Max. battery in front storage compartments

[Harrysheets]

Vehicle: 1986 Sovereign side bath.
Topic: Max. possible size of batteries in my front door access boxes
What is the max size that fits? Group 24, 27 or 31 AGM
Travel style = typically parks w/ hook ups – 2 night boon docking max., with small generator

I am trying to cram as much as possible into the existing two plastic battery boxes integrated into the front. It is so tight in these boxes I decided to lay it out in CAD.

The side view shows a working area of about 13”L by 9 1/8”H (at back of box). Since the box has a 1” draft you have about 10” of height at the front. Internal box width appears to be wide enough for these group sizes and leaves room for wires.

Initially I was looking to fit the Concorde Lifeline AGM GPL-31XT as it was well recommended, has the most Ah, US made, etc… After calling Concorde I found out a few things. A) Drawings on the web sight were out of date and did not show the newest packaging design. Although the new plastic case is slightly less tall the automotive type posts are slightly higher. B) The posts increase the height to 9.51” (slightly less w/o top bolt [-0.32]). The group 27 with posts might just fit with a height of 9.47” (9.15” w/o bold). This is about what my CAD drawing shows available with the group 27 slid to the front. These automotive posts are threaded in and held in place with red Locktite.

After doing some further research I found that the Concorde Sun-Extender battery comes in the same 27 & 31 cases but does not have the tall automotive post installed. Concorde staff also said the PVX-1040T was very similar to the GPL-27T.

So in conclusion
Size - Although the group 31 (from Concorde) appears to just fit, I believe the group 27 should get me through 2 days of boondocking and make installation and service a little easier.

Type and model – Unless I can confirm purchasing the GPL-27T without the automotive posts I was going to buy the solar version PVX-1040T.


Questions:
1) Has anyone installed the newer package Concorde batteries (either group 27 or 31) into the front loading storage compartments like that in my 29’ 1986 Sovereign. Did you have success with the Concorde group 27 with posts?

2) Is there any reason not to use the PVX solar deep cycle version of this battery (vs. the GPL)?

3) Recommended sources for the GPL-27T where you get a good price and can also buy without the post? So far I have found $320 delivered with post ($305 for the PVX).

4) Is there any negatives to using the threaded insert vs the automotive post besides emergency availability? Coming loose? I assume one should use a blue thread lock.

Thanks for any insight as always!
Scott

[ROBERT CROSS]

Do you have a pic of the compartments?
They may be the same as our Classic. If so they have a hinge lip that makes any battery a pain to get in & out.
Our Lifelines were an even bigger problem because of the extra weight.


Bob
🇺🇸

My solution..The strap makes it easier to lift them over and the Lifelines have a strap. The posts just clear.

[uncle_bob]

Hi

Any time you look at putting in batteries, be sure to allow a bit of room for them to swell up. They only do this when there is a problem. You still don't want to confine them to much. The pressure *will* go somewhere .....

Bob

[Harrysheets]

My compartments are similar but from 1986. I can see your aluminum trim is different so the box dimensions could be as well. I also noticed you have the older style of battery case which was re designed this last year.

My compartments also have a step down just past the hinges.

What battery size is in your image?

I'm having difficulty pasting the image here so I added as an attachment.

Scott

[Harrysheets]

Also here is a view from inside the trailer. Scott

[DaveP]

Have you considered just removing the battery boxes, sealing the old battery doors and placing sealed AGM batteries under the couch? This is what I did with my 2004 Classic. You can easily mount four batteries or just two.

[ROBERT CROSS]

Originally Posted by Harrysheets

My compartments are similar but from 1986. I can see your aluminum trim is different so the box dimensions could be as well. I also noticed you have the older style of battery case which was re designed this last year.

My compartments also have a step down just past the hinges.

What battery size is in your image?

I'm having difficulty pasting the image here so I added as an attachment.

Scott

Grp 27s...heavy 🤪, hence the belts.👍

Bob
🇺🇸

[guskmg]

Roger on the swelling. In my infinite wisdom, I had Airstream delete the two AGMs, as I had contracted with the dealer to install my 4 supplied Werker AGMs from Batteries Plus. I did not know the Werker brand was a knock off Chinese rather than a German brand name. After a year or so one of the Werker batteries became defective and swelled up as big as a basketball. Fortunately, it was installed in a marine plastic box. Had it been one that was in one of the Airstream boxes I don't how I could have removed it without making a royal mess. BTW, Batteries Plus would not warrant it because it was a few days out of warranty. I told the clerk to come out and get the swollen battery because I was afraid it might blow up. He grumbled a bit, but came out and got it. I had though Airstream's price was to high for Life Lines. In the end, that was an expensive lesson.
guskmg

[Dan and Liz]

Don’t know bout Concordes, but Trojan Group 27 AGMs fit nicely in our 87 Sovereign.

[Harrysheets]

Dan and Liz - I assume you have the Trojan Reliant "27-AGM" model. If so this is 9.32" high with both automotive and studs. a little lower in AH at 89 but a real contender. Thanks! Its good to know this fits in a similar vintage Sovereign.

Scott

[Harrysheets]

Update:
I took a detour this year and replaced the front belly pan, rebuilt the battery boxes and reengineered the umbilical entry but I'm back to the electrical system.

I decided to build a dummy GPL-31XT to size to confirm it would fit in my stock battery boxes and they just make it with some minor mods. The GPL-27Ts would fit without modifications. The problem with the group 31 is its extra length pushes the automotive type posts farther back into the tapering height of the battery box. The height of the post appears to just hit the top of the box. At the same time the battery length is +0.0 to +0.1 longer than the pocket the battery drops into. This could vary in production as it appeared my ABS boxes could have some variance. I believe I can modify the step at the front of the pocket if my GPL-31XTs are too tight.

In order to give some height headroom I will either purchase the Lifelines without the automotive terminals or purchase the Sun Xtender version which is the same case.

Scott

[Harrysheets]

PS.

Replacement cables - I found replacement cables offered by McMaster Carr which are stainless and fit well.

Umbilical - I reengineered a front mounted umbilical entry that goes through the skin just to the left of the battery box. This uses a die cast box and a standard cable gland from the industrial automation market place. This meets IP67 sealing and allows easy replacement. You can see the box in the photo but not the gland or cable (to be installed in the spring).

Scott

[waninae39]

with lion battery, i could fit upto 10 under the front bed in a 22Fb sport
they can go inside as they do not gas

with lead acid, you must keep them outside

thus Lion is the way to go

BTW, over a 5 year period, they have a lower TCO, Total Cost of Ownership

[uncle_bob]

Hi

Having a hot battery stud bounce into contact with part of the chassis can be pretty exciting. Did it once doing mods as a teenager. Allow lots of clearance ��

Bob

[Harrysheets]

Bob,

The group 24's, 27's, and 31's all have the same terminal height at 9.25" (automotive terminals) so I have the same issue while sliding the battery through the exposed AS shell. Once inside the ABS battery box there is no metal to contact. I had a wrench bridge the + terminal and frame 40 years ago in my first car and that is burned into my memory.

Scott

[uncle_bob]

Hi

I had a friend drop a wrench working on a helicopter. The wrench vaporized when it hit the battery post and frame. They also lost enough of the frame that some serious welding was required to put it back into service. Needless to say, his commanding officer was not amused ...

Bob