Quote Originally Posted by muddymech View Post
i use yellow top very happy with taht, how is the blue top thought about using that once the yellow top gives up the ghost
Sorry mate, I've just seen this.

The Optima blue is good and bad at the same time. It's got additional terminals which have been exceptionally useful for me. I bought this one as I wanted it to be able to start the disco and deepcycle it also as I was trying to run a fridge without a 2nd battery system. I've since gone to dual batteries though as I was alway worried about what I would or wouldn't get in the morning - wrt starting. The problem with the Optima Blue top is that it operates with higher voltages compared to other batteries, and so it needs at least an alternator that is set for AGM type batteries that put out higher voltages than those for wet cell batteries. To keep a long story longer I stuffed an alternator playing in mud and had it rebuilt, but didn't realise the voltage output was down and could never get any good performance out of the Optima. I could even see the battery die half way through a full length single winch! I stuffed that alternator also with a failed and dusty bearing and got a new one that now puts out the proper voltages (between 14.2 - 13.2v) and as far as I'm aware the battery is now charging properly. Just a heads up if you go this way.