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Re: New batteries [message #183147 is a reply to message #183112] Wed, 05 September 2012 05:47 Go to previous messageGo to previous message
mike miller   United States
Messages: 3576
Registered: February 2004
Location: Hillsboro, Oregon
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Senior Member
thorndike wrote on Tue, 04 September 2012 16:49

Well, I am back again. After family issues detoured our RV maintenance, I am working on getting it back up and running.

I went out to the lot today and discovered that my batteries are dead. They are not new batteries, so I am going to replace them. The question is, does anyone have recommendations for replacement batteries?

Bob
----
Robert Peesel 1976 Royale 26' Side Dry Bath Sterling, Va


Bob,

I agree with the others here about a pair of 6v golf cart batteries for the house 12v bank. But it might not be as easy as it could be... I notice that you have a Royale.

IIRC: Most Royales came with three 12v batteries. One Engine starting battery with a "house" battery next to it up front. They also had a full sized 12v battery in the rear next to the Onan. This is alright for battery longevity so far, but some bright person at Coachman figured why not use the extra capacity of the rear battery and paralleled it through a long cable with the house battery in the front. (Look and see if your system is still this way.)

This system "works" but sets up a situation where the house batteries draw down each other. This is very hard on batteries making them only last a few years. Even "matched" batteries with a long cable between then will "eat" each other and not allow the capacity of both batteries to be full utilized.

I recommend removing the 12 volt house batteries and replacing them with a pair of 6v golf cart batteries... but mounting them next to each other. Either up front or in the back, where is up to you and your use for the coach.

Up front gives you more storage in back, more weight on the front axles. In the rear puts the weight in the back, keeps the front area less cluttered, but will cost a bit more to keep the "boost" system usable.

If you put them in the rear, I would use the wiring diagram for the later GM upfitted coaches, as a guide. If you mount them up front, the last Birchavens have a good set up to copy. (With either you put the two 6v batteries in series in place of the single 12v house battery shown on the diagram.)

Both methods will, most likely, require a new battery tray. Plus, if you do not already have them, I would also add a modern converter (with smart charge capability) and a combiner. Someone else has mentioned a solar panel to maintain the batteries while in storage. (I keep mine plugged in.)

Due to the increased longevity of the batteries, the swap should pay for itself in a few years. The increased house battery capacity is a bonus.

Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com

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