1983 Mariner 25hp.No spark situation.

Chad N

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Jul 18, 2012
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Working on an 83 Mariner 25hp outboard. Replaced the water pump and now have no spark. Stator and trigger coil are good. Tested ignition coils and found the same reading on (+) post as (-) post going to plug lead. Is the coil bad or shorted? The reading I get is within spec. but I'm not quite sure where to go from here. Thank you
 
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Re: 1983 Mariner 25hp.No spark situation.

Do an old fashion test where you pull the spark plug attach the wire to the plug and put the plug on the head to ground and turn motor over to see if u have spark or pull plug wire and put screw driver in plug wire and hold screw driver up close to the plug and see if you get spark. Also does this motor have a switch boxs and how many cylinders
 

minuteman62-64

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Re: 1983 Mariner 25hp.No spark situation.

Do you have the Factory Service Manual? I've got a 1982 30 HP (Japanese made, 30A) which looks to be the same as yours (maybe?).

Based on my manual, for the secondary coils, resistance between the orange or grey lead and ground should be 1.35 - 1.65 ohms. The resistance between the plug lead and ground should be 4160 - 6240 ohms. Both tests are with the magneto lead (orange or grey) disconected for the coil under test.

The above tests are for the Secondary Coils. There is another procedure for the primary coil.
 

ajgraz

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Re: 1983 Mariner 25hp.No spark situation.

Those coils will have the same ohm reading betwen the HT lead and either the + or - primary leads.

Don't see how a no spark condition could be caused by changing a water pump...did you unhook anything on the powerhead? Maybe as simple as a wire did not get hooked back up (or a wire hooked back up improperly)?
 

minuteman62-64

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Re: 1983 Mariner 25hp.No spark situation.

Whoops! I was reading from the section for the magneto ignition. You obviously have the CD System. Disregard all I said.
 

Chad N

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Re: 1983 Mariner 25hp.No spark situation.

It is a two cylinder. I didn't unhook any wires from changing the water pump. It was in storage for 11 years and just got pulled out. Put some oil in the cylinders and turned it over by hand. Started right up but no water pressure. Changed the pump and now there is no spark. It does not have a switch box.
 

minuteman62-64

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Re: 1983 Mariner 25hp.No spark situation.

Seems like if you didn't do anything to the ignition, there shouldn't be any change. Normally dropping the LU wouldn't impact the ignition. Were you able to disconnect the shift shaft using the coupling nut at the mid-point or did you have to disconnect it up at the power head? If you had to disconnect it up at the power head, maybe you accidently disconnected a wire while moving things around?
 

Chad N

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Jul 18, 2012
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Re: 1983 Mariner 25hp.No spark situation.

I disconnected it at the power head. I double checked all the connections and there were none that would be in the way. Everything is connected how it is supposed to be.
 

minuteman62-64

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Re: 1983 Mariner 25hp.No spark situation.

Looking at the schematic, the only other component that looks like it could cause a problem is the CDI unit. Do you have the Service Manual that describes the testing procedure?

Looks like it would be about $150 for a new one.
 

quicktach

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Aug 24, 2012
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394
Re: 1983 Mariner 25hp.No spark situation.

Nice problem ! Pull the flywheel and check the stator and trigger coil...is the stator firmly mounted ? Any oil leaks getting on anything? Is the trigger coil fitting OK in it's holder? Holder moving OK? Check all your grounds ...any melted wires ? Are you mechanically advancing ? Ignition coils - grounded ? Stop circuits working OK ? If everything around the CDI tests OK, by default it's the CDI. Using a good spark tester ? Keep us posted !
 
M

Maxz695

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Re: 1983 Mariner 25hp.No spark situation.

Pull the plugs and keep the plugs 1/4 inch away from ground and check for a bright blue spark. If this is a non tiller or key throttle shifter set up meaning maybe the lanyard got knocked loose after all these years. If this is a throttle type set up unplug the pigtail and then check for spark. Also check all grounds from a battery if not a pull start and every other gorund you can find. Unless the coil died there is something not connecting correctly and due to the amount of time I,m thinking a broke wire or bad ground
 

Chad N

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Jul 18, 2012
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Re: 1983 Mariner 25hp.No spark situation.

Solved the issue. There was a ground behind the CDI that had recently been painted. Somehow when changing the water pump I must have nudged it causing it to loose proper ground. Removed the screw and cleaned it up. Bingo. Now have spark and runs like a dream. Thanks for the help!!!
 

ajgraz

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Re: 1983 Mariner 25hp.No spark situation.

Good to hear you found the issue. Sometimes it's the simple things. Good grounds are good stuff!
 
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