electric charging for a 2003 15 hp 4 stroke yamaha manual start -tiller steered outboard

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lenten

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want to add electric charging to above outboard----any recommendations for suitable engineers---preferably lower non tidal thames but could be further after lockdown---------thanks
 
I suspect that upgrading an old engine will not be an economic proposition and it may be better to sell it and buy another one with charging capability. It will be interesting to hear how you get on with it?
 
lenten said:
want to add electric charging to above outboard----any recommendations for suitable engineers---preferably lower non tidal thames but could be further after lockdown---------thanks
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The Yamaha rectifier is over $100 in the USA, but you sould be able to find a suitable bridge rectifier for under a fiver from an electronics component supplier.

However ITYWF that the necessary coil assembly is NLA.

A secondhand coil and a bridge rectifier is the way to go if you want to try this DIY
 
First make sure you do not have a lighting coil under the flywheel. (In addition to ignition coil) If you don't have a coil then look for a S/h one but I would not rate your chances unless you can find a motor dismantler. (wrecker) (go for solar charger)
If you have a coil then it is easy to fabricate a bridge rectifier. You will ned an amp meter to determine just how effective the sytem is at charging the battery. Often quite ineffective as they often were made to run lights ie not good at providing 14v to charge a battery. Bridge rectidiers are avaible quite cheaply, However you will do a lot better making one up from 4x schotky diodes which have a much lower volt drop loss. bridge rectifier wiring - Google Search might give you some ideas. As you will see the current goes through 2 diodes at any one time (positive cycle through 2 negative cycle through the other 2 so the volt drop of a silicon diode is multiplied by 2 so you lose 1.4 volts Schotky ddiodes at about .25 volt maen only .5 volt lost
These kind 2pcs ESAC82-004 10A 40V Schotky Barrier Rectifier C82-004 TO220 FUJI | eBay have 2 diodes in the one package. Bolt them down to ali plate for heat dissipation. But isulate the palte or the didoed from the plate. Might not be needed. However you will need 3 of these as the orientation of one pair is OK for one side of the bridge but all wrong for the other side so you use 2 halves. good luck ol'will
 
William_H said:
First make sure you do not have a lighting coil under the flywheel. (In addition to ignition coil) If you don't have a coil then look for a S/h one but I would not rate your chances unless you can find a motor dismantler. (wrecker) (go for solar charger)
If you have a coil then it is easy to fabricate a bridge rectifier. You will ned an amp meter to determine just how effective the sytem is at charging the battery. Often quite ineffective as they often were made to run lights ie not good at providing 14v to charge a battery. Bridge rectidiers are avaible quite cheaply, However you will do a lot better making one up from 4x schotky diodes which have a much lower volt drop loss. bridge rectifier wiring - Google Search might give you some ideas. As you will see the current goes through 2 diodes at any one time (positive cycle through 2 negative cycle through the other 2 so the volt drop of a silicon diode is multiplied by 2 so you lose 1.4 volts Schotky ddiodes at about .25 volt maen only .5 volt lost
These kind 2pcs ESAC82-004 10A 40V Schotky Barrier Rectifier C82-004 TO220 FUJI | eBay have 2 diodes in the one package. Bolt them down to ali plate for heat dissipation. But isulate the palte or the didoed from the plate. Might not be needed. However you will need 3 of these as the orientation of one pair is OK for one side of the bridge but all wrong for the other side so you use 2 halves. good luck ol'will
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Good point. It may well already be fitted.

Id not mess about making a rectifier when its so easy and cheap to buy a suitable one from RS or Rapid. Volts drop is not likely to be a problem. The need for a regulator is more likely
 
thanks for all replies------unfortunately i wouldn t recognise a coil---a rectifier or a regulator if i saw one----i need one professionly fitted----i have got a 15 foot open boat which i mostly use for short trips on the river and sea but occaisionlly longer sea trips----round the isle of wight 12 hours-----eigg -muck-soay-skye 10 days camping------i like to keep the engine in A1 condition----i have been towed in by the rnli once---never want to bother them again

























































































































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VicS said:
Good point. It may well already be fitted.

Id not mess about making a rectifier when its so easy and cheap to buy a suitable one from RS or Rapid. Volts drop is not likely to be a problem. The need for a regulator is more likely
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Hi Vic I must say my experience was with my very old Johnson 6 which had a lighting coil. I found I got a lot more current into a battery with the schotky diodes. It seems to have 2 coils in series and possibly out of phase AC from them. I got best current from using them in series. About 1/3 amp if I recall. I gave up on the charging but then on the engine itself anyway. I get away without an engine. Anyway what is clear is that you need an amp meter to confirm actual results.
As for OP wanting to get professional help I would say go for solar and a bigger battery. I think pros will charge a fortune and probably fail to deliver. ol'will
 
William_H said:
Hi Vic I must say my experience was with my very old Johnson 6 which had a lighting coil. I found I got a lot more current into a battery with the schotky diodes. It seems to have 2 coils in series and possibly out of phase AC from them. I got best current from using them in series. About 1/3 amp if I recall. I gave up on the charging but then on the engine itself anyway. I get away without an engine. Anyway what is clear is that you need an amp meter to confirm actual results.
As for OP wanting to get professional help I would say go for solar and a bigger battery. I think pros will charge a fortune and probably fail to deliver. ol'will
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IIRC the same as my Evinrude.......... which needs a 6 diode rectifier.. Pretty sure I sent you some info donkeys' years ago. Interesting that you got best results with them in series

Pretty useless for changing the battery on a small sailing boat .... normally the engine is not running for long enough.
It's still all connected up but in practice all the charging is done now by a small solar panel

I dont know what the output of the lighting coil and rectifier is in the Yamaha in question but more recent / current models appear to have a 10 amp stator coil and a combined rectifier / regulator
 
thanks aquaboy----aquaboy sent me a link to video where the mechanic is showing how to fit electric charging to a 20 hp yamaha----he says if its got a coil yamaha use 1 green wire and 1 green and white wire-----yes i have got those----then i find what looks like a regulator/rectifier hidden away----so thanks for all replies---i might have been wasting your time-------it now looks like i might just need some wireing to connect to the battery???-----before i posted on here i asked a marine engineering firm for a quote ----i had used them a couple of times to sonic clean my carb and they claim to specialise in honda and yamaha-----i gave them all the serial numbers ect. but they never got back to me-----i have now lost confidence in them so i am looking for a firm that specialises in marine electricals
 
There are quite a few videos out there by Dangar Marine

Those I have looked at seem pretty good
 
have seen a few of his videos and he seems like he knows his stuff including electrics------ seems to me a lot of good mechanics aren t so clever on electrics-----present company excluded
 
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