Anyone use a stereo with the old non-voltage regulated Mercs?

[SeaKaye12]

Hi,<br /><br />I have a 1977 Merc 850 that when running puts out as much as 18 volts to charge the battery.<br /><br />I'd like to hook up a stereo CD player and/or other electronic marine gadgets....and wonder if any of them could tolerate that sort of voltage without burning out.<br /><br />So; your comments about that...and also any suggestions as to what sort of voltage regulators are availabl would be appreciated. I've seen a couple such devices mentioned here. <br /><br />I suppose that some of the radios etc on the market already have voltage regulation protection built in...but I'm not certain.<br /><br />Thanks for reading, Chuck

 

[studlymandingo]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

I would install a rectifier. Apparently the Radio Shack version works well.

 

[Chunder06]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

Why not just use the boats battery.?

 

[tashasdaddy]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

becuase you hook to them same post. thus charging the whole system at 18 volts, frying the equipment.

 

[WillyBWright]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

You can put this in place of that, but you have to do a little wiring and fabricating to mount it. Yellows go to the stator, red to the battery, gray to a tach if needed.<br /><br />I've also seen cheap aftermarket snowmobile rectifier/regulators used. See www dot mfgsupply dot com and enter Voltage Regulator in the Search. That would be one of those "At your own risk" things.

 

[SeaKaye12]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

Chunder06...that would be fine as long as I didn't turn anything on unless the engine was shut off. I have considered trying to remember that...but it would only be a matter of time...<br /><br />Thanks for reading, Chuck

 

[Laddies]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

Willy gave you the only option you have the radio shack deal is a rectifier and won't help a thing

 

[Silvertip]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

There is another option. You can install a Radio Shack 12 volt voltage regulator in the line that feeds the radio. This does nothing to regulate the battery charging voltage but it does regulate the voltage going to the radio. You could install one for a locator as well, or any other sensitive electronics. No - you can't use a low current regulator in the charging circuit. You must use one that can handle the full current output of the charging system.

 

[SeaKaye12]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

Thanks WillyBWright ....the first one (19.99) at mfgsupply looks similiar to what I've seen mentioned here before. <br /><br />The CDI version looks simple enough too...I've already re-wired the entire internal harness...so I'm familiar enough with the present rectifier wiring...as long as I could figure out how the existing wires going to the rectifier would be connected to the new one. I guess I'd have to find room for a junction block to accept the different connections and keep things neat. Anyone got a picture of how they did it? Right now it looks like there are two terminals going to the stator, and two more wires going to the harness plug (12v and tach?). So, I'd need some help to figure out exactly where everything would hook up to the new one.<br />I think I'll look into Upinsmoke's suggestion as well though...although I wouldn't be surprised if the better radios already had a similiar protection already included in their power input wiring. Hard to tell though.<br /><br />Thanks for the replies folks...it's greatly appreciated. I've saved the bookmarks for future reference. <br /><br />Chuck.

 

[Silvertip]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

SeaKaye -- Most electronics have overvoltage protection in them. But that's not the same as voltage regulation. Voltage protection simply cuts off the supply voltage if it rises above a specific threshold. Overall, the best solution is to regulate the alternator output. But small in-line regulators are an option.

 

[Clams Canino]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

Also... if you have a voltmeter on board -you can just watch it. I usually run with bow light and stereo on - no problems at all. It's don't take too much power usage to bring it back down to 13.8 volts or less.<br /><br />-W

 

[SeaKaye12]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

OK Wayne; tomorrow I'll try turning on the lights and watch the meter. Usually, once the engine is running it gradually climbs to 17v and stays there; but I've never really noticed if it drops any when the lights are on.<br /><br />Thanks, Chuck

 

[Chris1956]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

SeaKaye, I have run a stereo in my '77 Merc 1500 inline for 20+ years without an issue of that sorts. My stereo cases rust out and the circuit boards grow green stuff,but I never had one burn out.<br />I always thought the load of the battery should keep the voltage low enough, although I cannot say I ever really checked it. You could buy some number of 14V Zener diodes together in parallel to achieve a 4 A rating or so, install them in a heat sink, and "voila", a primitive voltage regulator (actually a voltage cut out).

 

[phatmanmike]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

about the ones at mfgsupply.com . . . . . . .<br /><br /> if you use this one would you still be able to hook up a tach?

 

[Chunder06]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

What are you using to filter all the noise from the supply, the battery will help BUT I think it will crackly and spit and I still believe you don't require regulation, the battery will take care of that.

 

[Clams Canino]

Re: Anyone use a stereo with the old non-voltage regulated Mercs?

The newer batteries do NOT take care of that. 17v on the system is quite common with only the battery as a load. However, the systen isn't real noisy.<br /><br />-W