70 HP Mariner Outboard: 1982 s/n 6073782 Charging Circuit Problem

[mayberetired]

The original issue was that the battery was not being charged, so prior to fishing trips, I just made sure the battery was fully charged.
After discussion with a local dealer, I replaced the rectifier at his recommendation. After replacing the rectifier, I connected my VOM at the battery and found it to be charging @ 13+ v. at idle. However, when rpm's were increased, the voltage increased to upwards of 17 v. To prevent burning things up, I immediately removed the red wire from the rectifier (insulating it to prevent shorting) to prevent the battery from overcharging.
In trying to find a replacement voltage regulator, I have been told by two different parts sources that this motor does not have a regulator and that the rectifier is the only control this motor has for charging the battery. This, I believe to be in error, as to my knowledge the rectifier's only purpose is in converting AC voltage to DC.
I did locate one source that did provide a part number 12082A 1, but he was not certain it was correct for this OB motor serial number.
I would welcome any thoughts or recommendations toward a remedy to this problem.

 

[carholme]

Re: 70 HP Mariner Outboard: 1982 s/n 6073782 Charging Circuit Problem

See this discussion:

http://forums.iboats.com/showthread.php?t=541288

Here is the parts list for your sn:

http://www.crowleymarine.com/mercury-outboard/675.cfm

Gerry

 

[mayberetired]

Re: 70 HP Mariner Outboard: 1982 s/n 6073782 Charging Circuit Problem

Thanks Gerry. Looks like I really may not have a problem after all. Just the charging circuit replenishing the current used for starting the motor.
Appreciate the help.
Al

 

[Barnacle_Bill]

Re: 70 HP Mariner Outboard: 1982 s/n 6073782 Charging Circuit Problem

You may have damaged your new rectifier by running it without that red wire being hooked up. Be sure to check it. Common reasons for higher voltage is dirty or loose connections or a defective or wrong battery. You must use a marine battery.