1974 Evinrude 135 alternator system

[Islandlaker]

My motor is not charging the battery. I have the manual in front of me and to check the rectifier was simple enough and mine tested good. I am confused though with checking the stator. The manual says the first step" disconnect the yellow lead (terminal 5) and yellow/gray(terminal 6) lead at the terminal block. connect the red meter lead to either yellow lead and meter black lead to ground to check for shorts. An infinite reading on HI ohms scale indicates the windings are good. Here is my first question, I can not find a ground wire, in this case are they referring too ground as any piece of metal in the motor? For this test I assumed ground meant a piece of metal in the engine (I touched the black lead to the piece of metal in the engine that was shown to be touching in one of the pictures). The meter remained unchanged at 1 when I did this test. Meaning when I set the meter to hi ohms the meter read 1 and when I did the test it stayed 1.

Test 2: Connect the ohmmeter (LO ohms) scale between the yellow and the yellow/gray leads. A reading of 1.0 ohms +/- .0 2ohms indicates the windings are good, and an infinite reading indicates the windings are open. During this test my reading is 1.5ohms.

So I probably sound like an idiot here but can someone help read my tests for me? To me I think I have a bad stator, but before I spend a couple hundred bucks to replace it I would like someone else's opinion. Also I did the obvious things like check wiring and leads. Everything looks good, looks like someone replaced the wiring in the motor recently as they are all in good shape. The only old looking wiring is the actual battery wires, they look original, but it seems to do the job starting wise at least. Thanks for all the help. I am slowly learning how to work on my motor with your guys help. I have already learned so much. Thanks again!

 

[interalian]

The first test is to see whether the windings are shorted to ground. Any clean metal spot on the motor is OK for ground with respect to the yellow and the yellow/gray. This reading should be the same on the meter as with nothing connected to the meter leads.

The second reading of 1.5 ohms is within the tolerance for low ohms on most digital multimeters.

 

[Islandlaker]

ok great, thanks for getting back to me. So it sounds like my alternator is testing out ok. So what do I do now? if both the stator and rectifier are testing ok, but I still am not getting a charge to the battery. The batteries are brand new. Is it going to be some wire between the alternator system and the battery that is bad stopping this charge?

 

[interalian]

Might want to test the rectifier again. Does your meter have a diode test function? It's a lot easier to be sure you have good readings than using the ohms scale.

Charging also requires good, clean connections at all locations in the system - from the battery terminals to the solenoid, and to the rectifier terminal strips.

 

[Fed]

How do you know it's not charging?
Is it possible something is draining the battery?

 

[Islandlaker]

Fed: I guess I don't know what could be draining it. I only have the motor hooked up to the batter, nothing else. I run my electronics off a separate battery because of this issue. When I am trolling I tend to have to re start the motor every 20 minutes or so because the motor dies when I am in the slowest speed. So after about a day of doing that I get home and recharge my battery and It is reading around 60% after a day of use. Yesterday I ran full speed 15 miles out and then back on lake superior, and trolled between. I figure I would be at a much higher percentage with all the driving around I did.

 

[Islandlaker]

interalian: I rechecked the rectifier and perhaps I was wrong before. I do not have a diode tester so I rechecked with ohms. Step one: Disconnect rectifier leads from terminal block. Connect one ohm meter (HI ohms scale) lead to either yellow or yellow/gray rectified lead, and other meter to ground. Note Meter reading. My meter reading was unchanged 1 when leads touching air and 1 when leads touching as described. (Step 2 and 3 was switching leads around) Switching between leads on both rectifier and meter all came with he same reading 1. Manual says a infinite meter reading indicates the diode is open. A zero reading in both indicates the diode is shorted. A normal diode will show a reading in one directing and no reading the other direction. I have no zeros and no infinites. Everything just read 1.

Step 4: Connect meter between rectifier yellow and rectifier red lead. My meter is in the thousands when I do this test.

 

[F_R]

There are four diodes in that rectifier. All four must be good. You have to test each separately in both directions. That is eight tests. The tests are:

Between one yellow and ground. Expect either a high or low resistance reading
Switch meter leads and repeat test. If it was high before, expect low now, if low before, expect high now

Repeat both tests between other yellow and ground

Repeat both tests between a yellow and red

Repeat both tests between other yellow and red.

Your meter must be capable of diode tests. Not all are.

Make sure it passes all eight tests, and don't bother inventing your own other tests.

 

[interalian]

http://www.repeater-builder.com/astr...de-testing.gif

Yellow wires are "AC IN", red is "POS", case is "NEG".

 

[Islandlaker]

I think I may have found a potential source for draining my battery. When I was trying to start the motor today when I was out fishing the starter was barely cranking even though it had a fully charged battery. After a couple attempts the starter started to smoke. So looks like I am replacing that.

F_R you make it sound way simpler then the manual did. I will try those tests asap.

A unrelated question, but a simple one. My steering rod is bent. Do I have to replace the whole linkage o can I just replace the rod at the end of the linkage?

 

[F_R]

Don't condemn the starter till you check all battery cables and connections. Don't just look at them, take the connections apart and clean them shiny bright, then reassemble tightly.

If the rod coming out of the steering cable is bent, you need a new cable. It does not come apart. Sorry.