I cant remove the flywheel, on a 125

[tommarvin]

Hello, I have been trying to remove the flywheel on and off for a few weeks now, PB blaster, breaker bar, finally striped a bolt, installed a heli coil, just tried a HF electric impact wrench, no luck.
Nothing is broken, should I just leave it alone, until something in there breaks ?
I'm a construction handyman I can fix anything in one day, My fear is everything takes a week,or weeks to fix on a boat, My point, I don't want to be broken down for one day longer than I have too, during our priceless summer boating season. Your thoughts please. Thanks

 

[Jiggz]

Removing the flywheel is not an easy task unless you have removed it before or at least done it before. As for the stripped bolt holes instead of using helicoil, drill them to next larger bolt size which I believe is 5/16". Use the three point harmonic balancer puller, apply a lot of torque force without breaking any bolt. Then using a propane torch heat up the center of the flywheel. It needs to have a large amount of heat so you can expand the flywheel before the crank. DO NOT USE HEAT GUN for it will not help at all. While heating it up with one hand, use the other hand to hit the center post with a 5 lb sledge hammer or any large heavy hammer. I mean hit it hard until you hear a pop. Then you can stop the heat and quickly turn the center post to pull the flywheel out all the way.

 

[racerone]

Facts---An outboard flywheel is positioned with a key to get proper spark timing.-----------The flywheel is driven by the locking tapers of the crank and flywheel.-----When the flywheel nut is torqued the flywheel is stretched over the crank taper, yes it is.--------So install the proper puller and tighten the center bolt as much as you dare.-----Then give the center bolt a good rap with a hefty hammer.--That should get it removed.---------Penetrating oils and potions are not needed at all.

 

[fmt2bx]

No Title

Hello, I have been trying to remove the flywheel on and off for a few weeks now, PB blaster, breaker bar, finally striped a bolt, installed a heli coil, just tried a HF electric impact wrench, no luck.
Nothing is broken, should I just leave it alone, until something in there breaks ?
I'm a construction handyman I can fix anything in one day, My fear is everything takes a week,or weeks to fix on a boat, My point, I don't want to be broken down for one day longer than I have too, during our priceless summer boating season. Your thoughts please. Thanks

tommarvin, I feel your pain.
I was there this last summer and it seemed like it wouldn't come off.

This is what I used (got it at napa), with a small piece of wood and a hammer, a small tap from under the flywheel and the whole thing literally flew off!!!
If you try, I would suggest you unscrew the flywheel bolt 1/4 inch or so and leave it in place. This way the flywheel won't fly off.

Hope this help.
Take care

 

[flyingscott]

Do not hit the flywheel you can crack or chip it do what was suggested in post #3

 

[SkiDad]

i used the same puller as fmt2bx and it worked great - hit it with a 2 lb sledge pretty hard and then kept tightening and hitting the center bolt till it popped - took only a few minutes. I remember not knowing what would happen but it worked out.

 

[Frank Acampora]

Sometimes the flywheel will "cold weld" to the crankshaft nose. Then it can be a real female dog to remove. What happens is that the flywheel hub and crankshaft are what is known as a "locking taper" The key locates the flywheel for proper timing and the taper locks it in place. However, this is dependent upon using the correct torque value on the nut (95 foot pounds).

Sometimes a little water does work its way into the keyway and taper and a bit of rust forms, cold welding the parts together. This makes them very difficult to get apart but not impossible. Use a heavy duty puller and a heavy hammer. You can also wedge a prybar under the flywheel at the rear between it and the block. Just be careful not to damage the magnetic strip.

Some heat and banging and eventuaklly you will get it off. You may need to sweat a bit though.

As long as it is not a Mercury flywheel and ignition, there are no components under that flywheel to be damaged so you can drill the three holes in the top all the way through and tap them. This will give you full thread engagement for maximum pulling power without stripping. You can re-tap to 5/16-18 for better thread strength.

 

[tommarvin]

A big THANK YOU to everybody that replied, with all your kind help, the flywheel is now removed.

If anybody is ever out this way, Puget Sound Washington State, I will show you around in the boat, summer crabbing is July 1 - Sept !

 

[jerryjerry05]

Good that it came off!!
​Why take it off?

I had one that "cold welded" itself and did NOT come off.
Turns out the block was scrap anyway but I spent a day trying to get it loose.
A torch and a big 3 jaw puller and lots more.
Never did get it apart.
Hmmmm crabs, July 3000 mi. I'll just crab here. No season here. Open all year.

 

[tommarvin]

I'm trying to be proactive and learn as much as I can, so when something breaks inside our 125, we { me-myself -and I } can fix it ASAP.

When we bought the boat I knew nothing, with the help of everybody in this forum, I can now rebuild the motor fast when it breaks, I know which machine shop, pistons, wrist pins,, etc. Its a really good feeling, not being at the mercy of our 125.