Mercury Mark 55 Help

[texastinker]

I am just needing someone that I could ask questions to as I start going through this motor. There is plenty of information available for OMC engines, but not as much for the Mercurys. I was going to sell this motor, but the more I look at it the more I want to get it running. Currently I have no spark and I do not know how to work on this type of magneto. Aslo will the wiring harness on the front of the motor keep the mag from giving spark?

[jeff-register]

There is a insulated bolt on the distributer that shuts it off. If you have no spark remove the distributer & clean & reset the points. It hangs upside down & the bearing may be leaking oil on the points.

[jw-in-dixie]

I hope you do get it running. There’s nothing like the old Merc fours. They run great.

I find it is easier to work on the magneto if the motor is set on its head. Then you
can see a lot better. It should have a Fairbanks-Morse magneto, point setting .010 +.000, -.002, ie a tight .010. Plugs should be Champion J6J set @ .025, or better Jap B6S, IMHO.

Jeff knows all about these motors.

Good luck, JW in Dixie

[dave-bernard]

call me if you need help
1 914 310 7086
Dave.

[jeff-register]

Thanks J.W,
I believe Dave & J.W. know more than me. My last 4 cylinder motor came from J.W.
Thanks so much!!

[jw-in-dixie]

RE: "My last 4 cylinder motor came from J.W."

But I had not run it. SO, have you run it?

Best regards, JW

[texastinker]

Well I pulled the magneto and found it to be very dirty. Pretty sure the coil is good because it shocked me when I spun the splines by hand (accident). I dressed the points and set them with a multi meter because I am not good enough to do it by hand at.010. The mag cover is cracked so I will need another one of those. I put it together and checked spark and it fire a blur spark 7/16". Squirted a little fuel in the carb and she fired and ran on the first pull for about 5 seconds.

Now I need to figure out how to get the prop off. The lower unit is frozen and I cant get the prop off after I take off the nut and the tab washer. Is there a secret. I used lots of PB Blaster and some heat and light prying. No go. Is it easier to find a different lower unit if I can get the prop off of this one?

[dave-bernard]

call me about the prop and lower. 1 914 310 7086.

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