1976 850 mercury weak spark

[Gartrade]

• The spark plug doesn't spark, but if I stick a screwdriver in the plug wire and hold it close to ground I get a little spark. Same on all four cylinders. Any ideas?

 

[12Footer]

Re: 1976 850 mercury weak spark

Welcome to iboats, Gartrade.<br />I would suspect the starter drawing too much current. Try hand-cranking it (if you have rope slots in the flywheel),and see if you have adequate spark that way.<br />Be carefull tho. 15HP and up, can take your wrist off with the compression. So remove the plugs,and ground them well (Don't try to start with the plug wires dangling free, as it can fry the switchbox).

 

[Gartrade]

Re: 1976 850 mercury weak spark

I tried cranking it with the rope and it still had no spark. I also jumped it to add the extra amps from another battery and still didn't work. Still fishing!! I was wondering whether it might be the stator not putting out enough juice and how a person might go about testing it.