No spark to a Merc 7.5 horse.

[chromepursuit]

I have an older 7.5 Merc and not getting any spark from the plugs.. Anybody thinks its the plugs or something else? It's a two stroke with twin cylinders..Had it running just fine the other day, now..No spark.

Thanks

[Boat Doc']

Check the stop switch, it may be stuck. You can check it by unpluuging the wires. Note; If it starts you can't shut it off without plugging the wires in.

[chromepursuit]

Thanks...I'll try it

[jparke8]

I had one of those the electronic module went bad had to buy another cost $200.00. What model is your, this one had a blue stripe on it. I think it was a early 70's model. it also had coild one you can check this with a ohm meter

[chovy]

I have a 1972 7.5 merc. The coils (one for each cyl) eventually fail. I have replaced both of mine. I bought one from Clemons a few years ago. I think I paid $ 50 for one (ouch!). You can test the coils by hooking up a voltmeter to the coils and pulling the starter cord. If you don't register any voltage the coil is probably bad. Clemons can probably test the coils for you if you don't have a voltmeter.


Jeff

[Mailman54]

What year? I have a 1972 9.8 Merc basically the same motor as the 7.5, but Merc changed the ignitions alot back then between the different years, had the same problem...no spark. finally chased it down. Get a manual, check the condenser under the flywheel, while your in there check the insulator blocks on the points...they crack and will short to ground, if yours has the module...they can be found for around $100 shipped out of new york. Hope this helps.

Mailman54

[ForeverFishing]

I have a similar Merc, although 9.8 hp. It's probably the module, especially if both plugs don't spark. Mine went out and had to be replaced.