1984 Force 85 HP Voltage out of control

[3scottsbaker]

My engine puts out 14.8 volts at an idle. When I run it at higher RPMs, the voltage ramps up higher until it peaks at around 17.9 - 18.1 volts. All of my marine electronics shut themselves off at 16 volts to protect themselves. What is causing the voltage to do that. What do I need to do to keep the voltage under 16 volts no matter what RPM I am at. Please Help.

 

[eurolarva]

Re: 1984 Force 85 HP Voltage out of control

Hello scott and welcome to iboats. The problem is your motor has a rectifier but does not regulate the voltage. How new is your battery and what size it it. A new fresh battery may help bring the voltage down. Another try could be using a different rectifier. Merc part number is FK650450 and cost about 33 bucks. Newer model force motors have regulators. You might consider getting a cranking battery for the motor and put the rest of your electronics on a different battery. Cranking battery would only be around 40 to 50 bucks. It might be possible to incoporate a regulator to your motor but that could cause other problems.

 

[RRitt]

Re: 1984 Force 85 HP Voltage out of control

i think something is wrong with your battery circuit. You should not be able to get 18V at your electronics if your battery and connections are healthy. The battery can suck down more juice than the engine can generate. Something is keeping that electrical juice from flowing through the copper and into the battery. it's just like water in pipes. you probably got a clog (corroded connection), a broken pipe (loose wire), or the battery is broke. my first guess would be a stern mounted battery that has both engine and cockpit feeds screwed down to the same corroded terminal post. the two wires connect well with each other but not so well to the battery.

 

[roscoe]

Re: 1984 Force 85 HP Voltage out of control

Sure sounds like battery or connections to me too.<br /><br />You battery is an integral part of the voltage regulating system.<br />A bad cell, bad post, bad connection, and the voltage has nowhere to go.<br /><br />Try a different battery, let us know.

 

[3scottsbaker]

Re: 1984 Force 85 HP Voltage out of control

Thank you all - I checked and cleaned all of the connections - And I purchased and installed the new voltage rectifier - The battery is only about a 1 1/2 years old - I will take the boat out this weekend and test it out.

 

[roscoe]

Re: 1984 Force 85 HP Voltage out of control

Still think it is the battery.<br />You would not believe how many batteries go bad, or are bad when they are new.