Yamaha 8 hp kicker charging main battery

[RiverBoy]

I finally got around to doing some much needed wiring maintenance on my boat. Fixed all the nav lights, horn, etc. Anyway, I run a 2003 Yamaha 8hp F8MSHC as my kicker. It is not connected to my battery at all, and I fish all the time keeping my gps on, and dragging cannons from 200+ feet of water.
Obviously, this makes me nervous.
I could be wrong, but I don't believe this motor has the capability to charge a battery. Boatland in Campbell River says they can install a rectifier ( I think ). Anyone had this done? And what is the associated cost?

 

[gungadin]

If yours is an electric start model you already have the regulator/rectifier installed, it is just not hooked up.
here is a link to your engine parts list. It appears that you may have a 2004 as well

http://www.boats.net/parts/search/Yamaha/Outboard/2004/F8MSHC/parts.html

 

[RiverBoy]

Oops. Mine is a pull start. It is a 2003 4 stroke. Thanks for the info gungadin. So is it not possible with my motor?

 

[Charlie415]

Still possible just need more parts. Check with your Yami dealer.

 

[gungadin]

Yes it is, under the cowl, there is a rotor assembly (it's what turns when you pull the starter cord) and under that there is a lighting coil, that provides alternating current for a small light bulb. You need to rectify that current to direct current, with either a simple rectifier or a regulator/rectifier. The rectifier will change the alternating current into direct current and the voltage regulator will keep the voltage to about 14 volts. This comes at a price however-- heat, so much so that some outboard manufactures cool the assembly with the water in the engine. Using just a rectifier is a simple hookup, but it uses the battery as a regulator. The voltage will rise as high as 17 volts if you run the engine at high rpms for a long time. Using it as a kicker would minimize this voltage rise. Look under your cowl and you should see two wires of the same colour coming out from under the rotor assembly. I think they are green, but in any case they they go nowhere and are usually capped with a soft rubber see through connector. If you can find these you are good to go and all you need is a rectifier or a rectifier/regulator. The maximum output is only about 7amps but it will be enough to give you a little piece of mind.

 

[RiverBoy]

Yes it is, under the cowl, there is a rotor assembly (it's what turns when you pull the starter cord) and under that there is a lighting coil, that provides alternating current for a small light bulb. You need to rectify that current to direct current, with either a simple rectifier or a regulator/rectifier. The rectifier will change the alternating current into direct current and the voltage regulator will keep the voltage to about 14 volts. This comes at a price however-- heat, so much so that some outboard manufactures cool the assembly with the water in the engine. Using just a rectifier is a simple hookup, but it uses the battery as a regulator. The voltage will rise as high as 17 volts if you run the engine at high rpms for a long time. Using it as a kicker would minimize this voltage rise. Look under your cowl and you should see two wires of the same colour coming out from under the rotor assembly. I think they are green, but in any case they they go nowhere and are usually capped with a soft rubber see through connector. If you can find these you are good to go and all you need is a rectifier or a rectifier/regulator. The maximum output is only about 7amps but it will be enough to give you a little piece of mind.

I'm always amazed with the wealth of info on sfbc. Thx gungadin

 

[RiverBoy]

So, Yamaha has an optional rectifier kit . ( part # 6G1-81970-00-) According to Yamaha, " installation of this will allow for a "6 amp unregulated charge to the battery." If I'm trolling, for, say an entire morning, will that be enough to keep my battery topped up? I'm outta Campbell River , which means I submarine fish all the time. Anyone have an idea how much draw on the battery dragging twin 12lb cannons from over 200 +'feet ?

 

[Fish Assassin]

I have a T8 that comes with the rectifier. My boat has a single battery, electric riggers, GPS, radio, iphone plugged in , dragging two 15's over 200' at Kitty and I never have a problem. My T8 actually charges my battery better then my 90hp 2stroke.

 

[RiverBoy]

I have a T8 that comes with the rectifier. My boat has a single battery, electric riggers, GPS, radio, iphone plugged in , dragging two 15's over 200' at Kitty and I never have a problem. My T8 actually charges my battery better then my 90hp 2stroke.

Exact scenario.,well....., that makes me feel more confident about installing the rectifier. Thanks

 

[gungadin]

The rectifier is fairly easy to install. There are two green wires that just plug into the ones on your engine, does not matter what to what. The red wire goes directly to your battery positive terminal (+). The black wire is your ground, remove an accessible bolt that is on your engine proper,(block) clean the paint off around the area the bolt came out of. Run the black wire to it and run another wire from under the same bolt to your battery negative terminal (-). Use some dielectric grease on all the connections. Use crimp style heat shrink connectors. There should be someplace at the front of the engine that you can push the wires (16ga) through to get to the battery--leave enough slack so that the wire won't get tight when turning or tilting. Do NOT run the engine with the rectifier hooked up without having it connected to the battery, you will fry it in an instant. If you need to run the engine out of the boat or not connected to the battery, just disconnect the rectifier at both the green wires. If you are using wing nuts to secure the connections at the battery, replace then with stainless lock nuts and use flat washers underneath them. The size is probably 1/4 and 5/16. Daigle or Cdn Tyre have them.

 

[RiverBoy]

The rectifier is fairly easy to install. There are two green wires that just plug into the ones on your engine, does not matter what to what. The red wire goes directly to your battery positive terminal (+). The black wire is your ground, remove an accessible bolt that is on your engine proper,(block) clean the paint off around the area the bolt came out of. Run the black wire to it and run another wire from under the same bolt to your battery negative terminal (-). Use some dielectric grease on all the connections. Use crimp style heat shrink connectors. There should be someplace at the front of the engine that you can push the wires (16ga) through to get to the battery--leave enough slack so that the wire won't get tight when turning or tilting. Do NOT run the engine with the rectifier hooked up without having it connected to the battery, you will fry it in an instant. If you need to run the engine out of the boat or not connected to the battery, just disconnect the rectifier at both the green wires. If you are using wing nuts to secure the connections at the battery, replace then with stainless lock nuts and use flat washers underneath them. The size is probably 1/4 and 5/16. Daigle or Cdn Tyre have them.

Thanks again gungadin

 

[Rockfish]

I have said this before, If you have the room and buoyancy reserve and want some piece of mind, Swap out your single battery for a new one after 2 or three years while the old one still tests well and then use it for ballast somewhere on the boat. I keep it charged up and use this battery to offset the weight of the kicker which is on a far outside corner. Keep the old battery completely unconnected but carry jumper cables. That way you know you always have a good fully charged battery if something happens to your main/s. In my case I have a duel battery setup so this is my third battery.

If you fish for enough years you are going to run into someone who has a dead battery and you can start them off your disconnected battery and not risk a dirty power surge from their old motor when it starts up frying the expensive electronics on your motors. Added big bonus if you can get them started is that you won’t have to tow them in.

 

[Bag-Juan]

I installed a rectifier on my 2007 - Yam - 8hp 4-stroke when i got it in 2010, got it at SnG, i think it was 45$ for the rectifier and then they wanted 65$ for the wire harness that plugged into the rectifier and went to the battery. I bought the rectifier and made my own harness as it was just a piece of two wire 12gage i think with a couple of butt conectors on one end that plugged into the rectifier and the round rings on the other end that run to the battery, cost about 5$ probably ,i had the stuff here allready so did not have to buy anything for the harness. The Yami had the plugs there to plug in the rectifier and a spot right there predrilled and tapped to mount the rectifier, - works great. I think when i bought the rectifier there was a choice of a 3 amp or a 6 amp or something like that i went for the higher output one. Good piece of mind while you are out there for sure. Also good to have the battery voltage display on your fishfinder, and set the the alarm to go off if the voltage dips below 11.4 i believe that is what i have mine set to. Dual battery's on a switch is never a bad idea either. I got lots of harness wire if anyone needs a piece let me know, PM me.

 

[cannibal chris]

I have an 06 Yamaha 8hp high thrust and want to tie that into the battery system. I took a pic of the red and green wires and is that what I run to the battery? Thanks.

 

[gungadin]

I have an 06 Yamaha 8hp high thrust and want to tie that into the battery system. I took a pic of the red and green wires and is that what I run to the battery? Thanks. View attachment 9487

The ones I have looked at did not have the two green wires in one connector, they were separate. Follow the and see if they go under the the rotor assembly.

 

[cannibal chris]

It looks like one of the one of the green wires goes in behind where the starter would be. Is that the rectifier?

 

[Rum Buddies]

I'm confused - so is a normal electric start kicker already setup with a build in rectifier? I'm assuming it must since you have to connect to your battery for it to start?

 

[SpringVelocity]

The rectifier might be an option...But yours might have one already.

I have my T8 set up with a removable plug to the motor connected to main battery. When I put motor on boat just plugs right in....I just got ACR dual battery system now work very good if your concerned about charging etc/switches. Does everything automatically....

The kicker hardly charges as low RPM while you troll so you know..... I would go for another battery personally if you really worried about draining power...

 

[cannibal chris]

so I am getting my rectifier on Friday and was wondering what I am suppose to do with my red wire? I have 2 green wires that are combined and another loose red one. I don't have 2 separate green wires to hook up to? its an 06 Yamaha h8. any help would be great. there is a pic of the wires in post #14