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Battery compartment weight limit

February 18, 2017, 03:42:03 pm

I currently have 4 - 6V T145 batteries in my battery compartment (U320).
When I acquired the coach it had 2 - 8D batteries.

I now want to increase battery capacity with 4 L16 battery's, this should add considerable weight to the compartment floor.
How much weight will this floor support?
Any tips on strengthening the floor area?

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Re: Battery compartment weight limit

Reply #1 – February 19, 2017, 12:01:50 am

The floor structure is welded steel tubing with a fiberglass sheet on either side.  How much will it hold?  Good question. Mine has two 8Ds sitting in a frame on the floor and another in a frame above those.  That is about 480 lbs.  Make sure the frame for your new batteries mounts where the old frame did and make the area of the feet much bigger.  You probably should maintain the air space under the batteries so some stout feet are needed.  You can find the steel framing with a strong rare earth type magnet.

That section of floor is probably pretty robust with the batteries, the fuel tank and the LP tank up there.  Make sure your front bulkhead looks secure.

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Reply #2 – February 19, 2017, 12:27:59 am

Interesting question...  We are all concerned about bulkhead Rolock bolts holding, but it seems to me that ALL the thousands of pounds we carry on bay floors should have also caused us problems, but we seldom hear of any.  The floor is just Rolock bolted up into bay wall bottoms, and the bay wall is just Rolock bolted to the interior floor.  How does all this work so well...  Just seems that the bay floor should carry whatever we put on it.  I did learn that to keep the bay walls from leaning forward or backward, there is usually a short front-to-back wall section that also separates adjoined compartments, so it is important to not remove this wall section when remodeling.

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Reply #3 – February 19, 2017, 12:44:39 am

I rebuilt my front and rear bulkheads ( I cut away 8" across the belly of the coach to inspect and clean and paint.) by drilling and cross bolting with 3/8" grade 8 - zinc coated bolts. My coach had a double 1 1/2" beam up front. I feel confident that the bulk heads are secured.
That area has a lot of weight. The batteries are next to the fuel tank and the large propane tank is across from that. A bit further back on the same side as the batteries is the 300# residential refrigerator. Lots of weight goes into the 2 bays that separate the areas.
I hope a couple hundred more pounds won't break the camels back.

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Reply #4 – February 19, 2017, 01:21:17 am

I would think think you should be good to go.  I have an Aqua Hot in there as well but there is an extra pair of NS bulkheads between the full width bulkhead between the AH and the fuel tank and at the back side of the battery area and then out to either side. 

Post a picture of your mounting frame when you have it.  I am doing the same thing on the other side.  There is room for six L16s on either side. 2400 amp hrs!

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Reply #5 – February 19, 2017, 02:32:02 pm

Without major re-configuration of the battery compartment I will need to lay the L-16 batteries on there sides to get under the height restriction of the bay. My batteries are under a shelf that supports my inverter, 12v air compressor, air system computer.

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Reply #6 – February 19, 2017, 03:11:23 pm

Can you do that with AGM batteries?  Probably but I would ask.

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Reply #7 – February 19, 2017, 09:06:13 pm

Without know anything about your batteries, it sounds like a long term problematic choice to lay battery on side.  Sounds like it is time to find a different battery size.

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Reply #8 – February 19, 2017, 11:48:41 pm

Or maybe moving some equipment a bit.  I would be concerned putting the batteries on their sides.

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Reply #9 – February 20, 2017, 02:33:47 am

I will check with manufactures but all the data shows that an  AGM  can be mounted any way but upside down.

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Reply #10 – February 20, 2017, 08:29:17 am

I just put 6 L16's in mine.  Had to weld a new frame - the new frame had 6 feet instead of 4, and made sure that they sat on the two metal bars that pass through rather than insulation-backed fiberglass.  But they feel very solid - pass the eye test with flying colors.  My primary concern was axle weight and left-to-right weight distribution from the extra 400-500 pounds.  Right or wrong, I was not very concerned with the compartment itself given the framing strength I can see elsewhere.

Drove 800 miles right afterwards - compartment still looks great. If the battery compartment starts dragging/sagging in the next few months (or some other similar event)  I'll be sure to pass that information along!

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Re: Battery compartment weight limit

Reply #11 – February 20, 2017, 08:30:54 am

From the Trojan Battery User Manual:

3.9 Battery Orientation
Deep-cycle flooded/wet batteries must be placed upright at all times. Fluid in the battery will spill if the
battery is placed on its side or at an angle. Deep-cycle AGM or gel batteries are non-spillable and can be
placed either upright or on their side.

Jim - awesome installation - every Foretravel owner's dream...
With those Crown batteries what are your total Ahs?
Time for an alternator upgrade...?

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