I have had excellent luck using a harmonic balancer puller. You can buy them at most auto parts stores complete with bolts for pulling. Although I had to buy some different ones for my flywheels. Always buy hardened bolts.
I bought mine from Harbor Freight for $10. I wouldn't recommend it for heavy use, but it has served me well for several flywheel pulls.
"http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=37824"
Important note: Take care in threading the bolts into the flywheel. I don't know the precise measurement, but if you go over about 1/2" into the flywheel you are likely to hit and destroy a coil. A good manual should give you the length of thread.
If there's any question about how deep to thread the bolts in the flywheel, bend a small right angle in a stiff wire, like a paper clip. Insert the wire into the flywheel bolt holes and use the right angle to "hook" the bottom of the threads. Mark the wire or put a piece of tape on it even with the surface of the flywheel. Withdraw the wire, and it will indicate how deep the threads are.
Some harmonic balancer pullers are way too cheap....in construction. Don't waste your money on one of the flimsy aluminum ones. Use only Grade-8 bolts and screw them in 7/16", no more and no less. Then give it heck. You have to tighten the daylights out of the puller bolt before it pops off, but it WILL pop off. No penetrating oil or heat needed or advised.
Very IMPORTANT: When you put the flywheel back on, the flywheel and shaft tapers must be perfectly clean and dry and you must use a torque wrench to tighten the nut to 40-45 ft/lbs. Ignore this and you will ruin your flywheel and crankshaft.
Some auto parts stores have these tools to loan or rent.
RetNav: Try that impact without the proper hold down bolts. You have been removing very small flywheels. Try one torgued down to 105 lbs, or better yet, one lapped, loc-tited, and torgued to 120 lbs.
I use nothing but the OMC puller that I bought from my local dealer. Since it is made for the motors, it comes with hardened bolts of several different sizes and works very well. I agree with the use of an impact driver - I use one to both loosen the crankshaft nut and to drive the puller.
I use a harmonic balancer remover too. Knowing how to use one is more critical than which one it is. Bolt depth has already been mentioned. The puller works best with the center bolt aligned perfectly straight and with the same torque on the three outer bolts. On tough flywheels I use a small in lb torque wrench to dial in the outer bolts for equal pulling. It's a better alternative than whacking hard with a mallet first. It makes the difference between the flywheel popping off harsly or gently.
