time to check your "maintenance free" battery

riverwolf

New member
First of all, the OEM Panasonic appears to be a beast of a battery...too bad we can't get a replacement in the States. While it helps that I have a relatively battery recharge friendly commute, I think it's still a testament to Panasonic that the OEM battery in my 06/03 build 4Runner is still going strong.

Anyway, doing various routine maintenance bits in anticipation of family vacation to the Smokeys, I noticed the battery sight glass said "add fluid". Kind of interesting since there's a sticker right next to it that says "maintenance free". :D Long story short, I was able to add almost 1/2 gallon of distilled water.

Caveats: there's a clear sticker covering the vent ports. You should be able to find the edge of it using a flat blade screw driver or knife. I actually grabbed my biggest flat head and started turning the maintenance ports, which caused the sticker to crinkle. However, you can munge up the port cover this way if you apply pressure on the slot with the gas vents in them...DAMHIK. :bash:

I'm not sure where to actually fill the level to. I tried to go by the "high water" marks I saw in the maintenance tubes. However, when I slapped a charger on it after adding water, I got a little overflow from the cells closest to the positive terminal. After letting it sit for a bit, I reconnected the charger and once again got a little more overflow from the first cell (closest to the positive terminal). Granted, it is about 95
 
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The pics here may help with the 'full' mark. They're of my '07 so the marks may be different. And :iagree:, wish we could get the Panasonics here.
:cheers:
 
riverwolf said:
First of all, the OEM Panasonic appears to be a beast of a battery...too bad we can't get a replacement in the States. While it helps that I have a relatively battery recharge friendly commute, I think it's still a testament to Panasonic that the OEM battery in my 06/03 build 4Runner is still going strong.

I agree. The Panasonic battery that can standard in the 4Runner is a beast. My '04 still has the origingal Panasonic battery.
My 4Runner sits for long periods of time between uses because it is used for towing and long trips and not my daily commute.
Because of that, I use a "Battery Tender" charger on it.
This charger is different from "trickle" and conventional chargers because it has a number of different charging modes that are controlled by a microprocessor.
These various modes prevent battery damage that trickle and conventional chargers can cause.
I have used the "Battery Tender" in my show/antique/classic cars for 9+ years now.
During that time I have not had to replace ANY of the batteries that a "Battery Tender" is charging.
I have also added VERY little water to any of these batteries over that timeframe.

For anyone that has a 4Runner that is used occassionally (like mine) I Highly recommend getting & using a "Battery Tender" charger.

Originally posted by riverwolf Even though the sight glass is still reading "needs recharge" after topping off the water, my DMM read a little over 13 volts directly across the terminals. Now, I'm curious to see just how long this battery will last.

Just wondering if you measured the battery's volts while you cranked the engine?(ie a load test so to speak)
I have always thought that measuring the volts, how low they dipped during cranking and how long it took
the volts to come back to normal was a better indication of a battery's condition.

Personally, I have had batteries in the past that measured 13-14 volts without the cranking/measuring test.
That gave me a false sense of security that the battery was fine and then it would not start the car.

Also it is my understanding that when one adds a lot of water to a battery it may, in fact, negatively impact it's charge level (ie need to be charged).
 
My Panasonic lasted for 3.5 years and 50,000 miles. I never had a problem with it, but the battery failed a load test. I would rather be safe than sorry.

This past week, a parking garage decided to test the limits of my new battery. They accidentally left my key in the ACC position for 2 hours. I only caught it because I left something in the truck and it was parked up front. I turned the key, and it fired up with no problem.
 
CJ3Flyr said:
The pics here may help with the 'full' mark. They're of my '07 so the marks may be different. And :iagree:, wish we could get the Panasonics here.
:cheers:

Yeah, I saw the min/max lines on the side of the case. Unfortunately, I couldn't tell where the fluid level was relative. Maybe if I'd pulled the battery completely out of the truck and put a work light on one side to shine through the shell.

A little more Google time today turned up a diagram showing the proper fill level when viewed through the fill ports. When you look inside the fill ports, there's a tube that extends down about 1.5" or so into the battery. The bottom end of the tubes are slotted. The fluid level should just reach those slots. I think I may have covered up a bit too much of those slots, which resulted in a bit of weeping until the cells lost enough water.

Apparently, at one time when battery maintenance was the norm, there was a dispenser that fit into these tubes and released the correct level automatically, much like a fuel filler's auto shutoff.

-Brent
 
Re: Re: time to check your "maintenance free" battery

charlier180 said:
{snippage}
Just wondering if you measured the battery's volts while you cranked the engine?(ie a load test so to speak)
I have always thought that measuring the volts, how low they dipped during cranking and how long it took
the volts to come back to normal was a better indication of a battery's condition.

Personally, I have had batteries in the past that measured 13-14 volts without the cranking/measuring test.
That gave me a false sense of security that the battery was fine and then it would not start the car.

Also it is my understanding that when one adds a lot of water to a battery it may, in fact, negatively impact it's charge level (ie need to be charged).

I measured it "no load/engine off" straight across the terminals. IIRC, anything over 12.6v or so is considered healthy enough that one shouldn't feel a sense of impending doom...obviously there are no guarantees with a rule of thumb. That's why we all keep an emergency kit with jumper cables in the vehicle, right? Hopefully, it's just there to assist others, but every once in a while we might need to help ourselves.

It does stand to reason that right after adding fluid, the charge could be weaked a bit until the solution is properly "mixed", but I did pop a charger on it until it started to weep a bit due to a slight overfill...by then, the charger was indicating better than 75% charged. A couple of short drives later and the sight glass was reading "OK" again, so charging alone may not mix the solution enough to float the indicator; "agitation" may be needed as well.

-Brent
 
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riverwolf said:
Yeah, I saw the min/max lines on the side of the case. Unfortunately, I couldn't tell where the fluid level was relative. Maybe if I'd pulled the battery completely out of the truck and put a work light on one side to shine through the shell...

No need to pull the battery. Shine the work light from the front and look at each cell from the rear (next to the fuse box). At first glance you may think it is low with the light coming through but that is above the plates. Rock the truck to see where the level actually is.
Mines an '04 and the level is 1/3 down from max (2/3 up from min.)
 

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