my evinrude not charging battery...help

[thuber]

I have an 1988 88 special 88hp evinrude outboard. The system is an unregulated system, which I also want to convert. The battery is not charging. Here is what I checked. The rectifier has been replaced. I measured 21 volt AC off the stator with motor running, wires not connected to rectifier. I measured 42 volts DC off the rectifier red lead and ground (rectifier not connected to rest of electrical system). With motor not running, the resistance on the stator wires is 1.5-1.6 ohms. Both leads are open to ground. When everything is connected, voltage across battery is 12.34 (the fuse between battery and rectifier is good)and only changes .1 volt with RPM's increased. Battery is new. My thought is the stator is breaking down under load. Is there anyway to check stator under load and is there anything else I can do short of buying new stator an installing to see if that fixes problem. I don't mind buying one, but I don't want to replace it if that is not what is not the problem.

 

[bktheking]

Re: my evinrude not charging battery...help

You are checking the voltages with a meter? At the same time did you physically test the new rectifier with a a diode check with the meter? It's not unheard of to get a bad part.

 

[ezeke]

Re: my evinrude not charging battery...help

You check the ungegulated rectifier with an ohmmeter. It's a system of blocking diodes. Here's the drill: http://forums.iboats.com/showthread.php?t=190638

The stator tests are found here: http://cdielectronics.com/InstallSheet/173-3536.pdf

Information on charging/battery problems here: http://cdielectronics.com/downloads...ues, Regulator-Rectifiers and Tachometers.pdf

Quiz at 5:00 today.

 

[Vic.S]

Re: my evinrude not charging battery...help

The 42 volts output from the rectifier is rather unexpected!

With everything connected (but not running) check that you have battery volts at the red lead on the terminal strip. If not investigate for bad connection between there and battery.

when running check the DC volts at the terminal strip. Should of course be the same as you get at the battery terminals

Good idea to use an old fashioned low impedance analog meter rather than a very high impedance digital one. Better still use a bulb on a couple of wires to check the DC.

 

[thuber]

Re: my evinrude not charging battery...help

The voltage off the stator coil is 21 volts AC. The voltage out of the rectifier is 42 DC. Doesn't that mean the rectifier is working.(low amps) I will do the rectifier check again (checking the resistance) I will also check the stator coil using the info. provided. That's for responding.

 

[F_R]

Re: my evinrude not charging battery...help

In the first place you shouldn't be running it with the rectifier disconnected. Notice you got 42 volts? It could go much higher and even beyond the breakdown voltage of the rectifier. In other words, if it could stand 50 volts without burning up, look how close you came.

Besides that, the tests are meaningless unless it is connected.

As said, disconnect the rectifier completely and check all the diodes, both forward and reverse polarity.