Increasing Amp Output??

[ketron47]

I have a 71 Ervinrude, 60hp which has a 9 Amp stator. Is this enough to keep the cranking battery up? or do I need to increase the Amperage output? If so, where can I get the detailed info to do it?

 

[Mark42]

Re: Increasing Amp Output??

9 amps is more than enough to charge the battery, and run a few accessories. If you are having charging problems start by testing the battery and volt output.<br /><br />Other folks here have real indepth knowledge of the elecric sysem on that motor. I just know that 9 amps is plenty of output, if its being put out.

 

[Solittle]

Re: Increasing Amp Output??

I'm not an electrical guy but I don't think you can get more than 9 amps from a 9 amp set-up. Best to make sure you have a good and fully charged battery to start with. As Mark posted 9 amps is plenty to keep a starting battery charged. You may need a second battery if you have a lot of stuff drawing juice in addition to starting.

 

[fireman57]

Re: Increasing Amp Output??

Are you having a problem keeping your battery charged? If you are then there are a couple things to consider:<br />Are you running a lot of things off of one battery like a CD player, trolling motor, GPS, depth finder, etc..<br />Secondly how old is your battery and is it a deep cycle or just a regular small car battery.

 

[ketron47]

Re: Increasing Amp Output??

Thanks for all the inputs. This is my first boat and am in the process of fixing it up. I thought I saw somewhere where you could increase the amperage. I have a new battery for the engine and another deep cyle battery for the trolling motor.<br />Is it feasible or possible to charge both batteries from the engine??????

 

[fireman57]

Re: Increasing Amp Output??

There was a thread on doing this about a month ago. I think the best and cheapest solution is a solar charger. they run about 35.00 and you always have a charged battery.

 

[WillyBWright]

Re: Increasing Amp Output??

There is something called an Isolator that splits the charging current between the batteries but doesn't connect the batteries together. If you're not going to use the trolling motor alot, you might be able to use the trolling motor battery for both tasks If there is a sticker on the trolling motor battery that shows cranking amps, then you can use it for starting or trolling. If you connect both motors up to it, then the outboard keeps the battery charged. If you use the trolling motor alot, then I'd stay with separate batteries and get the isolator.<br /><br />The thing with trolling motor batteries is that they charge slow. Just relying on the motor to charge it is usually insufficient. Most people that use them find they have to charge overnight before the trip. That's where a dual onboard battery charger would be the wisest investment.

 

[dolluper]

Re: Increasing Amp Output??

deep cycle is a must for your motor to keep it operating at peak 9amps is lots,alot of older motors are only running 6amps, you can run two if you hook them up right but I would suggest to hook up a load limiter also with them since it sounds like your running a trolling motor also.Short runs are killers for batterys try throw in some long ones to with the revs above 3000 or planeing

 

[Silvertip]

Re: Increasing Amp Output??

There is no free lunch when dealing with electrical systems. If your engine has a 9Amp alternator, you can't get more than that out of it other than by installing a larger alternator. If your accessories draw more than 9 Amps from the system, your alternator cannot keep up with the demand and your battery will eventually discharge. A deep cycle will not solve this problem, but it can tolerate the prolonged high-current discharge far better than a standard auto battery. Isolators, dual battery setups, and similar arrangements will also not solve the problem. Two batteries require twice as long to charge but they would last roughly twice as long as a single. My suggestion would be to install one marine starting battery for the engine and a deep cycle for your accessories. A dual output charger mounted on-board (6amp each) can be plugged in at the dock. Connect the batteries with a dual battery switch so that under way you can charge either one or both. When fishing, run accessories from the deep cycle. At the dock, set the switch to OFF to disconnect all electrics. Plug in your on-board charger and say goodbye to battery problems. By the way, solar chargers have very low current output and would take forever to charge a battery. They are OK for maintenance purposes during storage.