Adding Water to Maintenance Free OEM Battery

Well, I have another cheap-skate experience to relate... Only cost about a dollar.

When my engine started to crank a little slowly sometimes, I made the acquaintance of the humongous battery under the back seat. Just as in the poor design of the fuel gauge sending unit, I was a little ticked off to find that the battery was completely sealed on top with no way to check or add water. Add to that the fact that the original battery has been discontinued, and here in the Bay Area the lesser quality replacement runs around $140, and I was quite PO'd.

I've seen a fair number of batteries over the years that were weak simply because the water had evaporated... Filling them back up gave them a new lease on life, and I decided I wasn't going to let GM sell me a new battery until I tried to save the old one.

I took the battery out of the car and set it on the ground with a 2x2 block raising one end. Then I attached one of the rubber vent adapters to the rectangular vent on the high side of the battery. Using a kitchen baster I pumped distilled water into the battery until is started to come out the vent on the low side. I removed the wooden block and let the battery sit level for a bit to equalize the water while I washed down the battery and the cement of any possible traces of acid.

The end result? A year and a half later the engine still cranks quickly, and I only spent a buck on the jug of distilled water. Sometimes the simplest way is the best way - especially if the manufacturer only cares about the item lasting through the warranty period...

2009 Battery Replacement Experience

Well, less than 2 months after my last post, after leaving my parking lights on all night, my battery is a goner. Turns out that "BuRP" only works on the exterior lights if you turn them on manually before turning the ignition off... Now I'll never know how long it could have gone beyond 12 & a half years

I thought I'd share the latest pluses & minuses on the ACDelco 79-6yr replacement, and a couple photos. I decided against the Optima because it costs more for fewer amps, someone here pointed out that the hold-down clamp may stress one of the circular housings, there is no place for the battery thermistor to rest against, and their "non-vent" design still has emergency valves that can vent into the car if the battery overheats/overcharges...

First the minuses: Even though it is the only direct replacement, and the thermistor was their idea in the first place, the posts on the new GM battery stick farther out and the battery case doesn't contact the thermistor package... Hopefully it still picks up heat from the terminal itself. Also, the CCA that fell from the original 970 to 880 is now down to 840. But that's still the same as I had in a 6-litre V8, and plenty for a V6 with a Magnaquench starter.

On the plus side, it's a helluva lot lighter than the original. And amazingly, even here in the Bay Area where everything is expensive, I found one in stock at an independent parts store that carries Delco: $109 plus tax.

Finally, the battery slides in easily and with a couple tidy little mods, the original vent system fits like a charm. After removing them from the "T" connector, a razor blade quickly & cleanly cuts about an inch off of each black tube, leaving one remaining barb. Then, a bit of scotch tape turns the yellow Caution tag into a 'tourniquet' to take the slop out of the rubber strap and keep tension on the end-caps.

See:

http://farm4.static.flickr.com/3319/3568586596_01a83d6512.jpg?v=0
and
http://farm4.static.flickr.com/3648/3568586606_dcfc2bf423.jpg?v=0

I've discharged mine more than a few times, to the point the clock reset. But it comes back and seems to work great as long as I start the car daily.

I will check the water levels when I get a chance.

When did you finally replace yours, Mark?

Late May... Now if you'll excuse me, I just got a package from ZZP...

It certainly can't hurt to top off that battery water...


Oh, and I forgot to add something before: I'm leery of hi-ratio rockers because they did exactly the opposite when we put them on the boat engine. To get a boat going faster you really need more oomph in the high revs because of all the drag. Yet when we changed rockers, we got more bottom end and fuel consumption, but it still wouldn't go over 50 MPH...

It might not hurt, but I just wonder if it's worth doing at this point. It's snowing and 20ºF, and I have an Optima sitting here ready to go when the OEM battery dies. Your car's only a year older than mine, and how long ago did yours need replaced? I'd say I'm doing well at this point.

Yes you're doing well, but that's no reason not to go for the record!
For the price of a gallon of distilled water, I say it's worth topping it off.
I killed mine after a year & a half of perfectly renewed performance by leaving the parking lights on for 2 days...

I'm going for the zero maintenance record!

I think I already have it, but she's still going. And like I've said, already shelled out the $$ so I can stare at this Optima sitting on the shelf.

My '96 has 185K on it with the original bettery. I think I better do the ol water trick soon because I really don't want to shell out for a new battery right now.

96RIVMANN wrote:

My '96 has 185K on it with the original bettery. I think I better do the ol water trick soon because I really don't want to shell out for a new battery right now.

It certainly can't hurt, and if yours truly is original from 1996 then you must have the record for longest battery life.

'97 with 192k - I believe it's the original battery - only thing I've noticed is it's reserve doesn't last exceptionally long anymore. Leaving something on like the radio all day or something will bring it to a slump pretty quick - it always has enough in it to start though - I haven't had to jump it ever.
Any way to check for sure just for shits if it is the original or a dealer replacement?

turtleman wrote:

'97 with 192k - I believe it's the original battery - only thing I've noticed is it's reserve doesn't last exceptionally long anymore. Leaving something on like the radio all day or something will bring it to a slump pretty quick - it always has enough in it to start though - I haven't had to jump it ever.
Any way to check for sure just for shits if it is the original or a dealer replacement?

First off, if you can get a radio / sound system to run all day off reserve battery power you are doing exceptionally well in any vehicle.
Second, I believe there is a date code etched into the battery case, some sort of code that I do not know how to decipher.

turtleman wrote:

'97 with 192k - I believe it's the original battery

Then you're another candidate for the fill-up I posted above... You can do it when you put in the new RCA cables.

Rickw wrote:

turtleman wrote:

'97 with 192k - I believe it's the original battery - only thing I've noticed is it's reserve doesn't last exceptionally long anymore. Leaving something on like the radio all day or something will bring it to a slump pretty quick - it always has enough in it to start though - I haven't had to jump it ever.
Any way to check for sure just for shits if it is the original or a dealer replacement?

First off, if you can get a radio / sound system to run all day off reserve battery power you are doing exceptionally well in any vehicle.
Second, I believe there is a date code etched into the battery case, some sort of code that I do not know how to decipher.

I'll check it out when i pull the seat to run the new RCA cables.

I kind of used poor wording. If I leave the radio on for a few hours which I tend to do while working on the car, It will drop a good bit below 12v. Even with 11v or so, it still starts. It will crank pretty slow but the battery keeps the current coming even if it doesn't fire up right away - benefit in having a large battery. With most car batteries I test for customers or my own past vehicles, once the battery has fallen to 11v or so after being drained, it's got nothing left and you're gettin a jump.

turtleman wrote:

With most car batteries I test for customers or my own past vehicles, once the battery has fallen to 11v or so after being drained, it's got nothing left and you're gettin a jump.

This is why i don't like the fact that the factory set-up on many a Riv only provides a charging voltage of 13.4 to 13.8 volts.
I've added a #4 cable from the Alternator output post to the underhood terminal that feeds the battery and starter.
This has helped eliminate the variable HVAC fan speed at idle and Turn Signals flashing at different rates from idle to above idle and other things.
Now I just need to add the resistor to the thermistor sense wire at the alternator and give me 0.6 more volts at idle.
Then all will be right with the world. Or at least the car should be able to handle the addition of some amplifiers in the spring.

Rickw wrote:

This has helped eliminate the variable HVAC fan speed at idle and Turn Signals flashing at different rates from idle to above idle and other things.

That is really annoying. Especially if you have the rear defroster on. The fan goes from high speed to low whenever you step on the brakes and come to a stop. Not only that, I noticed that if I press my window switch while at idle and the window is all the way up, the RPMs drop and the engine starts to run rough. I realize the Riviera has a lot of electrical doodads on it and the alternator is 140 amps, but if it isn't delivered the right way it doesn't do much good.

Get approximately 4 feet of #4 battery cable and one 5/16" terminal end and one 3/8" terminal end.
The 3/8" goes to the under-hood connector and the 5/16" goes to the output stud on the back of the alternator.
The local independent parts store I deal with stock's the battery cable in bulk and sells the individual cable ends.
They also have the tool to crimp the cable ends on.
So I did the job right in front of their place.
He let me take the box of 50 ft of cable out to the car and I ran the cable parallel with the existing wire that comes off the back of the alternator, over the SC and around to the terminal block that feeds the battery and starter. They also had the cable cutters. And he threw in some black wire ties to neaten everything up.
All said and done was about $10.00 and I noticed an improvement right away, especially now that it's cold and I'm using all the high draw stuff - like the seat heater, rear defrost, HVAC fan on high quite a bit, etc.
I don't have the fan speed slowing down at idle anymore as well as the fluctuating turn signal speed.
Everything is stable now. All that is remaining to do is install the resistor in the thermistor wire at the alternator to add 0.6 volts.

Rickw wrote:

Get approximately 4 feet of #4 battery cable and one 5/16" terminal end and one 3/8" terminal end.
The 3/8" goes to the under-hood connector and the 5/16" goes to the back of the alternator.
The local independent parts store I deal with stock's the battery cable in bulk and sells the individual cable ends.
They also have the swedging tool to crimp the cable ends on.
So I did the job right in front of their place.
He let me take the box of 50 ft of cable out to the car and I ran the cable parallel with the existing wire that comes off the back of the alternator, over the SC and around to the terminal block that feeds the battery and starter. They also had the cable cutters. And he threw in some black wire ties to neaten everything up.
All said and done was about $10.00 and I noticed an improvement right away, especially now that it's cold and I'm using all the high draw stuff - like the seat heater, rear defrost, HVAC fan on high quite a bit, etc.
I don't have the fan speed slowing down at idle anymore as well as the fluctuating turn signal speed.
Everything is stable now. All that is remaining to do is install the resistor in the thermistor wire at the alternator to add 0.6 volts.

So you're essentially upgrading the vehicle grounding point from the alternator? Sounds pretty simple to do. Now why didn't GM do this to begin with? Did you notice any sustained voltage increase after the upgrade?

I ordered my MSD 5111 160 amp alternator today should be here with my Cobalt D-Pic gauge at the begining of February.(Damn B/O's)I hope it will rectify my stereo gremlin. Soon as I turn it up to a certain point it draws so much power the amps and speakers cut out because it clips the signal. The Digital D-Pic shood look sharp with my digital cobalt boost/vac gauge tucked in where the ashtray was. I think thats the least hassle place to install them while keeping the "factory look" of the flip down covers of the Riv.

The new cable ground idea sound pretty good, I will alter mine when I install the MSD.

P.S. Its snowing for the 3rd day in a row here, and the forecast calls for three more dayz of it. Why in gods name did I sell my snowmobile last year???

GMFreak8 wrote:

So you're essentially upgrading the vehicle grounding point from the alternator? Sounds pretty simple to do. Now why didn't GM do this to begin with? Did you notice any sustained voltage increase after the upgrade?

No, I didn't add any cable for Ground yet, just positive from the Alternator output to the Terminal Block. The existing wire is a #8 awg which can't possibly carry enough current from the alternator to the battery connection under the hood. So essentially all I did was provide additional cable to allow the current to flow to the under-hood battery connection which also powers some of the accessories from the relay and fuse block under the hood.
I did not measure the voltage immediately before adding the cable, but from what i recall my battery voltage with engine running at idle before adding the cable was about 13.0 to 13.4 volts. Now I'm reading a more consistent 13.8 ish. So I have noticed a slight increase with less variation at idle. After I install the diode /resistor I mentioned I'll get another 0.6 volts from what everyone else that has done it says. That should put me at a comfortable 14.4 volts. Ideal for running amplifiers.
I also want to run an additional ground cable (#4 awg) from a mounting bolt on the alternator down to a point on the chassis where there is an existing ground wire from somewhere else. I cleaned that ground connection up and sealed it before the cold weather settled in. It can't hurt to provide an addition ground path.

Rickw wrote:

GMFreak8 wrote:

So you're essentially upgrading the vehicle grounding point from the alternator? Sounds pretty simple to do. Now why didn't GM do this to begin with? Did you notice any sustained voltage increase after the upgrade?

No, I didn't add any cable for Ground yet, just positive from the Alternator output to the Terminal Block. The existing wire is a #8 awg which can't possibly carry enough amps from the alternator to the battery connection under the hood.
I did not measure the voltage before and after, but from what i recall my battery voltage with engine running at idle before adding the cable was about 13.0 to 13.4 volts.
So I have noticed a slight increase. After I install the diode /resistor i mentioned I'll get another 0.6 volts from what everyone else that has done it says.
I also want to run an additional ground cable (#4 awg) from a mounting bolt on the alternator down to the frame rail as well. It can't hurt.

Ahh, ok I get ya now. I misread it. What's the gauge of the wire running from the battery to the terminal under the hood?

NOTE: I misread your question, look to the post below for the proper answer.

The factory wire from the alternator to the terminal block is only a #8 awg. With an alternator that is capable of putting out 140 amps obviously that cable is undersized.
I left that cable attached and added the additional #4 awg cable. So with the 2 of them it should allow the alternator to provide it's current much easier to the battery and the accessories that are powered from that terminal block under the hood.

You were asking what the diameter of the cable is that runs back to the Battery from the terminal block.

It is very large on my car. My guesstimate would be about a 3/0 awg. I believe it is capable of carrying all 140 amps from that point back to the battery.
So the big choking point is from the alternator to the terminal block.
Initially I thought i was going to have to increase the size of the cable running back to the battery, but after looking more closely i don't have to.

That sounds like another cheap and easy mod, and IIRC you've already replaced your battery, right Rick?

Just to play devil's advocate, Kyle's complaints are typically indicative of a low battery or a low-output alternator. I certainly know that GM makes mistakes, but technically speaking, a 5' long, 8AWG wire can carry 100 amps - and 100 amps is mostly the max of what I'd expect out of a 140 amp alternator... It might make 140 amps if it's cold, and the engine is spinning 4 grand, but at a hot 2,000RPM cruise (or all that stop & go idling around town) it's not gonna' put out as much current.

On my '97, both the new battery and the refilled OEM battery had very little voltage drop at idle. As far as I know, I have the original alternator, so the stock setup seems enough to handle all the original options. The other day I noticed the scanner readout at hot idle was 13.9 to 14 volts.

I'd top off my battery if it was more than 6-8 years old, and then I'd check the voltage at the alternator terminal itself, and at the jump-start terminal, to see if I was losing anything to that charging wire...

After some thinking, I decided I would try to examine my OEM 7-year battery, now 12 years old. If needed, I would add some water to the cells, but I didn't want to do it blindly, without knowing what was really going on inside. For all I knew, the battery was fine - it had served me fine so far, and still starts the car each 15ºF winter morning. No, it wouldn't let me turn my headlamps on for an hour, or listen to the stereo all day, but I rarely do either, so no big deal. It's a 12-year old battery, what do you expect?

So, with a replacement Optima Red Top battery sitting idle, I decided to approach this scientifically by trying to open up the top of the battery for the purpose of learning how it worked. If I broke it, no harm - the Optima would go in. Not intending to discredit Eldo's method, but I just wasn't comfortable pouring water in the vent tube and hoping for the best, for a few reasons:

1) the cells could have enough electrolyte - there's no (easy) way to check on a maintenance-free battery like ours.

2) toping off cells technically doesn't hurt the battery, but later on when the battery gets warm (during charging, or seasonal change), the excess water (now acidic electrolyte) could expand and overflow into the vent tubes, or worse, under the seat.

3) there's no guarantee that water introduced to the vent on the elevated side will make it into the cells before exiting the vent on the low side. It's assumed, but you can't be sure.

4) if some water made it into some cells, there's no way to guarantee all cells received equal amounts, because it can't be measured.

Well here she is, my green-eyed lady, living under the rear seat looking just as new as in '97:



The built-in green eye, a hydrometer that tells you electrolyte levels are in the range of a healthy charge. Looking nice and green!:



It's important to note that the eye only monitors one of the six 2v cells inside the battery. Since all the cells run in series to produce 12v, they all need to be just as healthy as the one that can be checked. The way this works is a small green ball floats in the electrolyte. If charged, the specific gravity causes the ball to rise and fill the eye with green color. If the electrolyte is not charged, its specific gravity causes the ball to sink, making the eye appear dark. If the electrolyte (water) level goes too low, it will also cause the ball to sink, making the eye dark.

This could lead us to the conclusion that if the battery has no leaks, and the water level in the green-eye cell is okay, that the levels in the other cells would also be adequate, since the water should evaporate at the same rate. This doesn't mean there couldn't be a problem with one of the other five cells, but it does tell us the green-eye cell is good, and the other cells probably have enough electrolyte to do their jobs.

But to know for sure, I needed to see into the battery. Unfortunately, the decal on top was not covering the openings to fill the cells, as is the case with some maintenance-free batteries. However, I did notice there seemed to be a removable panel where the vent tubes go, and I wanted to see what was underneath.

Here's the battery, out of the car. Beautiful case, no cracks or leaks to be found. The removable panel is on the back side, where the green eye lives:



I started to pry at it with a couple medium to large flat head drivers. It was a little tough, but finally it popped up!



As I worked my way toward the middle, the cover popped off the cells one-by one. This was not easy, and I could tell the cover was not meant to come off. Each of the cell openings were glued or welded to the cover, and it was also permanently bonded to the ribs dividing each top compartment:



You can tell that every single rib and cell opening had been bonded to the cover, but I carefully continued to pull it up. I noticed there were two areas (circled below) in each cell that are recessed, so as to allow venting of gases from the cells, into the vent tubes. These recesses are very small and very high, so it's very hard for electrolyte to spill from the battery, but hydrogen gas would have no trouble finding its way out:



Notice how there is a recess (large circle) bridging the main compartments, but the recess that actually vents each cell (small circle) is very tiny, and must go through a secondary compartment before entering the main compartment. This is designed to keep electrolyte in while letting gas out.

Here's another closer view from the side:



And here's the green eye (hydrometer) seen from below. You can almost see how it functions in this pic:



With the cover finally removed, you can see all the cells from the top, and the electrolyte levels, which are all consistent, and rather high. I measured with a screwdriver and determined the levels were ~1.25" down from the top opening of each cell:



Here is a new $5 tool, a hydrometer that lets me check the charge of each cell. It's a simple float mechanism that works kind of like a coolant tester:



And here is the result of the electrolyte test. The water was crystal clear, and all 6 cells checked identically:



For reference, here's the same test using distilled water:



Since I did have the opportunity, I added a very small amount (4 tablespoons) of distilled water to each cell, bringing their levels to within ~1.00" of the openings. I did not want to fill them so high that they could spill during a sudden stop or hard turn.

Finally, I had to get that cover back on. It snapped back into place nicely, but knowing the cells were no longer sealed, I wanted to ensure there would be no spills should the battery get tipped during install, so I used clear packing tape to wrap the cover to the battery. I wrapped it very tightly, all the way around, two times. This works to compress the cover down, and it forms a seal that should keep the gas exiting only through the vent tubes.



I reinstalled the battery with no problems. We'll see what happens!

Things I learned:

• After 12 years, the electrolyte levels in all cells were identical and acceptable at 1 1/4" down from top.

• All cells were consistently charged and had better than optimal charge readings, as measured by the hydrometer.

• The cover being sealed to each cell opening with such a small hole to each cell, guarded by dual compartments, it is unlikely much if any distilled water could be introduced to the cells by flooding the vent tubes. What likely happens is the water fills the first main compartment, then overflows to the next, which then cascades until the water comes out the other vent tube. In short, the same amount of water that goes in comes out. At best a few drops of water might reach the first cell, but not the middle or last ones.

• I probably should have just left things alone. I'm fairly confidant the battery will continue to last through 200k miles, and maybe longer. It received a little added water (1/4" increase in level), but it really didn't need any, imo.

Hopefully this info will be useful to someone, but I would not go through the process again, and I don't encourage anyone to do the same to their battery unless you are curious and careful (wear gloves and safety goggles, don't smoke!), and only if you are willing to accept the possibility that yours might break - the cover was not intended to come off, ever. It tells you to "not open battery" right on the top, so do at your own risk.

Cheers, AA