no spark

[dstarok]

I have no spark on any cylinders on my 1994 200 HP Mariner. Trying to find the cause.
Does this sound right? According to my Mercury manual, the Black/yellow wires come from the switch boxes and join with:
1) the black/yellow wire from the other switch box and
2) the black/yellow wire that goes to the"Mercury/Tilt " switch and
3) the black/yellow wire that goes to the ignition switch.

The tilt switch closes when the motor is tilted or kicks up, shorts to ground and kills the engine.

The ignition switch, when in the off position, completes the circuit from the black/yellow wire to the black wire which returns to the engine and goes to ground and kills the engine.

Either of these being faulty would result in no spark, correct?
I do not have a tilt switch installed, and checked the ignition switch to be open between the black/yellow and the black when the switch is in the run position. I also removed the black/yellow from the outer switch and turned the motor and had no spark from the plug associated with that switch. (Starboard side cylinder)
What do you think is causing me to have no spark? I don't think both switches went bad simultaniously. My stator seems to have good readings.
Thanks for any info,
Dave

 

[Wreck Rider]

Re: no spark

Your logic is sound but I think "mercury/tilt" refers to "the mercury switch that senses the motor is tilted" rather than a tilt/trim system that your post suggests.

Sorry can't be any other help as I'm not familiar with this system except in theory.

 

[dstarok]

Re: no spark

Your logic is sound but I think "mercury/tilt" refers to "the mercury switch that senses the motor is tilted" rather than a tilt/trim system that your post suggests.

Sorry can't be any other help as I'm not familiar with this system except in theory.

 

[jtexas]

Re: no spark

"either being faulty would result in no spark" correct. Wreck sounds true, a mercury switch would detect tilt.

Possible the kill wire might have got rubbed bare and grounded out somewhere? not sure your model, if you can, best to disconnect it at the powerpack and try again.

Try this ignition troubleshooting guide for testing stator, powerpack:
http://rapair.com/Portals/0/downloads/TroubleshootingGuide.pdf

 

[dstarok]

Re: no spark

Thats a good troubleshooting site. I have found that both switches are getting ggod voltage from stator but not outputting to the coils. Everything points to 2 bad switches. I thought I read in a post a few days ago about what could cause both switches to fail, but can't find it using search feature. Any ideas? Bad trigger?
Thanks,
Dave

 

[rivercookdave]

Re: no spark

check the fuse on the engine,it is an inline fuse,right side near the top of the engine.

 

[dstarok]

Re: no spark

Fuse is good
Thanks

 

[sleepinin]

Re: no spark

Dave,
The trigger tells the switch boxes when to release the charge to the coils, but the trigger has 3 coils so all three coils went bad? Both switch boxes bad? You say you don't have a mercury tilt stop switch? Was it removed? and if so what happened to the wire that used to connect it? Could it have come in contact with engine and grounded out? The tilt stop switch should be above your switch boxes to the right by the starter solenoid. I think it's copper or silver metal capacitor tube looking thing that has one fin that it's mounted by. If you find it let me know and I'll tell you how to test it. Also I'd check the trigger link rod to see if it came loose. Can you move the arm attached to the trigger link rod or is it stuck?

 

[dstarok]

Re: no spark

Sleepinin.
Thanks for your reply. I replaced a tilt switch on my last motor (88 150 Merc) when it went bad and shut me down, so I am familiar with it and it's purpose. It had already been removed from this motor when I bought the rig. The wires that went to it appear to be well taped up. I turned the ignition switch to on, and read resistance from the black/yellow wire(s) to ground, and it read 59 ohms. I am guessing that is reading through a coil, not a dead short. I really don't know anything about the trigger. I just went out and moved the lnk rod where it attaches to the spark advance lever. It will move, it's not stuck. It moves the trigger assembly slightly when I wiggle it. I stated previously that 2 months ago the motor broke down and I limped in on 3 cylinders. I took it to the shop and they replaced 1 switch. When I took it out Satuday, I went over a big yachts wake and thats exactly when the motor died. I have read some things about bias(?) between 2 switches and that needs to be checked when you install a new one. Different resistances between the 2 switches and ground will result in ruining them both I believe it said. I haven't checked the resistances to ground, I forgot where I read that and don't know which terminal to read to ground, or even if that really makes any difference. I can understand circulation currents possibly having an effect on the switches. Thanks again for any info.
Still trying to find the answer,
Dave

 

[sleepinin]

Re: no spark

Dave,
Since you can't run the motor your kinda stuck with Ohm Test. To check the switch box bias set your ohm meter to 1k scale. Leave everything connected on your switch boxes. Zero out meter then put a probe on the switch box top left terminal (wht/blk) and the other probe on a good ground like at your starter. Should get a reading of 1300 to 1500 ohms. If not one or both switch boxes are bad. If you get a bad reading you need to disconnect idle stabilizer or spark advance module (whatever you have) and do it again to rule them out. To check your trigger set your meter to Rx100. Remove all trigger leads. Test between Brown(without yellow sleeve) and white(with yellow sleeve). Test between white(without yellow sleeve) and violet (with yellow sleeve). Test between violet(without yellow sleeve) and Brown (with yellow sleeve). All test should be between 1100 and 1400.

 

[dstarok]

Re: no spark

I'm reading an open (no continuity) between the White/ black on the top left terminal on the switch box and ground. I don't have an idle stabilizer or spark advance module.

 

[dstarok]

Re: no spark

Oh, also, trigger readings are good.

 

[dstarok]

Re: no spark

OK, I read this on the Outboard parts.com Troubleshooting page, info supplied by CDI / Rapair

Quote: "Always check the bias circuit: Disconnect the jumper between the packs on the white/black posts. Check the resistance from the white/black posts on each pack to engine ground. Standard packs will read from 13-15,000 ohms. Racing boxes will read approximately 9,600 ohms. MAKE SURE THAT THE BIAS READING IS THE SAME ON BOTH PACKS!!! If the bias is out of specification on one pack you must replace both packs to prevent future damage. This circuit effects ignition timing and could cause a powerhead failure.
For more detailed information, please refer to the troubleshooting guides on the other pages."

I tried this again with my meter in a higher range and got good readings, 14000 ohms each with white/black disconnected, and 7000 ohms connected. This seems to be ok. (the sum of 2 resisters in parrallel would be 1/2 the value of 1).

 

[dstarok]

Re: no spark

Anymore ideas?

 

[Plainsman]

Re: no spark

I am not familiar with your motor, so take this with a grain of salt, but this was one test for my motor.

do you have 12V to the red terminal on the switch box?

do you have 12v at the white terminal when the key is turned on?

 

[mikael.block]

Re: no spark

hi
Just a wild guess...

You say that it happend after a big wave....

I think you brook something.....

mikale

 

[sleepinin]

Re: no spark

Do you have a Direct Voltage Adaptor? (DVA) or a or a multimeter with a DVA built into it? There's other test to find this but you need a DVA. There is one that you need to do to either isolate this to the ignition system or the switches like your ignition, wiring, tilt cutout, etc. I'd also check all your grounds, which you probably already have.

 

[jtexas]

Re: no spark

Only other thing I can think of, not mentioned yet is flywheel magnets.

How did you verify output from stator and no output from powerpacks?

 

[Laddies]

Re: no spark

With the black/yellow kill wires removed from the boxes, with a DVA there should be 180 + volts on the blue wire at the boxes ans 30+ volts on the red wires if not the stator is bad if you have the voltage and no spark disconnect the yellow wires from the rectifier, if you have spark then replace the rectifier

 

[sleepinin]

Re: no spark

I went back looked at the test procedure for switchbox bias test and the first thing they say it so disconnect the white/black from the terminal. Sorry for the bad Advice, I must have had the voltage test on my mind or something. You mentioned you don't have a idle stabilizer or spark advance module, I'm wondering what your white/black wire goes to. Could it be a shift interrupter switch? Maybe this went bad causing a permanent interuption to your switch box operation. You might try unplugging it and see if you get spark or do a negative voltage test by setting your voltage meter to 20vdc scale, put black probe on your white/black terminal and the red probe on the ground. You should get 1 to 6 volts if your starter can crank at 400 rpm.