1979 Mariner 9.9 Flywheel

[Bullie]

I am not making any progress pulling the flywheel on this 79 9.9 Mariner (Yamaha). It appears to be in several pieces rather than a solid cast flywheel. Is there a secret to pulling these things or should I continue how I would to pulling a Evinrude/Johnson or Mercury flywheel. This motor does have three threaded holes that are spaced for a puller. I put my puller on it and put on some pressure on it but it hasn't popped yet.

 

[flyingscott]

Use your puller that has the 3 bolts get it as tight as you possibly can. Give the top of the puller bolt a good smack with a carpenters hammer may need to hit it more than once. If it Doesn't come more tightening and hitting eventually it will pop.

 

[gm280]

Oh yes the stubborn flywheel issue. Basically OB flywheels are very hard to remove. And that is because of the tapered crankshaft fitted to the equally tapered flywheel. So you have to torque the bolt to the max (using grade eight bolts) and then torque some more. And I can tell you once it does let loose, you will hear it and think it broke. But that is just the flywheel letting go. A loud cracking sound is success. Stay with it, it will pop off soon.

 

[GA_Boater]

And don't take the nut off. Just loosen it enough with a gap between the the nut and flywheel so when it does pop, the flywheel and puller don't go flying off into the corner.

 

[Bullie]

Thanks guys! Lately I haven't had too much trouble with flywheels, this one just made me back off and ask first. This old Mariner/Yamaha flywheel is made very differently than the OMCs I usually tinker with as it seems to be made of a couple different metals and has the lobe, to open the points, machined into the base of the flywheel. I figured best to ask if there was a different technique to these.

I had been hitting my puller with a soft mallet when the normal impact driver didn't pop it off. I then followed flyingscott's advice and whacked it with a bigger hammer. Popped off on the second try. And, now I have metric bolts should the need arise again.

The points were the problem. All polished up, cleaned with acetone, and she was popping when i turned the flywheel by hand. The spark will jump at least 1/2 inch now. Cleaned dirt dauber residue out of the carb and she is ready to take my dad and his buddy fishing again.

Thanks again.

 

[gm280]

Thanks guys! Lately I haven't had too much trouble with flywheels, this one just made me back off and ask first. This old Mariner/Yamaha flywheel is made very differently than the OMCs I usually tinker with as it seems to be made of a couple different metals and has the lobe, to open the points, machined into the base of the flywheel. I figured best to ask if there was a different technique to these.

I had been hitting my puller with a soft mallet when the normal impact driver didn't pop it off. I then followed flyingscott's advice and whacked it with a bigger hammer. Popped off on the second try. And, now I have metric bolts should the need arise again.

The points were the problem. All polished up, cleaned with acetone, and she was popping when i turned the flywheel by hand. The spark will jump at least 1/2 inch now. Cleaned dirt dauber residue out of the carb and she is ready to take my dad and his buddy fishing again.

Thanks again.

HA Bullie, that is great news. Some times it take a little more persuasion and a good whack with a hammer will do it. :thumb: