Location: Green Bay, WI | Shep - 5/2/2012 12:39 PM
Tom,
MCA is the appropriate rating to apply. CA is the same, rated at 32 d F.
CCA is about 20-25% less than MCA. Rated at 0d F.
I know my Opti's all required 1000 MCA. 135HP to 200HP. Can't say about the 115. Should be in the manual. Or ask your dealer.
Point is, the Maxx 29DC has 875MCA, and only 675 CCA. Would not meet requirement for my motors.
Snip...
Ah... The Stealth guy did say that I should go with something in excess of 800 CCA, so that would be about 1000 MCA using your information. But he called-out those Walmart batteries by name though, so I am not sure if there are different models with different ratings?
Good to hear you have had such good luck with your Optimax engines! For the record, I didn't choose the 115 Opti on this boat. It was a 2009 boat that never sold, and originally came with a 115 Optimax. I would have preferred a 115hp 4-stroke, truth be told--but that's only because I am much more familiar with the technology than with the direct-injection 2-strokes. But the sales price was just too good to pass up, so I talked to a few guys who know the technology. Steve Worrall told me the 115 Opti is a great engine, and now you're the second to report that--so I don't think I'll have any problems. But as the 4-stroke is only about 25-30 pounds heavier in the 115hp size, I probably would have gone that route if I had a choice. But if I do much trolling with this boat, I'll undoubtedly add a Pro-Kicker as it didn't come with one. That's one of the reasons I am so interested in this battery thread, by the way.
Because I am interested in installing something like the Stealth on-board (AC/DC) charging systems, I need to consider how many batteries I will be trying to charge with the engine alternator. If I went with a large marine battery for the engine start and electronics system, then the Stealth unit would work great--it would handle the start/electronics battery, as well as both trolling motor batteries in my 24-volt system. The 115 Optimax has a 60-amp alternator (the 4-stroke 115 only has a 50-amp, btw), so I think this would probably give me plenty of extra charging current for all three batteries. But if I went with a FOURTH battery to separate the start and electronics circuitry, then I am not 100% sure the Stealth charger will work as well. The tech support guy thought it would be OK, but he recommended that I try it with just three batteries to start.
Incidentally, if I decide to troll a lot and do buy a Pro-Kicker, I will likely buy the 15hp unit. It's about $300 or so more than the 9.9hp, but it has a 12-amp alternator where the 9.9 has only a 6-amp alternator. If you've ever tried to troll in the wind in Lund Tyee with a canvas top-set deployed (my 1750 Fisherman is basically a small Tyee), then you know that you cannot have too much power. The 9.9hp Pro-Kicker I had on my 1850 Tyee was just not enough engine to control the boat in strong winds. So I think I'd go to the 15hp unit this time--especially given the increased alternator output.
Great thread though...lots of useful information!
TB |
