I Got Me a Mercury !!!

tpenfield

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The new(er) (blue label) Merc is not feeling well today. I was going out to the big boat, but the Merc 7.5 had other things in mind. I think the ignition is intermittent. I'll have to do some more testing to see for sure. I tried starting fluid, new spark plugs, but nothing. Last time out must have been a fluke.

While the Blue Merc is being diagnosed, I'm thinking of picking up a 2 cylinder 4 (ish) HP JohnnyRude engine. My other motor . . . the little 3 HP Yammy really does not run all that well and it has its own set of starting issues. It is a one cylinder, and does not idle well. I think single cylinder engines are not meant to idle down low, unless they have sizable flywheels. I've noticed that with outdoor power equipment . . .1,200 RPM idle is about all you can get.

Meanwhile the toolbox will be open for the Blue Merc. . .
 

racerone

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A 6 HP Johnson / Evinrude from 1966 to 1979 are ideal.----The 66 to 76 used the universal ( low cost ) magneto.-----Need to know how to clean breaker points on occasion.----The 77 to 79 had electronic ignition.-----These are just wonderful motors if in good condition.
 

tpenfield

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I have a 4.5 HP Johnson from the 1980's (maybe 1984) . . . but it is a long shaft. It was a bit finicky when I first got it, but now it runs pretty well.

Maybe find its short shaft cousin.

My plan is to go through the Blue Merc's ignition system, test the coils, replace wires, etc. It would be nice it I could have it as my go-to motor for a while.
 

tpenfield

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My game plan for the Blue Merc is to pop the flywheel off and go through the ignition stator wiring, replacing sections of wire as needed. Since the motor actually worked for me on several occasions, I am thinking that the problem may be with connections vs. bad coils.
 

tpenfield

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I'm on my way to CA and will be there for 2 weeks. Plenty of time to read up on 'Phase Maker' ignition systems, which I believe is what Mercury has in these early-1970's motors. :unsure:
 
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