87 searay - 3.0 Merc. NO SPARK ??

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dacompdoc

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3.0 litre mercruiser (181 cid) NEW Battery, coil, points, cap, rotor, condensor, plugs & wires, ran awsome last year. stored it over winter and most of summer. Engine Turns over, fuel is pumping, carb is fine. I have a fluke multimeter, there is power comming into the coil, power under the cap, but it will not produce spark or current from the coil for that matter. If anyone can help or has had similar issues please respond. I want to get it on the water for the holiday weekend instead of having it at a shop paying hundreds of dollars. Thanx
 
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dacompdoc

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Re: 87 searay - 3.0 Merc. NO SPARK ??

yea the points were set great, the engined purred like a kitten last year .. im not getting anything out of the coil .. i even stuck a screwdriver in the end of the plug comming from the coil and held it close to the engine block, and no arc .. nothing. i even held onto the wire and didnt even get a tickle. .. ? but the coil has power and is brand new. the previous coil did the same thing, thats why i changed it out, i thought it was bad .. but it still does the same thing.
 
wire2

wire2

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Re: 87 searay - 3.0 Merc. NO SPARK ??

Put your Fluke on the primary posts of the coil, key on, dist cap off, points closed. Should see ~4-9 volts. Now open the points with a small screwdriver (in a way that you don't short them together.) There should be a small arc between the points (indicating that a DC current was interrupted), the Fluke should show zero and there *should* be a spark from the coil secondary lead across a ?" gap to engine ground.
 
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dingdongs

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Re: 87 searay - 3.0 Merc. NO SPARK ??

last year isn't now.are the points opening and closing.remove cap and check,may need an assistant.
 
Don S

Don S

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Re: 87 searay - 3.0 Merc. NO SPARK ??

If the engine sat for a long time and now has no spark, chances are the points are glazed over and while making physical contact, may not be makeing electrical contact due to the corrosion. To test, file the points (Both sides with a points file) and see if you get spark then. You need to replace points after filing, as it's only good for testing, not continuous use.
 
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dacompdoc

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Re: 87 searay - 3.0 Merc. NO SPARK ??

ok, well i tried the voltage test and it worked just like u said, it sparked then showed zero volts, and ive also filed the points because they did have corrosion, but they do open and close, so thats working, but im not getting any output from the coil to the dist. ive stuck a screwdriver in the coil wire going to the dist. and held it to the engine block or the lift hook, and i get no spark from it. its like the coil is dead, but its brand new and i have voltage everywhere ... this is a very strange problem. ive had 3 people over to look at it and no one can figure can it out. theyve all said " it should be working " ???
 
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airshot

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Re: 87 searay - 3.0 Merc. NO SPARK ??

check shift interupt switch to see if bad and or stuck as it does ground out the coil, trying running a hot 12v wire to the pos side of coil and see if you get spark. Just went thru a similiar issue myself, dirty/loose connections and adjustment to shift switch ended the problem.

Airshot
 
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dacompdoc

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Re: 87 searay - 3.0 Merc. NO SPARK ??

yes that neutral switch was exactly what i was thinking about ... its dark out now, so after work tomarrow im gonna bypass the switch. i have a quicksilver commander throttle unit. ill bypass that and see what happens .. ill let everyone know. anymore ideas im open for them ..? thanx everyone !!
 
wire2

wire2

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Re: 87 searay - 3.0 Merc. NO SPARK ??

dacompdoc said:
ok, well i tried the voltage test and it worked just like u said, it sparked then showed zero volts, ....
Click to expand...
Ok, if you saw a small arc at the points, and you saw voltage with the Fluke you have current into the primary of the coil.
Next test is see if the secondary winding is open. Key off, Fluke on Ohms x 100 or 1000, check between either + or - post and the hi voltage tower connection. If it reads infinity, the winding is open. Replace coil.
If it reads *some* resistance, next check the condenser. Remove the condenser lead from the points, put the Fluke on Ohms R x 100, Put the leads on the open wire and the case. The meter should roll a value down as it charges. Reverse the leads, test again, should be a high reading, then rolling down.
 
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dacompdoc

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Re: 87 searay - 3.0 Merc. NO SPARK ??

Well I got it running !!! it turns out the "NEW" Condenser i bought was faulty. I put my old one in and it fired right up. Thanks for all the ideas everyone .. appreciate it !!
 
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