Help with Johnson F70 flywheel

[ERROL STILLINGS]

Having difficulty pulling the flywheel off the driveshaft using a harmonic balancer.
To start with, the ropestart on top of the flywheel has 4 screws instead of the usual 3
in the newer Johnsons. The harmonic balancer is also set up for 3, and with larger
bolts. I’m afraid the flywheel comes off a different way because I have put quite a bit
of pressure on the two smaller bolts I can line up with the harmonic balancer and have
had no result. How does one remove a flywheel from an F70 Johnson?

[david-bartlett]

Itchy,

I would try a different style puller. Probably would try making one from a piece of steel plate, with holes drilled for the pulling bolts, and a nut welded on for the thrust bolt. Don’t force that flywheel. Not many of those around.

[Mumbles]

I wouldn’t use any kind of a puller with those four holes as they are threaded 10-24 for the sheave screws and the screws used with a puller might break off opening up another can of worms. Here’s where a flywheel knocker comes in handy or else run the flywheel nut up flush with the threads on the crankshaft and give it a good sharp blow with a hammer while lifting the motor by the flywheel at the same time. The motors weight has to be supported by the flywheel or it can be damaged inside. This is how I remove the flywheel on my F-70 and it works every time.

I can’t find a pic of or link to a thread on making a knocker out of two nuts and a bolt with the same threads as the crank has. It’s real easy to make and maybe someone else can help. FR?

[david-bartlett]

Good catch Mumbles regarding the screw size. I forgot about those 10-24 almost impossible to find screws.

[Mumbles]

They’re just oval head screws but it sure wouldn’t take much to break one off! 😀

[david-bartlett]

Flywheel knocker.

http://www.marineengine.com/boat-forum/ … 1376417864

[Mumbles]

That’s the one!

[ERROL STILLINGS]

Thank you very much. Glad I quit when I did with my harmonic balancer – will work at the knocker!

[Tubs]

itchy
Sent you a PM

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[ERROL STILLINGS]

Thank you guys very much. I made the flywheel knocker – supported the outside edge of the flywheel so the weight of the
motor was on the crankshaft – gave about three sharp pops on the knocker, and got the flywheel off. Wow! I’m happy.
Thanks you guys.

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