No spark on cylinder #1 1983 Johnson 75HP

[kevdog2000]

Took the boat out and it wouldn't run above an idle. Any throttle movement caused the motor to stall. I took it home and found that I'm not getting spark on cyclinder #1 but 2&3 had spark. I switched plugs and wires and had the same problem. I, then switched the orange coil wires on #1 and #3 coils and had spark on #1 and 2, nothing on #3. This told me the problem was before the coil, possibly the power pack or stator. I took a chance and bought a power pack. (Tried to do voltage checks according to manual but don't have a DVA meter, so results weren't accurate).

i hooked up the new power pack and found that I now only had spark on #3. Called the place where I purchased the power pack and they told me to recheck everything and how the pinouts should be at the connector to the coils. If it still didn't work they suggested retrying the old power pack to determine if the original results returned. Also, they said they've had new power packs that were bad and were willing to replace the defective(?) one.

Here's the weird part...when I put the old power pack back on I now had spark on #1 and #3 with nothing on #2! My question is twofold...is it still possible that the power pack is the problem or are the differing results from all the swapping pointing to a different solution for the no spark on one cyclinder?

Any help would be greatly appreciated!

1983 Johnson 75HP J75TLCTE

 

[Bosunsmate]

electrics do weird stuff.
have you ohmn tested your stator and timing base wires?
Also clean all the ground bolts and threads, corrosion in them is a spark killer

 

[SparkieBoat]

sounds like a power pack, but you can follow the instructions in my sig below to find out for sure.. easy stuff

 

[kevdog2000]

Thanks for the responses! I haven't ohm tested the stator or timing base wires. I'll try that today using link supplied by SparkieBoat and my manual along with rechecking the ground wires. I'll post back with results.

 

[kevdog2000]

Update: Ran through the ohm testing with the following results:

Charge Coil Resistance Test 1 - resistance between wires on two prong plug won't stabilize. Meter reading just keeps climbing
Test 2 - no reading movement when grounding black lead of meter and touching A then B with red

Sensor Coil Resistance Test 1 - white to blue = 9 ohms
white to green = open
white to purple = 9 ohms
Test 2 - no reading movement when black lead grounded to timer base and red touches A,B, C and D

Is it correct to think the sensor coil readings are the problem since white/green test is open or charge coil problem since the reading won't stabilize?

 

[SparkieBoat]

I have not had much success with OHM test on outboard electronics. comes in real handy with finding a bad wire or connection but DVA test are the most reliable. less than $30 for an adapter that will work with your meter.

 

[Bosunsmate]

Update: Ran through the ohm testing with the following results:

Charge Coil Resistance Test 1 - resistance between wires on two prong plug won't stabilize. Meter reading just keeps climbing
Test 2 - no reading movement when grounding black lead of meter and touching A then B with red

Sensor Coil Resistance Test 1 - white to blue = 9 ohms
white to green = open
white to purple = 9 ohms
Test 2 - no reading movement when black lead grounded to timer base and red touches A,B, C and D

Is it correct to think the sensor coil readings are the problem since white/green test is open or charge coil problem since the reading won't stabilize?

is white to green went to be open?

 

[kevdog2000]

Bosunsmate:

Might have used the wrong term...at the start of testing my meter reads 1 on the left of the display, when putting probes on white/blue meter display changes to 9.05 , white/green meter doesn't change and reads 1, white/purple meter display changes to 9.02. Assumed since no change occurred on white/green then it was open (total resistance?)

hope this clarifies things...

 

[Bosunsmate]

Bosunsmate:

Might have used the wrong term...at the start of testing my meter reads 1 on the left of the display, when putting probes on white/blue meter display changes to 9.05 , white/green meter doesn't change and reads 1, white/purple meter display changes to 9.02. Assumed since no change occurred on white/green then it was open (total resistance?)

hope this clarifies things...

Yes thats not on. Looks like a fault, sometimes it just one of the wires that have snapped between the connector and the sensor, i suggest you check those out before replacing the whole thing

 

[kevdog2000]

Just an update...put the replacement power pack on yesterday and still had no spark on #2. Going to pull the timer base to see if the green wire has a break in it. If not, going to get a replacement. Will post results.

 

[SparkieBoat]

a $30 DVA adapter would help you to find the bad part, but If you are going to replace the timer base you should just go ahead and do the stator and rectifier/regulator while you have it apart. then you have all new electronics and keep your old ones for spares.. I would ohm test the ground for the powerpack and for the #2 coil test to the battery ground. there should be no resistance. I thought you originally had no spark on #1,

 

[kevdog2000]

SparkieBoat: I will recheck the ground on the power pack and coil. The suggestion about the stator replacement is food for thought since I'm there anyway.

In regard to the "no spark" condition, you are correct, when I first found the problem, I had no spark on #1. After testing and swapping plugs, wires, coils, etc. the no spark condition "moved" to #2 cylinder, which confused the heck out of me. The only consistent piece is the open on the white/green test. I have continuity on the green wire from the connector to the timer base which tells me the wire doesn't have a break in it and that's why I was going to replace the timer base.

This next question is asked out of a lack of understanding electrical testing....How does the DVA test identify the bad part?

Thanks again to both of you for helping me with this problem!

 

[SparkieBoat]

click on the CDIelectronics link in my sig. a free guide to troubleshooting your motor and DVA readings. a little confusing at first but you will get the hang of it. there is a link to a DVA adapter too. but you can order it from many other sites for about the same price just google it. I ordered this one and have been using it for years. the only way I know to accurately diagnoise outboard electronics.

 

[kevdog2000]

Got some good news today! Put the timer base on and reconnected everything and I have nice blue spark across all cylinders! Just have to put it all back together, test in the driveway and hopefully get out fishing this weekend. Thank you to SparkieBoat and Bosunsmate for helping me out!

 

[SparkieBoat]

I am glad you got it going.