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Topic: How do you check battery electrolyte level? (Read 930 times) previous topic - next topic

How do you check battery electrolyte level?

I have thought a lot about this.  Our house batteries are pretty hard to get to - the "close" cells have the cables obstructing the caps.  It is nearly impossible to see into the rear cells.

I came up with a solution that has worked for me.  I got a piece of icemaker supply hose about four feet long from the stuff in the garage (about any clear small hose would do), and ran a ring of masking tape around one end, about an inch from the end.  I place the taped end in the cell with the tape half-way into the cell opening, and the other end in my mouth.  The tape ring is an indicator to show that the end of the tube is near the bottom range of the electrolyte level rings in the cell.  Then I blow - if I hear bubbles I know the electrolyte is within range.  If no bubbles, I use the tube as a pipette to draw water from a jug of distilled and dispense it into the cell.  Dipping the tube into the distilled water removed most of the electrolyte from the end.  The tubing is clear, so I can see the level of the water as it rises into the tube and avoid drawing the water and a bit of electrolyte into my mouth.

This is the best simple and cheap solution I have found.

oldMattB
Matt B
1998 u-320

Re: How do you check battery electrolyte level?

Reply #1 –
Matt,

Another option is to use a small mirror and flashlight to look into the cells.

And if the cables are obstructing access to the cells, relocate them.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: How do you check battery electrolyte level?

Reply #2 –
I tried that, but after I get a mirror, a flashlight, and my big hands and arms in there, there is no room to see.  I was able to use this method on our old coach, but on our current one I just couldn't see enough.

I thought of adding a distribution lug beside the batteries so I could have a single cable coming from each terminal rather than several, but a piece of free pipe seemed a lot easier.  Is this what you meant by relocating the cables?  The problem is the terminals are near the cell caps, and that is at the front of the battery.  Reorienting the batteries with the terminals to the inside would make the cell access easier, but would make connecting the cables and inspecting the ends nearly impossible.

Am I missing something?

oldMattB
Matt B
1998 u-320

Re: How do you check battery electrolyte level?

Reply #3 –
I invested in those auto fill pumps that replace the caps on the batteries. It takes me 1 minute per set to make sure they are full. Pricey at 60 bucks per pair of 6 volts but for me it was WELL worth the money. Drop the tube end into a gallon of distilled water, pump until the bulb is hard, cocktail time.
1994 U280, Build 4490
Deming, NM.

Re: How do you check battery electrolyte level?

Reply #4 –
Clever. I have the exact same problem and had yet to come up with a good solution. I'll have to give this a try.

I assume you tested your tape mark on a cell you could see to determine the correct depth? I'm thinking I would just mark the tape at the correct depth with a marking pen.

I don't understand what you mean by this though...
Quote
Dipping the tube into the distilled water removed most of the electrolyte from the end.

Thanks for the cool tip. Karma for you!

see ya
ken
The selected media item is not currently available.ken & dori hathaway & Big Agnes
🍺1992 U300 GrandVilla WTBI #4150 FOT FBP 2011
✨6V-92TA DDEC Parlor Coach 350HP Series 92
🏁2011 Nissan XTerra Pro-4X

Re: How do you check battery electrolyte level?

Reply #5 –
Quote from: kenhat –
Clever. I have the exact same problem and had yet to come up with a good solution. I'll have to give this a try.

I assume you tested your tape mark on a cell you could see to determine the correct depth? I'm thinking I would just mark the tape at the correct depth with a marking pen.

I don't understand what you mean by this though...
Thanks for the cool tip. Karma for you!

see ya
ken

Each cell has a plastic affair, hole in the bottom, open at the top, with a slot down part of the side.  The electrolyte should be between the bottom hole and the top of the slot.  The tape roughly reflects the range of the slot.  I can use the width of the tape to judge where in the range the electrolyte is.

Regarding the quote:  Should you draw water into the tube without a "swizzle and a blow,"  you might get some acid in your mouth if you draw too far.  From my recent experience it is bitter, but probably no worse than stomach acid.  (It would be acid partially diluted by water.)  I found that if I dipped the tube into the water and blew a bit, the acid was mostly removed from the inside of the tube before I drew.

oldMattB
Matt B
1998 u-320

Re: How do you check battery electrolyte level?

Reply #6 –
I cut two hardwod sticks, the size of Ice Cream bar sticks in both one ends I cut a notch for full, on the other end I cut another notch for "add" of pure distilled water. Two sets. (always carry a spare(anything))

Bill chaplin
1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: How do you check battery electrolyte level?

Reply #7 –
Also, there is a product called Hydrocap which replaces your cell caps. They reduce gassing dramatically so you can go a very long time before having to add water. They are a little pricey; I think we paid $135 for our four Trojan 105s (12 caps).
jor

Here's a link to their site. They are in Renton, Washington (my old stomping grounds)
Hydrocap | Information
93 225
95 300
97 270
99 320
 

Re: How do you check battery electrolyte level?

Reply #8 –
Quote from: Bill Chaplin –
I cut two hardwod sticks, the size of Ice Cream bar sticks in both one ends I cut a notch for full, on the other end I cut another notch for "add" of pure distilled water. Two sets. (always carry a spare(anything))

Bill chaplin 

Earlier someone here, Bill I believe, posted that he had notched a small diameter rod with two notches, one for low level and one for full level.  I don't remember the dimension for each notch from the end of the rod.  (I hope someone remembers the dimension for each notch.  The dowel rod I use is in the coach in storage so it is not readily available for me to measure.  I will be happy to measure each dimension when I am at the coach next time if needed.)

I then got a very small diameter plastic rod approximately 6 inches long.  I pull the battery carrier out as far as it will go, remove one cap at a time and insert the plastic rod into the cell until it rests on top of the plates. I then remove the plastic rod and hold it against the wooden dowel rod to see where the level is on the dowel rod.  I do this for each cell. If I have to add water, I use a kitchen turkey baster and add distilled water to each cell, even the back cells using the turkey baster.

This works well for me.

I also had significant problems with the cables blocking access to the front caps.  I finally was able to loosen the bolt which fastens the cables to the battery connector and I was able to rotate the cables up enough to be able to reasonably easily remove each front cell cap, check the fluid, add fluid if required and replace the cap.
Morris and Janice
1997 U270 36'