70 Mercury 200 20 hp no spark.

carstetj

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May 22, 2013
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Ok, so here is my problem. I have a 1970 mercury outboard 20hp model 200. I replaced the stator and all the wiring on it because it had all gone bad and was corroded and brittle. The motor started right up after putting it back together and ran perfectly took it on the water cranked up first pull every time i tried to start it that weekend. I put it up for the week and took it out this past friday to go fishing. I couldn't get it to start not even act like it wanted to. Even tried a little shot of starting fluid nothing. So I figured for some reason it wasn't getting fuel, that no longer seems the case. Pulled the spark plugs today and grounded them to the grounding screw on the power head with a piece of wire and pulled it a few times. No spark at all on either coil. It has new spark plugs too even went back to the old ones that where working for its first start still no spark. So I pulled the flywheel off to see if something somehow got fried with the stator looks fine all wires look fine. Now for the question, is it possible the new stator fried the coils? I have no idea where to go from here. The coils and the plug wires are the only things electrical i did not replace. Any help or advice would be greatly appreciated, I'm missing good fishing days. Thanks.
 

Laddies

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Re: 70 Mercury 200 20 hp no spark.

Sounds like the insulator blocks where not changed
 

Laddies

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Re: 70 Mercury 200 20 hp no spark.

On the points there is a stud that the wire fastens to and the insulator blocks keep it from shorting, the system is a high voltage ground to fire system and if the blocks are cracked it will arc to ground and cause you all kinds of grief. More stators are changed because of the bad insulator than from bad stators.
 

carstetj

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Re: 70 Mercury 200 20 hp no spark.

On the points there is a stud that the wire fastens to and the insulator blocks keep it from shorting, the system is a high voltage ground to fire system and if the blocks are cracked it will arc to ground and cause you all kinds of grief. More stators are changed because of the bad insulator than from bad stators.

Ok, I know what your talking about. I'll check them, the New stator came with 2 new ones but the old ones looked fine so I just reused them. Thanks for the info I never would have thought of that.
 

carstetj

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Re: 70 Mercury 200 20 hp no spark.

If that was the case, would my new stator be fried now? That wasn't a cheap part and I don't want to replace it again.
 

Laddies

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Re: 70 Mercury 200 20 hp no spark.

No as a matter of fact the way to test a stator is remove the point lead wire from the coil and have someone turn the engine over with the plugs out and clip a jumper wire to the coil and arc it as it is turning and ever time you arc the wire to ground the coil should fire
 

satanclause

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Re: 70 Mercury 200 20 hp no spark.

Would it not be a Good idea to remove the Cable coming from the kill switch when debugging the electrical system?

Could be so easy that the killswitch or it's wireing is faulty!
That would be my first move.

I have a 1968 model 500 and it's switchbox i have as avatar photo in that kill switch goes to blue connector, Brown cable.

Laddies helped me with this just yesterday :)

If this is the problem the Choke works fine as temp killswitch and you can go fishing :)


/Thomas
 
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carstetj

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Re: 70 Mercury 200 20 hp no spark.

No as a matter of fact the way to test a stator is remove the point lead wire from the coil and have someone turn the engine over with the plugs out and clip a jumper wire to the coil and arc it as it is turning and ever time you arc the wire to ground the coil should fire

I'm kinda following what your saying. Is the jumper going to both coils, or just one? I have a manual and it was telling me to test the stator using an ohms meter.
 

satanclause

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Re: 70 Mercury 200 20 hp no spark.

Did you miss my post?
 
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carstetj

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Re: 70 Mercury 200 20 hp no spark.

I did, that was weird I only could see the first line now I see the whole thing. Thanks fir the info.
 

Laddies

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Re: 70 Mercury 200 20 hp no spark.

The green wire is the wire that's jumped coil to coil it supplies about 180 volts and the separated wires go to the points so when the points close it fires the coil.
 

carstetj

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Re: 70 Mercury 200 20 hp no spark.

Ok, I got some things to check tomorrow I'll let you all know how it goes. I appreciate all the help.
 

satanclause

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Re: 70 Mercury 200 20 hp no spark.

It is not wierd, i first posted the "First Line as you said" then i thought i could clarify this further and went in and edited my post. It's like when Saddam went to the shrink and he Said. Good news Mr Saddam your not paranoid, "The entire world acually wants to kill you" :p
 
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