Chassis batteries

[jestal]

Under the heading of neglectful coach owner I pulled the chassis batteries I have been having trouble with and took them into a good battery shop for testing/revival hopefully. Turns out they were Interstate replacement and are actually only 3 years old. In removing the maze of cables and connections I discovered that the terminals were relatively loose and some corrosion between the various connectors on the terminals. Cleaned everything up, wirebrushed the battery box which was surface rusty in spots. Cleaned it out thoroughtly and painted with Rustoleum. All terminals need further wirebrushing and TLC. Some ring terminal were wound 360 degrees around from inept tightening of the terminals. The shop is doing a thorough recharge and desulfating cycling o the baaaovernight and load testing tomorrow.

Several things to be aware of: the chassis batteries come out easier than you think....it just takes some time. Everything in the battery box is pretty dirty from road dirt from the open forward facing hole that the cables route thru. Entegra needs to come up with a much better idea here and some better cable terminating procedures and better control of the terminal locations and avoid the stacks of terminals on the same post. I'm sealing the cable entry hole with a plug of closed cell foam cut to fit around the wire bundles and a rubber flap on the DEF tank side of the opening. All the corrosion issues were mainly on the forward most terminal of the front battery. Not terrible but definitely needed attention. This is an area that desires a little more attention in the future from me. From 3 feet away it looked dusty but Ok but once the batteries were out it was obvious that the major problems are hidden and hard to see.

One more thing to put on the regular maintenance check list.

[bill2011]

Thanks for that information Jestal. I will have a look at mine in 6 months time and clean. One thing I am wondering but pertains to house batteries. When I asked about how to access these batteries which on the 2017's are hidden behind a panel the delivery tech told me that these require no owner maintenance whatsoever. Can this be so?

[vsheetz]

Originally Posted by bill2011

Thanks for that information Jestal. I will have a look at mine in 6 months time and clean. One thing I am wondering but pertains to house batteries. When I asked about how to access these batteries which on the 2017's are hidden behind a panel the delivery tech told me that these require no owner maintenance whatsoever. Can this be so?

Yes, likely AGM batteries. Sealed, no adding water.

[jestal]

not familiar with a 17 but I would at least take a look at them and confirm they are staying clean and dry. The road dirt and moisture caused all my terminal corrosion and corrosion of the battery box itself. The interstates ate sealed wet cell no maintenance batteries, too. No AGM but nothing to do to them but keep the terminals clean and tight. The road spray entering did not help them.

[brobox]

Al,
great heads up post. While at Camp Entegra, house battery charging came up where many of us inspected our batteries. Many thought AGM batteries required no maintenance and had never cleaned the terminals. Two sets of batteries did not have a protective coating on them from production and were in need of cleaning. ........dead lead on the terninals. Good post regarding battery cleaning, even AGMs

[jestal]

The two chassis batteries I have are not AGM's but normal wet 12 volt batteries albeit they are sealed and of the maintenance free type so no water needs to be added. They do have a common vent hole, though and no hose or anything to route the fumes out of the battery compartment so some of the corrosion may have come from that. They are going back in with a vent tube routed out of the compartment.

I would not wait to check your chassis batteries as there are stacks of ring terminals and/or several large crimp style cable terminals stacked under each f the hold down nuts. With the stacks of terminals (which is really not a good idea.....) the clamp load of the nut gets dispersed and disappears with time. They "seemed" tight with a small wrench but it was the stiction under the head of the nut and corrosion holdin them. Once I applied a itny bit of torque to remove them they were only finger tight.

I'm using some washers and dielectric grease to reassemble the terminals to keep the moisture out of the connections and keep the ring terminls from collapsing together.

I can't wait to get started on the house batteries as I can only imagine what those connections will be like when I take them apart fo examination.. Much more weather proofing is also in order there, too.

[Cruzer]

"Sealed" flooded batteries are a bit of a misnomer. While it's true that you shouldn't have to worry about adding water, they aren't sealed in the aspect that they vent hydrogen and acid. The hydrogen gas is explosive so they need to be in a vented compartment. The acid does cause corrosion so if you seal the area off too tightly the acid will hang around the terminals and corrode them so make sure you do have some makeup air. CRC makes a good battery terminal protectant spray that helps prevent corrosion. It doesn't eliminate it but it does help substantially. Also, you can get those red and black felt washers at any auto parts store that are filled with a chemical that resists corrosion. Those are very effective and slip over the battery post before you add the clamp.

My guess is that the DEF is most likely not helping, which is why the front battery had more corrosion. If you are going to do any sealing I would concentrate on that area but leave the back more open.

[brobox]

Al, I mentioned the AGM as I found out at Camp Entegra that none that were in PJ's class with me had checked there AGM's in 2 years. Not only the wet cell Chassis batteries need to be checked, but the AGM are not "forget about them" type of batteries. There were statements made that their charges were not lasting as long as they did when new. First thing I would check would be battery terminal condition. You brought up a very good reminder, all of the batteries need to be checked at least once a year.

[jestal]

Originally Posted by Cruzer

"Sealed" flooded batteries are a bit of a misnomer. While it's true that you shouldn't have to worry about adding water, they aren't sealed in the aspect that they vent hydrogen and acid. The hydrogen gas is explosive so they need to be in a vented compartment. The acid does cause corrosion so if you seal the area off too tightly the acid will hang around the terminals and corrode them so make sure you do have some makeup air. CRC makes a good battery terminal protectant spray that helps prevent corrosion. It doesn't eliminate it but it does help substantially. Also, you can get those red and black felt washers at any auto parts store that are filled with a chemical that resists corrosion. Those are very effective and slip over the battery post before you add the clamp.

My guess is that the DEF is most likely not helping, which is why the front battery had more corrosion. If you are going to do any sealing I would concentrate on that area but leave the back more open.

mark, I agree. The vent hole on these batteries is not readily obvious
that is why I mentioned the fact that I was adding a hose to the vent hole to route the hydrogen and any acid fumes outside the compartment...similar to what is done with car batteries like this mounted inside the passenger compartment. The hole accepts a small plastic vacuum tee inserted into it which makes the bend to route the hose downward even easier!

Believe it or not the terminals were sealed with the red battery terminal sealer spray so at first glance I thought they were fine and did not want to disrupt the coating but upon disassembly the coating was doing more harm than good. It was poorly applied and was holding moisture in one area! I'm not sure I'm going to try using it when it goes back together as the terminals are not accessible to coat them correctly.

Do your other coaches have a rubber mat glued to the ceiling of the chassis battery tray? Mine has that and it has fallen off due to the glue failing (another Entegra opportunity to improve.) I see no reason for it unless it is put there to keep someone from grounding a wrench to the bare metal so I was debating replacing it.

[Cruzer]

Originally Posted by brobox

Al, I mentioned the AGM as I found out at Camp Entegra that none that were in PJ's class with me had checked there AGM's in 2 years. Not only the wet cell Chassis batteries need to be checked, but the AGM are not "forget about them" type of batteries. There were statements made that their charges were not lasting as long as they did when new. First thing I would check would be battery terminal condition. You brought up a very good reminder, all of the batteries need to be checked at least once a year.

While at Spartan, Big Mike noticed dust on top of the AGM house batteries and told me they should be cleaned. Dust and road dirt does get in there when driving and if it gets damp it is actually conductive so that it causes current to flow from the negative to positive post on the battery, which is why GM started to go with side terminal batteries years back. I generally clean them with a quick spray from the pressure washer but Mike told me that's not very good. Even though the AGMs are basically a sealed battery, there are valves on the top of them to allow for thermal expansion as the battery changes between hot and cold. The pressure washer (or garden hose spray can get in the valves and into the battery cavity, which is especially not good on an AGM. He told me that using a spray bottle of the original Windex with Ammonia D (not the other versions currently being offered) and a wipe down with paper towels is the best way. I now carry a bottle of Windex in my arsenal of chemicals, sealants and lubricants.

[Cruzer]

Originally Posted by jestal

......Do your other coaches have a rubber mat glued to the ceiling of the chassis battery tray? Mine has that and it has fallen off due to the glue failing (another Entegra opportunity to improve.) I see no reason for it unless it is put there to keep someone from grounding a wrench to the bare metal so I was debating replacing it.

My guess is that it was there to prevent a short in the event a battery hold-down failed and the battery contacted the steel roof.

Foam can be hard to adhere when hanging upside down. It just absorbs too much and gets heavy. I use 3M Safety Walk in numerous places. In fact I just ran about 40' of the gray 18" wide stuff on the roof of our coach to keep me from slipping when I have to shovel snow off of it. This stuff is thin and sticks very well. A piece of that on inside of the battery box's roof would work well. Or something similar that is thin and non-absorbent,

[Matt D]

FYI, the '17s are equipped with 2 or 4 L16 AGM batteries manufactured by Discover Energy, and distributed by Harris equipment (?) to Entegra.

The Aspire gets 2 L16s, while the Anthem and CS get a quartet of these batteries. Each battery is fairly large and very hefty at 115# each, so removal requires some effort.

Access to the house battery compartment is midship on the DS of the coach. In our case, the compartment is just in front of, and slightly inboard of the holding tanks. There is a carpeted panel inboard of the heavy draw Buss switches, remove 8 square head screws and remove the panel.

Interesting thing is the space and hardware (except series/parallel battery cables) are in the Aspire to accommodate the 2 extra L16s if you're a hardcore boondocker. The only "work" involved would be to relocate the floor bracket for the tiedown. Aside from the $1300 price tag, this is one of the easiest mods possible. An Aspire would go from 390AH to 780AH.

Expect 6-8 hours of inverter time before you get an unmodified Aspire uncomfortably low. I would estimate a 4 battery Aspire could potentially achieve twice that time. These estimates are based upon approximately 25amp per hour, or a fridge, a few lights, and some TV usage.

Regardless of battery type, some maintenance is prudent. As noted, terminal ends and cables still require attention, even with AGMs.

The '17 uses a completely sealed off house battery compartment.

The chassis batteries are unchanged from the preceding years' "open" design. According to EC, the chassis battery compartment must breathe for the chassis batteries and DEF tank. While I agree conceptually, I believe some improvement can be made such as the previous mention of closed cell foam.

I've been neck deep in our coach for the last week and the batteries were at the top of the list until I flogged them a little and realized they are very decent batteries.

Best Regards,

-Matt

[jestal]

mark, thanks for the reminder about the dust and dirt on the house batteries and the Windex tip.. I'll take a few rolls of paper towel and windex with me when I go to the coach to put the chassis batteries back in.