Charging Voltage

[mjash]

What should the charging voltage be on a 77 85hp be. I am figuring about 13.5. I am not seeing anything above battery voltage. Replaced rectifier...same thing. RPM gauge does work. Any ideas?

 

[mjash]

Re: Charging Voltage

^

 

[Silvertip]

Re: Charging Voltage

Battery voltage is 12.6 volts. If you are measuring 13.5 its charging. What engine RPM are you measuring at and are you using a known accurate meter that is properly zeroed. One volt of error can make a difference in diagnosis. The 13.5 you measured inidicates its charging, but not knowing the engine speed, it may not charge much. One more volt (14.5 would be very acceptable). Dirty/corroded connections can easily drop one volt.

 

[Basscat 1]

Re: Charging Voltage

Mark, fully charge your battery and clean all the connections to include the red plug at the engine.<br />If that doesnt work you will need to check the stator.<br />My 85hp normally charges at 13.1 or higher, but thats only on the water with the rpms above idle (2000)or higher.

 

[BrianTindall]

Re: Charging Voltage

Your charging system should have about a 9 amp output so don't expect too much. If your tach is not working, it sounds like your stator went south. Check your manual and find the two wires coming from the stator to the rectifier/regulator and measure the AC voltage coming out. You should have about 22 volts AC at these wires. If you do, the check the voltage coming from the rectifier, it should be about 15 to 16 volts DC. If you have a seperate regulator, check the voltage coming from that, it should be about 14 to 14.5 volts DC. A regulator is not needed since the output is only about 9 amps. You can also by diode bridges and regulators from electronics houses that will handle 10 amps. Much cheaper than OEM and work very well. Been there and done that one.

 

[Basscat 1]

Re: Charging Voltage

He says his tach is working fine, so the rectifier is probably ok. <br />I dont think a 77 model 85 hp has a seperate regulator either.

 

[mikemartyo]

Re: Charging Voltage

I have a similar question. I have a 77 85 hp unit as well. at idle in the driveway the voltage off the stator shows 18-19 volts, the red and yellow wire off of the rectifier shows at 14 volts, but i am not getting this voltage down to the battery.

where does the wire go? i am looking on the wiring diagram, it looks clear, but i am not getting charging of the battery.

any suggestions? i do not see a reason why if i am getting power out of the rectifier, i would not get power to the battery..
when i check the battery - it reads about 12.3 v and the rectifier - read from the terminal block positions 7 & 8 gives me 14v.
Mike