Testing the Charging System - 1970 Evinrude 40hp Lark Elect Shift

[jwh114]

Wondering if anyone can give me some insight. I'm not convinced the charging system is charging the battery on my Evinrude outboard (model 40072A) and would like to test it to confirm.

When I purchased the boat, the owner had removed the dash panel with ammeter and rewired to bypass it (to install a stereo). I have since removed the stereo and reinstalled the dash panel and restored the wiring back according to the wiring diagram for the motor. I expected to see the ammeter show a reading while the boat was running at full throttle but it stays at zero. So, either the ammeter is busted or the charging system isn't functioning.......

This is what I have determined so far:

-I applied a voltmeter to the battery with the engine off & again at full throttle. I get the same reading either way (12.44V) which suggests to me there is no charging happening.

-I have checked the terminals on the generator to confirm the field and armature wires are connected to the correct terminals on the voltage regulator.

-I have connected the generator to the battery as described in the SELOC manual and it runs.

-I noticed the needle on the ammeter will move very slightly past zero in the negative direction while engaging the starter to turn the motor on.

-Belt is nice and tight.

I assume based on the above the generator is functioning. My questions is how do I rule out/test the ammeter and the voltage regulator? Or could it still be a problem with the generator?

SELOC also mentions to check the fuses. When I pulled the cover off the regulator I didn't see any. I'm kind of confused about that but maybe fuses were only for older models?

I apologize in advance if these are dumb questions or if I've completely missed the boat (no pun intended) on this!

Any help, advice or direction is much appreciated....

 

[charliedaubitz]

Re: Testing the Charging System - 1970 Evinrude 40hp Lark Elect Shift

I fixed my old 69 regulator that had sat for 30 years by pulling the rusted cover off and cleaning the points on the coil next to the bat terminal, use a ohm meter to check continuity across the points when they are closed by pushing on them with your finger. I guess they oxidize after a few years, I cleaned on mine quite a bit before it would show closed on the meter.
I painted the cover while it was off and now it looks and works like new.

 

[wilde1j]

Re: Testing the Charging System - 1970 Evinrude 40hp Lark Elect Shift

Are you sure you installed the ammeter correctly (in series in the 12 V line)?

Very easy to check if the motor is charging ... measure across the battery terminals with the motor running at a fast idle. => than 13.5 VDC is ok. Anything around 12.8 VDC or < is NG.

 

[F_R]

Re: Testing the Charging System - 1970 Evinrude 40hp Lark Elect Shift

Are you sure you installed the ammeter correctly (in series in the 12 V line)?

Very easy to check if the motor is charging ... measure across the battery terminals with the motor running at a fast idle. => than 13.5 VDC is ok. Anything around 12.8 VDC or < is NG.

The DC generator won't do anything till the motor is running about 2000 RPM. But he says he is getting nothing at WOT.

There is no field fuse on the 1970 models.

You motored the generator and it passed, right? You had the polarity correct, right? The generator should be ok.

Your ammeter showing a slight movement while starting indicates that it is working.

Assuming your wiring is correct (?), your regulator isn't working. OR, somebody has slapped in a car regulator??? They are NOT all alike!!

Is your regulator mounted below the carburetor where it is supposed to be? I only ask because it has to be grounded.