Over voltage

[SteveA]

I've a Yamaha 5hp 2 stroke from which I charge the battery - having recently installed a fixed VHF, when running yesterday, the radio starting giving an over voltage alarm. When I checked it was over 16v. i guess this means that the outboards charging circuit is unregulated. What and where do I put something to stop this.
Your guidance will be much appreciated.

 

[oldsaltoz]

As temporary fix you could try putting a meter across the battery, increase revs under a light load and limit the RPM to 14 volts till you find a long term fix.

 

[lw395]

A series regulator from a motorbike will do the trick, they are usually combined with a rectifier and cost over 50 quid. Electrex make aftermarket ones as some originals e.g. Ducati can be unreliable, although mine is fine!
If the max current of the outboard is not too high, a shunt regulator intended for a solar system might work, but these work by dissipating the excess power, so must be adequately rated, and get hot etc.
You could get a voltmeter and just switch the charging off when the volts rise.
Have now found website:http://www.electrexworld.co.uk/rg12...ts-for-motorcycles-electrex-world-1331-0.html
£25. If your lighting coil is not over 100W. I think this is a shunt reg, suggest ask them
HTH!

 

[boatmike]

It actualy means the outboards regulator in boogered.... Fit a new one!!

 

[NorthUp]

Try a bigger battery capacity- get a cheap ford fiesta or similar sized one, and it will 'sink' the excess voltage

 

[William_H]

My first reaction was that the battery terminal has gone corroded or fallen off. I wouldn't have thought a small o/b generator could have overcharged the battery. (maybe a small one)
You need to check the actual battery voltage measure on the lead post of the battery with engine running. On the other hand the battery may be cream crackered. This especially so for small SLA types.
If it is battery overcharging then just disconnect the engine charger if you are doing a long engine run.Or get a bigger battery. olewill

 

[JustMelfort]

Ebay "Voltage Regulator 12v" £15

 

[SteveA]

Many thanks for all the suggestions - the battery is OK I have a small solar panel that keeps it topped up and all connections are sound. It looks like it's going to be ebay then