1996 johnson 25 hp no spark

[maineiac5586]

Hi, I have a 1996 Johnson 25 2 stroke 2 cylinder (yeah one of the bulletproof models), anyway I have no spark. I followed the repair manual and the only questionable test I hit was for the repair manual calls a sensor coil. when I tested between terminals b and c as the book states my meter singaled an audible continuity alarm. my ohms reading was 38 on the 2000 ohms scale and the book says it should be 40 + or - 10 ohms.(if I was on the right scale on my meter than my ohms reading sounds fine but what about the cotinuity between thos two terminals. (again, I had one lead from my meter in the hole terminal b and one lead in hole terminal c and repeated getting continuity between those terminals. The next part of that test says to check for grounded condition connect ohmeter between terminal b and ground and repeat for terminal c and ground. My meter read zero ohms when doing this test for grounded condition which is passing as per the repair manual. So, does the continuity between those two terminals seem right or wrong? Anyone know what I should do next? I have no spark output from either spark plug wires (coils have been checked, spark plug leads have been checked, stop circuit has been tested, all as per the manual), anyone have a clue? please help me if you can thanks

 

[Bosunsmate]

Re: 1996 johnson 25 hp no spark

Have you checked the stator?
38ohmns sounds good.
Its not trying to spin backwards is it?
Have you checked the sensor dc voltage?

 

[maineiac5586]

Re: 1996 johnson 25 hp no spark

This is a manual start motor so no 12 volt battery hooked up to it. Can you explain how exactly to check the sensor dc voltage? or how to check stator. I just checked the kill switch again and did as the book stated which is to put one tester lead from the meter into the e terminal and one to ground and the meter should read a high reading (my meter displayed the digit 1 before and during the test no matter what scale I used and I confirmed this on another meter as well (is that passing this test?) when I pressed in on the kill switch as if to stop the motor my reading displayed around 38 or so and my continuity beeper sounded.) I may be in over my head but this seems like such a simple motor I really would like to figure this out, thanks

 

[Bosunsmate]

Re: 1996 johnson 25 hp no spark

read brown to brown yellow. It should be 900-1200 ohmns
read orange to orange black. It should be 50-60 ohmns
To check the voltage you will need a meter that measures peak output
Your kill circuit sounds ok, you should get 1 when the leads arent touching anything too then ie its saying its an open circuit

 

[Bosunsmate]

Re: 1996 johnson 25 hp no spark

read brown to brown yellow. It should be 900-1200 ohmns
read orange to orange black. It should be 50-60 ohmns
To check the voltage you will need a meter that measures peak output
Your kill circuit sounds ok, you should get 1 when the leads arent touching anything too then ie its saying its an open circuit

 

[maineiac5586]

Re: 1996 johnson 25 hp no spark

did the test, brown and brown yellow read 850 ohms (under your spec), I do not have orange colored wires to test so not sure about that. Any thing else to try to get this thing going? any common things to look for on these motors under this condition?

 

[maineiac5586]

Re: 1996 johnson 25 hp no spark

UPDATE, I transfered the trigger and the sensor from a 1988 evinrude 9.9 to my motor and tried again. No spark still. I transfered the power pack from the 9.9 and it started right up. I switched back to the original powerpack and again had no spark. Lastly, I switched back to the 9.9 powerpack and it ran again. (so, I know I cheated and threw parts at it but it was too tempting as I had them laying around. Now the question is do I leave the trigger, sensor and powerpack from the 9.9 on my 25 hp? The part numbers were the same for the sensor but the trigger and the powerpack have different part numbers. Does that fact that it runs and revs up mean it is ok to leave those parts in there or am I leaving something on the table by not putting the specific 25 hp parts in it? Last question, the trigger on the 25 hp has a metal shield around the pickup magnet while the 9.9 coil doesn't. Does this matter? Please let me know the answers to my questions so I can wrap this up. Thanks

 

[Bosunsmate]

Re: 1996 johnson 25 hp no spark

850 is ok. that wont be causing your problem.
Check your timing with that new gear. It may be running but if its far out on timing you will ruin a piston or two.
If its close to the timing required then go for it, youve beaten the pricing system

 

[maineiac5586]

Re: 1996 johnson 25 hp no spark

Not sure how the timing could be thrown off because I didn't mess with the adjustable plate or any timing parts. I simply changed the powerpack, sensor and trigger all with parts from a 9.9 evinrude. I am just looking for input on if the motor starts and runs and revs up freely if I am ok leaving the 9.9 parts in there. If anybody has any input or history doing what I did please let me know, I would hate to get out on the water and experience an issue. thanks

 

[Bosunsmate]

Re: 1996 johnson 25 hp no spark

All those parts not being the specified one for the motor have the huge potential to change the timing of firing pulse