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Rectifier Test Reading? 1980 Johnson 115 V4 2 Stroke

Popeye_1425

Popeye_1425

New member
Greetings. I'm having a fit trying to get a tach to work on my 1980 Johnson. It did not come with one from the factory apparently.
What I've done:
Bought a cheap tach (1st mistake) and wired it correctly. Did not function. Tested the rectifier and it tested bad. I was getting readings in both directions on the ohm meter from both yellow wires.
I replaced the rectifier and tach worked as long as I held my finger down on the positive lead that connects to cheap tach.
Bought a Faria marine tach. Connected correctly and pole settings are as described in the directions but tach does not function. I put the cheap tach back on and it did not function. There is power to the tach. It appears as if the tach is not getting information from the gray source wire that ties into the rectifier at the junction bar.
Using a Cen-Tech Multimeter set at 200k diode I tested the new rectifier. When I place red lead from meter on each yellow wire and the black lead from meter to rectifier case, I get reading of 1 on both yellow wires. Which I should. (Right?) When I switch the black lead from the meter to each yellow wire and the red lead from the meter to the rectifier case I get two readings. One yellow wire measures at 84.5 while the other yellow wire reads at 64.9. both readings seem stable. Is there too much deviation between the two yellow wires readings? Is this causing my issue. If not, where else should I starting looking? Any input would be much appreciated.
 
Remove yellow wires from terminal block.-----Put ohmmeter on the yellow to yellow on stator.----What is the reading ?----Put ohmmeter on one yellow and ground.----What is the reading ?
 
As I look at the wire diagram,( attached) I see one yellow wire from the stator and the other is a gray and yellow. Is those the ones you are talking about?
 

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I don't know that I'm doing it correctly. I'm testing in the same manner as I did the rectifier. In any case, when connecting yellow wire from stator to ground - I get no reading. Tested same yellow stator wire against both yellows from rectifier - no readings. Again, not sure that is what you instructed.
 
No marine shops in my area. It be easier to pull the stator itself. I could replace it for $175. Just hate to if uncertain...but my frustration has a tendency to over power my wallet...😀
 
I know you said to ignore the gray/yellow wire but it is the only other wire that comes out of the stator that connects to the terminal block. I tested between it and the only yellow wire coming from the stator. I get a quick reading but abruptly goes to 00.0.....does that mean anything? no readings when test ground.
 
???---One meter probe on yellow------Other probe on other yellow.-----What is the reading and are you using a digital meter ?
 
Yes....using digital meter, but there is only 1 solid colored yellow wire coming from the stator to the terminal block.
 

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Did you read post #5 ??-----I likely have more than 1 stator to fit your motor !---Years of experience.----Run to a shop and have this simple test done.
 
Yeah.....I read post #5 but no marine shops nearby me. Nearest probably 2 hours. As I was looking at replacement stator to compare with the one that is on mine.....the replacement has 2 yellow wire but no yellow/grey wire. I've been sitting pondering all the hurdles I'll run into pulling that flywheel. I have the tools but I just know that thing is probably rusted on for more than 40 years. Motor cranks and runs fine. Have been concerned about charging. Never had the battery drop below 12.4 but never seen it charge into 13s either. What to do what to do....:unsure: Pretty sure 10amp stator. Part # 583672
 
OK....the tach is working. What I did:
I noticed the the rectifier sits awful close to the yellow and gray wire which joins the grey source wire for the tach and the yellow/grey wire is frayed at the end. Maybe its arching. I used to race motorcycles and had a similar issues related to a spark plug wire while racing at Daytona one year.

I also had the tach spliced into the instrument panel and I know it had power because the lights of the tach came on and the needle would move slightly when I turned the key. I hooked it up directly to the battery and the source wired is joined to the grey wire at the terminal block. In any case, the damn thing is working. If it is accurate, the motor is idling way to fast at 2000 + rpms. The idler screw is turned all the way out. Could this be a lean fuel issue? I have also on occasion, it first start up after sitting a while, had the motor sneezing at idle. However, when I rev it up it cleans up. When returned to idle position it does not seem to continue doing it or at least not as bad. The motor has a type III carb, so there is no fuel/air adjustments. Time to break out some carb cleaner maybe?
 
After thought:
In addition, regarding the testing of the stator, I read some other post regarding similar things. I believe I had the multimeter on the wrong setting. When testing yellow and yellow/grey wire I got a reading on 003 and 0 when yellow against ground. Is there a way to test the yellow wire and the yellow/grey wire for how much voltage its producing while the engine is running?
 
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