anyone have a chart to test charging system on a 91 15hp electric start johnson

[werewolf]

I just got the rest of the parts to put this back together, that boy needs to stay away from outboards / anyway it runs fantastic, but when i put my fluke meter on the battery it was only showing 12.2 volts running at fast idle, shouldnt it be at least 12.8 volts or better, the battery is a older car battery i have for different uses, i just need to see how to test rectifier and stator also.maybe a trouble diag chart .

 

[racerone]

Test the stator.----If it tests good you replace the rectifier.-------What does your ohmmeter read yellow to yellow on the stator ?----Post the number.------What does your ohmmeter read on just one yellow to ground post , that 1 number here.

 

[wrench 3]

Try looking here, http://boatinfo.no/lib/evinrude/manuals/1990-2001johnsonevinrude.html#/170

 

[werewolf]

ok, i will check and write down the readings, and post them,

 

[werewolf]

ok here the test results ,only the yellow/gray and yellow/blue stator wires have 000.8 continuity on them and red has o continuity on anything even to ground , rectifier has 0 continuity on any wires or to ground. see picture for clarity. im thinking its going to be the rectifier as being bad .
the test was done with all wires seperated

 

[oldboat1]

Covered in detail in the oem service manual. Try eBay.

 

[racerone]

Well----That is more information that was asked for in post #2----Means nothing to me with that mess of numbers.

 

[flyingscott]

Replace your Rectifier that motor is only capable of keeping the battery charged. The only way it will fully charge a dead battery is if you run around the lake at full throttle for 5 hrs.

 

[oldboat1]

2-cyl model, I think, from earlier thread.

Try this: https://www.ebay.com/itm/1991-Johns...142852?hash=item48e31051c4:g:i9MAAOSwwI9eiozm

 

[werewolf]

racerone, the numbers are for location , the results are like i wrote , the rectifier has no continuity to any wires on it nor to ground its completely open, the stator has continuity between the yellow and gray marked wire to the yellow /blue marked wire, i know its output is supposed to be around 4/5 amps so im going with a new rectifier on it, and im going to look for a manual .

 

[Vic.S]

racerone, the numbers are for location , the results are like i wrote , the rectifier has no continuity to any wires on it nor to ground its completely open, the stator has continuity between the yellow and gray marked wire to the yellow /blue marked wire, i know its output is supposed to be around 4/5 amps so im going with a new rectifier on it, and im going to look for a manual .

Disconnect all the rectifier and stator wiring to start with.

You should find continuity between all three stator wires.
If you can measure the actual resistances it should be the same between Y and Y/G as between Y/G and Y/B and double that between Y and Y/B, but you cannot measure these low resistances accurately with a multi-meter

You cannot test a rectifier using the ohms setting of a digital multimeter. You must use the diode test setting ( or use an old fashioned analog meter)


Using the diode test setting

clip one meter lead onto the red lead and take readings on the Y, Y/G and Y/B leads You may get readings around 600mV or 0.6 volt or you may get no readings.

Record all three results

Then reverse the meter leads and repeat the above . Record the results

Now connect one meter lead to the rectifier case (which is its negative or ground connection)

Again take readings on the three yellows .... Record the results

Reverse the meter leads and again take readings between the case and the three yellows. Record the results


You should now have four sets of three results ...

You should have one set of three from the first six all reading 600mV and one set of three with no reading

You should also have three readings of 600mV from the second six and one set with no reading

Anything different indicates a failed rectifier

Report your results as a list or table .. not in some incomprehensible form as previously

 

[werewolf]

VIC_S ok ill print this out and check in the morning and see what happens, thanks ,

 

[oldboat1]

wolf:

Use a high ohms setting on your multimeter and test resistance from each lead to an engine ground, then reverse probes. A high reading in one direction and a low reading in the other means the diode is good.

Do the same test between the red lead and each of the other leads (and reverse). Again, a high reading in one direction and a low reading in the other means the diode is good.

(can find this on or around page 8-28 of the manual I referenced above. I think you might be amazed at the info. in there.)

 

[flyingscott]

There are only 2 parts to your alternator. The coils under the flywheel and the rectifier. I have never seen the coils go bad plenty of rectifiers though.

 

[werewolf]

test results

Stator with fluke88 enhanced set on ohms
all wires ,yellow,yellow/g, yellow /b have coninuity to each other , no continuity to grnd on any wires .

set on diode setting , with black lead on grnd, // red lead on grnd
red to yellow =0 // red to yellow =0.507
red to y/g =0 //red to yellow/g=0.497
red to y/b =0 //red to yellow/b =0.512
red to grnd =0 // red to grnd =0

OK VIC.S IS THIS WHAT YOU WANT TO SEE ? im thinking red wire on rectifier is open ?

I have verified all grounds and positive wires on the motor with 0 voltage drop

 

[Vic.S]

You have not done quite what I wanted. I was expecting 12 results but you have only produced 8 and 2 of those, the last 2 are not ones I asked for

If I interpret your presentation correctly the first 6 look fine. All 0 in one direction and about 0.5 in the opposite direction

The last two suggest that the ground connection is open

Please confirm that your rectifier is a 4 wire one and has no black lead

If that is so take similar readings between the case and each of the yellows as you did between the red and the yellows for the first 6.
If the rectifier is good you should get 6 similar readings to the first 6.

If you dont then it is defective

 

[werewolf]

yes it is 4 wires on rectifier, no black leads , ill check again and see what it reads

 

[werewolf]

ok i went back and checked again, red wire is open both ways, only has 0.540 to 0.542 on diode setting all three yellow wires, just put a new evinrude rectifier on it and it shows 4.86 to 4.88 amps at 4200 rpms in gear voltage comes up on battery to 12.8 , but i know the battery is old and its a car battery so im going with it. have another new rectifier on the way for a spare. and no black leads on rectifier, one red, a yellow, yellow/blue, a yellow/gray .

 

[oldboat1]

Try the rectifier test in post 13. Reverse/exchange probes to change direction (test diode in both directions). Note the test method for the red lead.

A rectifier can be destroyed by removing the battery while the engine is running, or by reversing polarity in hooking up the battery (and probably a few other ways).

 

[werewolf]

i replaced the rectifier, works fine now, charges 4.86 to 4.93 average amps, and i know not to disconnect battery while running thanks