starting problems...

 

[SHOZ123]

I just went and checked my battery volts. The car has been sitting for ~40 hours. I have the PC 925 and the voltage read 12.33 volts, the battery is 2.5 years old.

One way to ensure a longer battery life is to lower the strength of the acid (electrolyte) that the battery contains when fully charged. The lower specific gravity of the acid the longer the life but you do give up some performance but will lower the open circuit battery voltage.

There are other tweaks they can do probably in the plate grid alloys and then the positive plate paste formula and curing to improve performance

Seeing as the Odyssey has great capacity and ability to deliver high loads when needed, welcome the low volt reading of the battery at rest.

 

[DavidT]

interesting...

Also, with a surface charge (checking the voltage a few minutes after the car is off) I only get about 12.55 volts...

I would be willing to bet a steak dinner that my battery is the culprit to my low alternator voltage under a full load... I guess I will swap batteries with the wifes maxima and test it out...


Also, just today while I was getting low voltage with the car running (AC on), I checked the readings with a voltmeter (at the megafuse under the hood). On the battery side, I got 13.44 volts. On the alt. side, I got 13.49 volts. My volt gauge in the a pillar pod read 13 volts... a .5 volt lower than the actual voltage. The fact that the battery side and the alt. side did NOT have identical readings... is this normal?

 

[SHOZ123]

Could be the regulator you have in your alternator too. Your's is a rebuild correct?

I just got a Motorcraft regulator today from Rock Auto. This and some next step up in quality bearings will be going in my old rebuild carcass which had a back bearing go out.

At any rate the my current alternator will deliver 14.2V right after starting and then taper down to 13.7V or so. This is the same regulator that would give me about .2-.4 more volts in the alternator it originally came out of.

 

[DavidT]

yep, mine is a Ford rebuild. Quality is job 1, right?

 

[SHOZ123]

The battery is not what determines the voltage when the car is running. It is the alternator.

 

[SHOZ123]

Also, just today while I was getting low voltage with the car running (AC on), I checked the readings with a voltmeter (at the megafuse under the hood). On the battery side, I got 13.44 volts. On the alt. side, I got 13.49 volts. My volt gauge in the a pillar pod read 13 volts... a .5 volt lower than the actual voltage. The fact that the battery side and the alt. side did NOT have identical readings... is this normal?

What you are seeing is voltage drop due to resistance in the wire. Another way to check is to put one lead on each end of the same wire and read millivolts. This is actually a better way than comparing voltage readings. The lower the better.