Re: 1966 Merc 95hp Backfiring Help
About the only correct way to pull the entire flywheel without a puller is to remove (2) opposite bolts on the center hub (they should be 5/16-NF, if they're 1/4" you may have trouble getting them out without breakage), then use Grade 8 bolts with an automotive harmonic balancer puller. I did it this way for many years before I got a >proper< puller !
If you have access to a big strap wrench you can use that to hold the flywheel. Or wrap a length of rope around the O.D. of the flywheel, using a breaker bar or other suitable instrument wrapped up in the rope, such that you have a Pore Man's strap wrench. This'll do in a pinch. Another (last resort) method is to clamp a stout pair of Vice Grips to the rim of the starter teeth, such that the pliers angle downwards so you can spin the flywheel around and use the upper rear cowling mount as a backstop for the pliers. This works better if you clamp 2 sets of pliers on the rim. Take care not to gouge the rim if you do this.
If you have an air impact wrench, likely you won't even have to use anything but a gloved hand to hold onto the flywheel. Typically if you use the air tool, you put upwards tension on the puller with one hand, air tool in the other, and she pops right off.
Of course, nothing substitutes for having the correct tool ! And the one from the Merc dlr isn't that expensive. There are also "lesser quality" pullers on eBay for considerably less, that'll still do the job. Just don't plan on pulling flywheels every day with one of them 'cause they won't last!
There's one last method, remove all the bolts holding the flywheel "flex plate" to the center hub. If you do this, be Very Very sure to make obvious match marks so you can get the flywheel back in the same exact position. Best to line up the motor so #1 cyl is at TDC with the belt timing marks on dist and flywheel lined up, then make sure not to turn anything as you're working on it. Even with the center hub in place, you can remove the stator and replace the belt.
Something to watch for when you tear into it: check the belt drive sprocket on the flywheel for cracks. I had an older motor with a cracked sprocket and the darn thing would rotate, changing the timing constantly. Drove me crazy until I figured it out! In that case, you'd have no choice but to remove the center hub but if you had the flywheel off, you could even use a jaws-type puller on it.
BTW if you pull the flywheel hub center bolts, put a drop of Red Loctite on each bolt and torque to approx 25 ft-lb upon reassembly. Torque spec for 1/4-20 Grade 8 bolts would be a bit less, Google on "SAE Torque Specs" to find that out.
HTH...........ed
