2005 Johnson 90 OSI No Spark

[cary00silve]

It is not unusual to see some voltage drop, when cranking the motor. If the yellow/red wire has less voltage than the battery than there is an issue.

Good batteries, good starters and good wiring would limit the voltage drop to 10.5 volts or so. See what you have.

Ok, so I went through the CDI guide for checking connections and terminals. Had some corrosion, so I cleaned things up really well. Now, the total V drop on the POS line from battery to starter is 0.4V when cranking, and 0.3V on the NEG side when cranking.

Still no spark, though. The voltage at the battery dropped to around 10V when starting, and the yellow/red wire was about 8.5V. I verified this with a remote starter as well to rule out the boat harness. Should there be that much of a drop across the solenoid?

I pulled the starter, and just spinning the starter, the battery voltage dropped from 12.3 - 11.5. I'm still quite confused as to what the problem could be. The starter and solenoid looked pretty new, too.

 

[cary00silve]

I just went outside again to probe some more. I've been through EVERYTHING on the motor, so I figure I would focus on the boat side wiring and the ignition switch. One thing that stuck in my mind was that I saw some slight voltage on the black/yellow kill wire with the key in the ON position.

I probed the different wires on the outboard side of the boat harness with the key in the OFF and ON position WITH and WITHOUT the safety lanyard attached.

One thing I noted was that there was continuity between the black/yellow kill wire and the black/white ground wire with the key OFF and the safety lanyard REMOVED (as it should be). However when I turned the key to ON with the safety lanyard REMOVED, there was no continuity. Obviously the switch is busted in some way because there should be continuity without the lanyard attached.

I couldn't find any other things that weren't as they should be, but nonetheless it has me questioning the ignition switch.

Am I missing something, or is this logic sound?

 

[jakedaawg]

However when I turned the key to ON with the safety lanyard REMOVED, there was no continuity. Obviously the switch is busted in some way because there should be continuity without the lanyard attached.


Am I missing something, or is this logic sound?

That may or may not be correct thinking...

On one version of the safety switch when the lanyard is removed the key pops out and it only briefly switches to ground. On the other version of stays to ground. I cant remembe the years.

Anyways, in the sticky at the top of the forum section there is a useful "key switch test" section. I believe it covers.kill switch as well. If not post back and I'll pull the manual out and post it...

 

[cary00silve]

That may or may not be correct thinking...

On one version of the safety switch when the lanyard is removed the key pops out and it only briefly switches to ground. On the other version of stays to ground. I cant remembe the years.

Anyways, in the sticky at the top of the forum section there is a useful "key switch test" section. I believe it covers.kill switch as well. If not post back and I'll pull the manual out and post it...

Thanks, but I couldn't find that sticky

 

[jakedaawg]

I'll grab the manual when I go down to the shop...05 looper?

 

[jakedaawg]

You are testing for spark with all plugs removed and key in the run position, correct?

 

[cary00silve]

You are testing for spark with all plugs removed and key in the run position, correct?

I've done testing with all the plugs removed, and without all the plugs removed. When I've had the boat harness attached, I've had the key in run/start and the lanyard attached.

Yes, its a 2005 90hp V4 2 stroke

 

[cary00silve]

So I called CDI again this morning, and they are thinking either the optical sensor or the "NEW" power pack is bad. Their rationale is that the stator power coil is putting out 17V to feed the power pack, which is plenty. However, the optical sensor input is only 9.8V (lower spec is 10.5V) and the optical sensor output is 7.25V (lower spec is 8V). According to CDI, the OE optical sensor (which is what I have) won't fire below 10V, but theirs will. They also seemed concerned that the V differential between input and output on the sensor is 2.5-2.6V. Apparently, it should be around 2.0V, but no more than 2.5V. I ordered a new optical sensor (with same day delivery from Amazon) so we'll see if that does it.

 

[clanton]

Yellow/Red is starter wire, should have battery voltage when starter engaged with ignition switch. Post # 10 how are you connection the meter, should be read lead to primary/hot side. black wire to ground.

 

[cary00silve]

Yellow/Red is starter wire, should have battery voltage when starter engaged with ignition switch. Post # 10 how are you connection the meter, should be read lead to primary/hot side. black wire to ground.

The yellow/red starter wire is always about 1V less than the battery voltage when I'm trying to start the engine. I followed the CDI troubleshooting guide and connected a 12V source to this wire when using the remote starter, but it made no difference.

For post 10, I did as you say, and connected the red lead to the orange/blue or orange/green wire, and the black lead to ground. No DVA signal was observed on any of the four coil wires.

 

[jakedaawg]

 

[cary00silve]

IT WAS THE OPTICAL SENSOR!!!!!

The low voltage made CDI suspect that it wasn't triggering. Amazon had same delivery of one, so I bought it and plugged it in. Immediately had spark. Now it's running like a champ!

Thank you so much to everyone who chimed in with help. I'm also very grateful for all the support CDI provided. Their tech support is incredibly helpful.

Thanks!!!!!

 

[rothfm]

Appreciate following up with your Fix, so we all learned something too! Sweet. Congrats.