omc optical ignition problems no spark help!!

[93dps]

i have a 95 johnson 150 i am having ignition problems with.i have no fire to any of the plugs,ive checked the kill switch circuit,and done most of the electrical checks that i have found in my service manual and on line.nothing is grounded and most of the voltage checks are a little lower than the specs.i only have 9.4 volts when cranking on the yellow and red wire that goes to solenoid and power pack.when i disconnect the solenoid from the starter and turn the key to the start position i have 12.3v.could this be a problem with my starter dragging the voltage down to the point that the pack wont fire?any ideas would be appreciated.

 

[yamamarinetech40]

Re: omc optical ignition problems no spark help!!

Sounds like you do have a problem in your starting circuit, I would start working my way back toward the batt. with the voltage drops....remember that a battery can show really good on voltage and have 'shorted' cell(s). A 'Load Tester" will draw a current(a good model should pull 100 amps) at the flip of a switch and show the result....

 

[Seasport]

Re: omc optical ignition problems no spark help!!

Interesting question. As I think you have figured out, the yellow/red wire provides 12V from the starter solenoid to the powerpack to power the pp electronics during cranking when the power coil is not generating enough volts.

9.4V is pretty low. Should be enough but hard to be definite. You could try a better battery (or even a separate 12V source on this wire).

Have you downloaded the troubleshooting guide form rapair.com? This has a series of tests for no spark.

You may have a faulty sensor or powerpack. Incidentally, I have designed a simple DIY ignition timing analyzer for the OIS sysem. Means you can set the timing statically. Replaces the expensive offical analyzer and pretty easy and cheap to build. I can provide details if you are interested. Would also allow you to check the sensor operation.

 

[93dps]

Re: omc optical ignition problems no spark help!!

ive tried running jumper cables from the trolling motor battery to the main battery,same result.this problem started after the boat sat for a while,it would be hard to get started but once i got it fired up it ran great for the rest of the weekend.then if i let it sit it would be hard to start again.i would pull the plugs and have fire ,but the cylnders would be full of fuel and flooded.now it wont fire at all.i pulled the starter apart and changed the bushings and it seems to turn freely but im not convinced i dont have a problem with the starter or relay.

 

[Seasport]

Re: omc optical ignition problems no spark help!!

Well there's difference between a spark and a good strong spark which will jump 7/16". You may not have been getting a good spark under compression.

I can believe you might get 9.4V measured directly at the starter motor but that's a very low reading at the battery (which is more or less what you are measuring on the yellow/red solenoid wire).
Suggests your battery isn't up to it. Sometimes jumper leads aint so good either as you can get voltage drop across them under high current. Is the starter motor turning over OK?

 

[93dps]

Re: omc optical ignition problems no spark help!!

the starter seems to be spinning pretty good.im going to pull the battery tommorow and have it load tested.i think when this all started i was getting weak or no spark when i fist started cranking on it ,hense the flooded cylnders,ive been chasing my tail on this thing and the only thing that really jumps out at me is this voltage drop to the yellow/red.

 

[Seasport]

Re: omc optical ignition problems no spark help!!

Could still be powerpack or sensor.