Unless you've added a regulator your likely to damage that battery. Those aren't about to stand more than about 14.5 volts. Overcharging is one of the things that voids the warranty. Another is draining below 30%. They're a little touchy.
I got a cheap AGM from Ebay. Works well on my dream and is smaller than the early battery size wise, but with plenty of cranking power. It's an YTX7L http://www.ebay.com/itm/AGM-YTX7L-BS-Ba ... d1&vxp=mtr
It looks like the price has gone down since I got mine.
Battery Size for CA77
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