1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

[SteveYo]

Hi, It's a Merc 100hp 4 cyl 1994 2+2 serial #d197153. I've been through the motor trying to get spark out of the bottom two plugs. Swapping over leads from the coils to the switchbox will get the opposite two to spark. Swapping over the trigger wires on the switchbox doesn't get the bottom 2 sparking. As far as swapping over wires from the stator, here I am puzzled, from the stator comes only four wires, a grn, a grn and wht, two yellows. The yellows go on to the rectifier and power plug. The grns come back toward the switchbox, go into a sealed hotdog sized box strapped on by the switchbox, the wires then come out of the sealed box blu/blu and wht. These blu wires then attach to the switchbox. There are no red, red wht partners to join the blu on the switcbox. The bolts for reds are there with caps screwed on. I attached the blues to the reds post, no change, no spark to bottom two. I'm trying to figure out what might be going on before I pay for a mech. visit. Thanks everyone, Steve.

 

[rodbolt]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

test the trigger wires. you will need the service manual and a DVM with a DVA adapter.<br /> yours has been updated with the red stator kit.<br /> I suggest a service manual before you tear up a 500 dollar stator or a 160 dollar switchbox.<br />ya just cant switch wiring around cluelessly. makes it that much harder for a tech and more expensive for you.<br />if the top two spark odds are high the stator switcbox charge coils are ok, next step is to look for a trigger input to the switchbox. then for coil prmary voltage out of the switchbox. once you test inputs and outputs the problem is solved.

 

[SteveYo]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

Rodbolt, the stator sure is red, only a blu and blu/wht to the switchbox. Every wire I move is for a test and then I put it back where it came from. So if I test the violet wire, brown, etc.. where the trigger connects to the switchbox and they show juice when I crank the engine, this means the trigger is ok? If I then test grns leaving the switchbox to the no sparking coils this would show the switchbox is bad? Does that sound right. Thanks, a lot. Steve.

 

[SteveYo]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

I lost Rodbolt, my last question was - So if I test the violet wire, brown, etc.. where the trigger connects to the switchbox and they show juice when I crank the engine, this means the trigger is ok? If I then test grns leaving the switchbox to the no sparking coils this would show the switchbox is bad? Does that sound right.<br />Thanks if anyone can help confirm my problem.

 

[rodbolt]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

ya did not lose me, worky worky called and offered me more money per hour than iboats .<br /> I am a hoe ya know.<br />anyway you will need a service manual and a DVM with peak reading capeability. you can do a resistance test on the trigger wires.

 

[rodbolt]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

wrong click, anyway it sounds more like a trigger or switchbox issue than a stator. I dont have that specific manual here at home so I cant tell what the tests are.

 

[SteveYo]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

Thanks Rodbolt, I'm glad you are with it. Steve.

 

[rodbolt]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

repost asking the trigger resistance test for your enigine, am sure someone will come up with a wire color.<br /> for the CDI output if you cannot access a peak reading meter the next best trick is to use the A/C setting on your DVM and take a reading off the known firing inputs/outputs then compare them with the non working ones.

 

[ricksrster]

Re: 1993 Merc 100hp, bottom 2 cyl no spark, tried almost everything.

Resistances for trigger: Brown to white black and purple to white 800-1400 ohms.