Defeating the Ridiculous CCA Requirement on Tohatsu TLDI?

RiverSpey

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May 15, 2017
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All I use my battery for is staring my TLDI 50, and sometimes running a low end Garmin fish finder. No trolling motor. No stereo, No lights. It’s a 50/35 set up for running shallow. It came to me with some kind of lawn tractor battery in it and that has worked just fine, but local dealer recommended that I step up to the recommended 800-1000CCA battery. That’s basically going to triple or more the weight of my battery, and at that, put that weight in the worst possible spot in my boat.

So I started reading and hearing about some users getting error messages from messing around with too little battery. I even called Tohatsu, and they told me that I could get error messages- but that other than getting stranded NO harm could come to my electronics from too little battery- but that it would put undue stress on the starter.

So I don’t want to put a 60+ pound battery in my boat, not gonna, which lead me to Odyssey Extreme Series batteries. They give a PHCA rating on their batteries, along with CCA. They claim that PHCA Pulse Craning Amps for 5 Seconds at start is significantly higher than the CCA rating. So, on their PC950, they claim 950 Amps for 5 seconds, then 400 CCA. I’m thinking that even with my way out of spec battery that came with it and has worked fine, it’s never taken more than 5 seconds to turn over, even when really cold out.

So, I guess the bottom line is - is that PHCA rating BS, or is this the perfect battery for me given my limited demands on it? I don’t seem to be the only one on the internet who has struggled with this problem, but I haven’t been able to find anyone who has arrived at the same possible solution.
 

Sea Rider

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If battery is same size don't see an issue using a slight heavier batt with better punch. Are you worried about losing wot rpm, be harder to plane ? can compensate that going for a prop maximization to at least one less prop pitch. Tohatsu OB's factory delivered with a prop are usually medium pitched, probably not suited for your combo to run like the devil's soul. Only possible to check that out with a wot run as loaded and along a tach.

With extreme cold, higher amp batts will work much better when at starts.

Happy Boating
 

Scott Danforth

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could always run longer cables and put the battery in the bow.
 

pvanv

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The TLDI 40/50 is not so tough on the battery, BUT, because the voltage droops when cranking, you need lots of amps to keep above 12v while cranking. I would go with a GOOD group 27 or 31 battery, mounted where the weight has the least impact. If you are always well above freezing temps, you will not need 1000 CCA.
 

bruceb58

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Typically, an AGM battery will have less voltage drop during starting due to the fact they have less internal resistance than a FLA battery.

Putting a battery in the bow of the boat and running longer cables is the exact opposite thing you would want to do. You want cables as short as possible and as large of gauge as possible.
 

Scott Danforth

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Putting a battery in the bow of the boat and running longer cables is the exact opposite thing you would want to do. You want cables as short as possible and as large of gauge as possible.

if you want to move weight to the front, you can move the batteries and up-size the cables. controlling voltage drop is knowing how much to up-size the cables.

I have no problem moving starting batteries anywhere. then again, I also have cables up to 500 MCM at my disposal and can go to 750 MCM if need be. however for the 50, up-sizing to 2 ga should be enough to move the battery to the bow of an 18' boat if the OP needs to distribute weight more.
 

TOHATSU GURU

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You need the bigger battery to energize the ignition system....The starter is a secondary consideration and has no different demand than any other starter for an engine of that size. If you do not have enough CCA's the engine will start and run rough as the coils did not receive enough juice to make them work properly. Tohatsu should have told you that.
 

RiverSpey

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You need the bigger battery to energize the ignition system....The starter is a secondary consideration and has no different demand than any other starter for an engine of that size. If you do not have enough CCA's the engine will start and run rough as the coils did not receive enough juice to make them work properly. Tohatsu should have told you that.

But it starts and purrs like a kitten with far less than recommended. Why would anyone buy a litghetest in class motor, then negate any weight savings by having to put the heaviest battery available in their boat? How do you describe running rough and juicing the coils? I don’t feel like it could run better than it does. It’s not like I have a problem but I often find myself in remote settings where getting stranded would really suck. It is a 50/35 jet and it’s really sensitive to weight. I can tell when I’m running low on fuel because it starts going faster! Adding a monster battery will harm performance.
 

Sea Rider

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Which is the weight difference between a Monster bat and the one in current use ? Can compensate performance loss if that's what bothers you with a prop maximization going 0.5-1 less in pitch and boat forever happily.

Happy Boating
 

bruceb58

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if you want to move weight to the front, you can move the batteries and up-size the cables. controlling voltage drop is knowing how much to up-size the cables.

I agree...as long as you understand how much voltage drop you would have.

Use a voltage drop calculator and you will be surprised how much you need to increase. If the present cables were 4 gauge and 10 feet long with 1V drop at 200A and you moved the batteries just an extra 10 feet which would increase the amount of cable 20 feet, you would need to bump up the cable size to 2/0 to get the exact same voltage drop. And that is just moving them up 10 feet. If you put them in the bow, it would be even worse!

Moving the batteries forward is a losing proposition.

10 feet 4 gauge
http://www.calculator.net/voltage-dr...=200&x=53&y=15

30 feet 2/0 gauge
http://www.calculator.net/voltage-dr...=200&x=56&y=20
 

TOHATSU GURU

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I understand....The CCA requirement is actually around 650 or 700 to work. The reason we tell people to go with a 1000 is that batteries only last 3 years at best and they degrade. So if you started out with the minimum you would probably have issues after only a year.
 

RiverSpey

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Well, this is the AGM battery that’s been running the motor just fine for 3 years in the Pacific Northwest and Montana, often early morning below freezing starts.

//www.batteriesplus.com/replacement/battery/xtreme/xtax20hlbs/cyla20hlbsxta

It is rated at 310 CCA. It weighs 13 pounds. I was looking at going to an Odyssey that weighs 20#, the PC950, also an AGM battery. It’s beefier than what I’ve got now. I might just buy a brand new version of what’s I’ve got. If it’s not broke, don’t fix it right?
 

TOHATSU GURU

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You are asking for trouble. You have been lucky so far. Your luck will not continue. When it leaves you stranded remember that you rolled the dice:)
 

RiverSpey

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You are asking for trouble. You have been lucky so far. Your luck will not continue. When it leaves you stranded remember that you rolled the dice:)

Thanks for you input. I appreciate it. I’m still debating what to do. One question for you, what happens if I’m running my TLDI and I disconnect the battery? Will it continue to run being energized solely from the alternator? If my battery goes bad and I get a jump, will it run to get me home assuming my alternator is good?
 
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