BoatBanter.com - View Single Post - stuck outboard flywheel removal info sought!!!!!!!

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On Sun, 10 Dec 2017 14:16:55 -0500, John H
wrote:

On Sun, 10 Dec 2017 14:01:22 -0500, wrote:

On Sun, 10 Dec 2017 11:17:02 -0500, John H
wrote:

On Sun, 10 Dec 2017 07:00:28 -0800 (PST), wrote:

On Tuesday, 6 May 1997 08:00:00 UTC+1, wrote:
?Help, my force 85 hp needs the flywheel removed and the things stuck fast, penetrant
oil is useless. How much if any heat can be applied where to get it loose? Its only been
on two years and was installed with neversieze so it shouldnt be such a pain.
Thanks in advance
tom.

Loosen the flyweel nut and apply WD40 (or similar) to shaft - leave overnight. Use a correct puller (make or buy) threaded into the (usually) three holes in the flywheel. With the centre bolt torqued up with as much as you can muster with a typical standard length socket wrench and holding the flywheel with a strap wrench to stop rotation, hit the centre bolt to jar the taper free. May need several blows, but don't overdo it! I would consider that heat is the last resort, as the risk of damage is high. By the way, heating the flywheel enlarges the centre hole because the whole flywheel becomes slightly larger, including the centre hole.

You'd think that after 20 years the WD40 may have loosened it up. Personally, I'd go for PB B'laster
instead of WD40.

WD40 is great for what it was designed for (Water Displacement) but a
poor substitute for a lot of things people use it for.
It really doesn't matter much on these flywheels tho. That is 2 finely
machined parts pressed together with thousands of pounds of force.
(75-85 ft/lbs times the mechanical advantage of a fine thread screw)
The joint is pretty much air tight and a liquid solvent is not getting
in there. Heat is the real answer but you don't need a lot of heat to
break that bond if it is applied properly and you have a little
patience. The puller on, overnight, always seems to work for me. I
think it may just be the cool night air followed by sunrise heating up
the flywheel or something. They always seem to be loose by the time I
get up ;-)

I've always had pretty good luck with PB Blaster, but agree that a bit of heat has it's uses.

Blaster works on threads because they are not really that a tight a
fit and it penetrates the corrosion in the gap. The flywheel is a
tapered surface matching another tapered surface. A gas valve works
the same way and it is gas tight even under moderate spring pressure.
When you put a nut on that and torque it down they are almost friction
welded together.
Most of the help I see with blaster is really after it starts to move
anyway. It keeps you from galling up your new found freedom and allows
you to keep going.