How to add charging to manual-start Merc 9.9 4 stroke?

[Gill-T]

I would like to add charging capability to my trolling motor.  Specs are 9.9 Merc 4 stroke manual start.  What do I need?

[Xxx]

I just went through this with a guy a few years ago, part#856558a2'. I think all mercury 9.9 to 15hp 4 strokes can us this cord, the hard part is finding the end, it seems expensive for a extension cord but it had 4 diodes to change from ac. to dc. current. Check out Iboat. Mercury 9.9 four stroke alternator page 1. The local dealer around here didn't even know it exists, after I ordered one he stocked a few also. Hope this helps as I dug for hours and stumbled across this myself. I actually was going to make it but I couldn't figure out how I was going to get a rectifier incorporated in the harness, money well spent.

[DtD]

On a similar note .....and probably only a dream....is there a way to add charging capability to my 1986, 40 elec Yamaha ( Merc Mariner ) ? The engine runs as brand new, but lugging batterires to charge too often is getting to be a little much for this " seasoned " fisherman. And she will not  help with this part of fishing !

[Gill-T]

So I am reading that the 9.9 will only produce 6 amps at full throttle and the small amount of charge happening at trolling speed may not help anything.  What are you seeing PAP on yours?

[Xxx]

I read on the boat forum that the guys were happy with it, I'll have to dig into the amp put out I never looked into that deep.

[Xxx]

Well according to manual, the charging system was designed to replace what the starter used out of the battery, not much, like 6 amp at operating speed, very little at an idle.

[Gill-T]

So it seems that a charging system will not really help with my downrigger power.  What is needed is something between the battery and the riggers that help supply a consistent source of amps.  Does any product out there do this?

[Sk8man]

That fits with my understanding too you have to be really cranking speed-wise to be charging the battery to any significant degree. Idling and slow trolling speeds won't do anything significant to charge the battery.

[Xxx]

I'm thinking a solar panel. LOL.

[weijing3333]

I'm thinking a solar panel,too

[jimski2]

Another deep cycle battery.

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[buckboardjr]

I went to the trouble of fixing my 6 amp charging system on my 7.5 Honda that I troll with and it does charge, but not enough at trolling speeds as it is a very simple diode only, variable voltage system, non voltage regulated.  I always carry an extra deep cycle battery unconnected, as a backup for the starting battery that the down riggers run off from. In the event that they run the starting batt down to low, I can connect the spare deep cycle  and get started. One thing I have noticed with my Fishhawk X4 is that when my starting battery gets low, the fishhawk starts acting up. When I connect the deep cycle standby battery, the fishhawk straightens up. Now when I say the start battery is low, it still has enough in it to crank the 88hp Evenrude but the drop effects the fishhawk. I don't carry batterys to charge them, I run extension cords and carry charger to boat.

[RSF]

I use 6 amp charging system on my main battery from engine. Use a a big deep cycle for the downrigger and electric motor. All day no problems. Between the two batteries I use a Battery Switch which allows for which battery I wish to charge and wish I wish to use. Spin around the lake for 30-45 minutes pretty-much bring the main deep cycle back to full charge.

 

Anyway, both batterys go-on charge once I get home. Or in a pinch, I;ll jump the batterie(s) from the car. All depends how long I'm out and how often I use the big-draw items, mainly the electric 60lb thrust motor. Works for me as I have yet to have a battery problem..oh I do carry a small Min Kota battery charge indicator which willl give me an instant reading of charge condition.

[Xxx]

This year I got to use my boat a few times, what I noticed is I run a 15hp Evinrude long shaft and to push my boat "22ft cuddy" I need to run my motor hard enough that I would think that it would be putting out the full 6. amps. One another note I carry 3 batteries and I run 130amp alt, which I made, at at 1000 rpm it puts out 67amp so when my finder shows 11volts I just fire up the main adjust to 1000rpm and let it run for 45-to an hour and I'm all charged up, we put 7 to 9hrs out on the water and I only needed to do this once a day. I'm happy with my decision, would I go through putting a charging system on a motor used as a kicker "no" used as electric start as a main on a smaller scale boat using or a small boat used on a lake or river not as a kicker or if you use it for multiple reasons.

[meangreencj7]

my dad usees a yamaha 8hp that has a charging ring on it, he only has the 8hp and the downriggers on that battery and it will keep it charged all day long

[RSF]

I use the six amp regulated on my merc 9.9 type M. And yes, four amp output will kick in at about half throttle 3K..and increase from there and max 6 Amp at about 5300 RPM (appx 3/4 throttle).

 

However, I believe CDI made and may still make a 9-10 amp set-up which includes a stator. But I say 6 Amps is better than 0 Amps and as others have said, I too run two batteries. The big deep cycle for the 60lb thrust electric, downrigger and bilge pump. The main for all other light draw stuff. Both batteries have a small trickle charge solarpanel and both batteries are removed and kept charged at home using a 'smart charger'.