I am stumped how to test my motor

[iggyw1]

I have worked on a few outboards in my days and got them all going. I am mechanically inclined, but I am stumped now. I have a Mercury 1964 model year. 3.9 H.P. ( model "39")? Serial number is 1698008. I have just rebuilt the carburetor and fuel pump diaphragm, new float and needle valve. It started good last week when I was done. now it is flooding out when I try to start it. I want to check my spark and other things, but, the recoil rope is up inside the top of the motor cover. How can I possibly crank this motor without the lid off? Is this possible? How would I even check to see if I am getting a spark if I cannot turn the motor over without the top on it and then I cannot see anything inside. There is no emergency flywheel inside that some motors have where you could put a rope on it and pull it off. Any help would really be appreciated. Thank you!

 

[alldodge]

I have worked on a few outboards in my days and got them all going. I am mechanically inclined, but I am stumped now. I have a Mercury 1964 model year. 3.9 H.P. ( model "39")? Serial number is 1698008. I have just rebuilt the carburetor and fuel pump diaphragm, new float and needle valve. It started good last week when I was done. now it is flooding out when I try to start it. I want to check my spark and other things, but, the recoil rope is up inside the top of the motor cover. How can I possibly crank this motor without the lid off? Is this possible? How would I even check to see if I am getting a spark if I cannot turn the motor over without the top on it and then I cannot see anything inside. There is no emergency flywheel inside that some motors have where you could put a rope on it and pull it off. Any help would really be appreciated. Thank you!

No expert here but many can have the recoil mech removed from the housing and installed temp on the shaft

 

[racerone]

No that won't work at all !!!---------I am sure dealers at the time had a cowling that was cut away to make adjustment on the motor.-------Or they installed a pulley to use a rope.------Or carefully lift the cowling off after motor starts to do inspection / adjustments

 

[merc850]

If this is your type of flywheel you use a cord with a knot on one end and a handle on the other, put knot in hole (green hilite) and wrap/pull it in the direction of arrow.

 

[iggyw1]

If this is your type of flywheel you use a cord with a knot on one end and a handle on the other, put knot in hole (green hilite) and wrap/pull it in the direction of arrow.

My flywheel is similar to the one you are showing, however, mine is flat spaces between the "crowns" rather than rounded bottoms, and on mine, they are all the same, flat bottoms and no place for a rope!

 

[iggyw1]

No that won't work at all !!!---------I am sure dealers at the time had a cowling that was cut away to make adjustment on the motor.-------Or they installed a pulley to use a rope.------Or carefully lift the cowling off after motor starts to do inspection / adjustments

You are probably right about the mechanics having some type of fixture. The second part of your reply works only IF I could get the thing running. Last week I removed the cover while it was running and made my adjustments on the carb. The thing ran perfect last week. Now it flooded out trying to start it. Doesn't even sound like its firing now.

 

[iggyw1]

No expert here but many can have the recoil mech removed from the housing and installed temp on the shaft

I looked at that very close, and there is no way possible to do that, but thanks for the suggestion because I never even thought about looking into doing that.

 

[merc850]

Try this site for older Mercs http://johnsoldmercurysite.com/phpBB3/viewforum.php?f=7&sid=0d427613d1e1c1c32a919ff4be6fe5ad

 

[iggyw1]

I am just thinking now about having something welded onto the flywheel to attach a rope that will wrap around and pull off manually, but doesn't the flywheel need to be perfectly balanced? If so, anyone else have any other ideas? Thanks for all of you for your input.

 

[MTboatguy]

any weight added to or taken off the flywheel will throw it out of balance and it would need to be re-balanced by a machine shop, you don't want to run a out of balance engine, they can tear themselves apart real quick. Call your local Mercury dealer and ask them what they do with them, I am sure you are not the only one with this situation and they probably made a specialized tool for that application.