1988 Force (US Marine Power) 125 HP - No Spark on all four cylinders.

[PikesPeakBayliner]

Hi Guys,

I've never owned a boat before, but I was given a 1988 Bayliner Cobra by a friend. He said it was just slowly falling apart, and he knew I wanted a fishing boat. It's a ski boat, obviously, but we've had it out twice, and with a couple of changes I think I can fish OK from it.

The problem is that after the second time we took it out, it won't start. It won't fire at all. The starter engages and it turns over easily, quite fast. But that's all. I hooked up a spark plug flasher cable between each plug and it's coil wire, and recorded the neon bulb with my phone while I went to the cockpit and tried to start it. Looking over the videos I took, I only see one tiny flash, but it didn't sound at all like it fired. The one flash makes me think that there might be a frame rate mismatch between my phone's camera and the very quick flashes. But, I only saw one, and it's not firing, so that may not be a problem.

My concern is that all four cylinders are not firing. How common could that be where both modules and/or all four coils go bad at the same time? I checked the resistance of the stator coil and it is in spec, as is the trigger coil.

My question is this. How do I determine if one or both of the modules are bad? I'm pretty technical and have rebuilt one diesel and one gas automobile engines. I've worked with electronics a lot and have only blown up one multi-meter (on a microwave capacitor) so far.

I don't have a service manual for the motor. If anyone knows were to get or download one, I would appreciate the info.

I've posted some pictures and the video with the flash here:

9 new items by Steve Sibert

photos.app.goo.gl

Thank you all in advance!

 

[Nordin]

Outboardpartsdotcom has troubleshoot chart for this ignition system.
As you have no spark at all it sounds like a bad stator cause it is chargning the capacitors in the CDI boxes.
The resistance are in spec, but you have to check the output voltage from the stator. That is more important the the resistance.
To get correct measuring value you need a VOM with a DVA adapter or a VOM that measure DVA voltage but you can use a regular analog VOM and measure the output AC voltage from the stator.
It should put out 200 V or more.

 

[Jiggz]

Make sure the safety lanyard switch is set properly. Don't just look at it, instead remove it and reset it. This is located on the dash by the driver side. It's design for the driver to wear the lanyard while driving and in case the driver gets thrown away overboard, the lanyard will pull out the cut off switch to activate a shut down of the motor.

 

[Nordin]

Have to correct myself.
Outboardignitiondotcom have the troubleshoot chart.

 

[PikesPeakBayliner]

Thank you both. I got a DVA adapter today. Hopefully I'll have time to check the voltages this weekend. I've never used a DVA before. Can it be used with a normal digital multi-meter? That's all that I have.

The DVA came with instructions for testing other motors, but not mine specifically. I'll see if I can make sense of them this weekend, and report back here after that.

Thanks again for your help!

 

[Nordin]

Yes you can use a regular digital VOM with the adapter.
The adapter is just a single diod and a electrolyte capacitor and a resistor.
The diod rectifier the AC voltage (cuts off the negative side) and charge the capacitor over the resistor.
The output from the adapter is the voltage over the capacitor and resistor this so the VOM has time to read the voltage.
The troubleshoot chart at outboardignition has the instruction for testing the ignition system your engine has.

 

[racerone]

Have the battery charged and load tested.

 

[PikesPeakBayliner]

Hi Folks,
I have made a ton of progress with the 125 HP Force engine. I've tested the stator and trigger coils. Resistance is within spec. I purchased a DVA and checked the voltage off the stator, it was 180 volts.

Compression check showed all four cylinders at between 115 and 120 PSI.
When testing the compression, we had all four spark plugs disconnected, and when we cranked it check the compression, all four of the spark plug coils were arcing to the metal holder. That's certainly a good sign!

We did find one of the spark plug wires had a little gash that shocked my friend when we were looking for spark. We taped that up really well and haven't that problem since.

My friend, a diesel mechanic, took off the top carb and checked it over. It needs a gasket kit, but otherwise looked OK. After putting it back on, we stuck the gas hose into a container, primed it, and it started! After adjusting the idle screws by about 1/4 turn, it even idles smoothly, and revs easily.

I don't know exactly what the problem was, but it may have just been out of gas. In any case, it's running better than I've ever seen it run. Thank you all for your help. I'm much more confident and familiar with the engine now.
Noobie status decreasing!

 

[Jiggz]

Congrats on your repair, now you have a better knowledge of your motor than ever. Enjoy!