Dropped spark on cylinder 4

[MillerIsTall]

I have a 1977 Johnson 85 outboard that is not producing Spark on cylinder 4. At the beginning of the season I would store the motor tilted all the way up as I was fairly close to shore. When I would take it out it would not seem to want to fully open up for about 10 or 15 minutes. Thought maybe it was flooded from storing motor tilted. As I would be driving the motor would kick the full power and I would be good for the rest of the day. Last week I took the boat out and it was running fine and after about a half an hour of driving I lost power like I previously mentioned. I clean the carburetors thinking I may have sucked up water and cleaned it fuel lines completely along with the tank. Took the boat back out and it was still performing the same. Went to do a compression test and noticed cylinder for spark plug was wet and fairly clean. Compression test was even on all cylinders. Did a spark plug test and was getting no spark from number 4. Spark plug works in the other three Leeds. Changed the coil pack and problem was solved....for the day. That was yesterday. Today went to take the boat out and it's doing the same thing, no spark on cylinder 4. What should I look for next? CDI?

 

[havoc_squad]

I have a 1977 Johnson 85 outboard that is not producing Spark on cylinder 4. At the beginning of the season I would store the motor tilted all the way up as I was fairly close to shore. When I would take it out it would not seem to want to fully open up for about 10 or 15 minutes. Thought maybe it was flooded from storing motor tilted. As I would be driving the motor would kick the full power and I would be good for the rest of the day. Last week I took the boat out and it was running fine and after about a half an hour of driving I lost power like I previously mentioned. I clean the carburetors thinking I may have sucked up water and cleaned it fuel lines completely along with the tank. Took the boat back out and it was still performing the same. Went to do a compression test and noticed cylinder for spark plug was wet and fairly clean. Compression test was even on all cylinders. Did a spark plug test and was getting no spark from number 4. Spark plug works in the other three Leeds. Changed the coil pack and problem was solved....for the day. That was yesterday. Today went to take the boat out and it's doing the same thing, no spark on cylinder 4. What should I look for next? CDI?

When the issue occurs, you need to check with DVA meter/DVA multimeter adapter the voltage level to primary side the coil (Not the coil to spark plug). Then compare it with the factory service manual specifications on what is the acceptable voltage range.

When you get a no spark situation or suspect spark is dropping, this is the test you need to do first.

If you get the required voltage to coil but no spark, you either got a ground issue, a coil issue, a plug wire issue, or a spark plug issue.

However, if you do not have the minimum voltage level being supplied to the coil and ONLY that cylinder's coil getting low voltage while the rest are within spec, then you're looking at a power pack, pickup coil, or inner flywheel magnet issue.

I would be concerned about ignition coil grounding failing if you swap the coils and the issue follows the coil if you bought Evinrude OEM. Do you have the grounding washer and flat washer attached to the ground section of the coil properly?

 

[MillerIsTall]

When the issue occurs, you need to check with DVA meter/DVA multimeter adapter the voltage level to primary side the coil (Not the coil to spark plug). Then compare it with the factory service manual specifications on what is the acceptable voltage range.

When you get a no spark situation or suspect spark is dropping, this is the test you need to do first.

If you get the required voltage to coil but no spark, you either got a ground issue, a coil issue, a plug wire issue, or a spark plug issue.

However, if you do not have the minimum voltage level being supplied to the coil and ONLY that cylinder's coil getting low voltage while the rest are within spec, then you're looking at a power pack, pickup coil, or inner flywheel magnet issue.

I would be concerned about ignition coil grounding failing if you swap the coils and the issue follows the coil if you bought Evinrude OEM. Do you have the grounding washer and flat washer attached to the ground section of the coil properly?

Yes it is properly ground. I don't have a DVI meter so I guess I did the next best thing bye swapping sensor #4 & coil #4 wire with # 2 sensor & coil wires. The problem followed so I'm assuming it's the power pack. Cylinder #4's spot on the power pack is dead. Would I be assuming correctly?

 

[MillerIsTall]

This is what the power pack looks like on mine

 

[Faztbullet]

Take your spark tester and swap coil output lead from #4 to a know working cylinder(org lrads) . If it sparks and other lead stops replace pack