mercury 115 charging two much

[kiranta]

My merc 115 is charging up to 16 volts and I can't seem stop it, have new battery fully charged replaced rectifier and cleaned all the connections I could find, and disconnected tack lead but still charging. Is this to much for the battery.

 

[graddy]

Re: mercury 115 charging two much

How and at what RPM's are you testing this?

 

[Gold Bear]

Re: mercury 115 charging two much

motormec <br /><br />What year is your engine?<br /><br />My 1972 model 115 Mercury puts out 17 volts at full speed.<br /><br />Your engine probably has an unregulated charging system (like mine). Mercury recommends in their service manual that you use a starting battery (versus a deep-cycle battery) with caps over the cells so you can monitor the electrolyte level.<br /><br />I have never had any problems with this set up. I don't think it hurts the battery.<br /><br />Good luck,<br /><br />Gold Bear

 

[kiranta]

Re: mercury 115 charging two much

Thanks DTS and Gold Bear It's a 1988 and I was thinking they charged quite a bit without a reg. When you get over the hill you can't rember everything. Happy motoring

 

[Jerry M.]

Re: mercury 115 charging two much

Goldbear...My 1992 Merc 50 charges at almost 16V and I thought it was a major problem til I read your post. It has a regulator which I thought might have been bad since the manual sez it should be 14.5V. A new reg cost $140 so I hesitate replacing it. The other concern is the rectifier, it burnt out and I assumed it may be because of the excessive charging voltage. My battery holds about 13V after a day of boating so it doeasn't seem to hurt the battery. <br /><br />Have you had any problems with your rectifier?<br /><br />Jerry

 

[mellowyellow]

Re: mercury 115 charging two much

GEEZE! my new rectifier cost $35, but they nicked<br />me an extra $7 for a mount plate for the new style. ('70 1150)<br />and I was miffed about $7 for a POS bracket.<br /><br />anyways, a simple inline lightbulb may draw enough<br />juice to get back to reccomended voltage.<br />good luck,<br />M.Y.

 

[Jerry M.]

Re: mercury 115 charging two much

Mellow, My rectifier was $40 x 2 since two blew out in a month, and the regulator will be another $140 if I replace it. I might try your bulb idea

 

[AndyL]

Re: mercury 115 charging two much

If you thought that was expensive try buying one in the UK. A voltage regulator is £165 +17.5% tax.. That is $310 or a million dog dollars.<br />Plus fitting!!!<br /><br />It hurt when I found out one of mine had gone down only after fitting a voltage sensitive Furuno echo sounder. It had probably been down for ages but all my other stuff works over a larger voltage range.<br /><br />Deep depression at the start of the boating season.<br />Andy

 

[Gold Bear]

Re: mercury 115 charging two much

Gone fishing <br /> <br />My 1972 inline 115 has a "battery operated ignition" and an un-regulated charging system - so there is no regulator, just a rectifier. At the dashboard I have a volt meter that lets me know the charging system is working. If the rectifier fails, I know that I can only run the engine about an hour before the engine's ignition will quit!! (Don't worry about me though, I have a deep cycle battery and a master switch, so I can switch over to that in order to get back home.)<br /><br />To answer your question, no I haven't had any problem with the rectifier. When I first bought the engine (about 18 months ago) the stator had some bad wiring, so I replaced it. Otherwise the charging system works just fine.<br /><br />Best regards,<br /><br />Gold Bear

 

[Jerry M.]

Re: mercury 115 charging two much

Andy...may be expensive but you get "free" health care. I feel for you.

 

[Yepblaze]

Re: mercury 115 charging two much

Run with the running lights on. Just remember to turn them off when you get there.