Slightly damaged Flywheel... Do I need to replace it?

[pjbrownva]

Motor: 1998 Mariner 150 HP V6...

Being a back-yard mechanic, I tried to improvise to remove my fly wheel, and I ended up completely stripping several of the threads off the the center of the fly wheel itself -- my homemade solution ended up woking more like a lathe, and completely removed the first three or four turns of the thread on the inside of the fly wheel, plus it cross-threaded the threads that remain.. :facepalm: :facepalm: :facepalm:

I then used a crow bar... plus about 1 or 2 hrs time -- to GENTLY pry the fly wheel off the motor, using the stator and the motor block for bracing and leverage (replaced the stator anyway... so didn't care about damaging it)... Although I don't believe that the prying damaged the fly wheel at all.

So here's my question...

Do I need to replace the fly wheel? I know it acts as a harmonic balancer, but I don't know just how sensitive the balancing is. Between the prying (I don't think that caused damage), and (more importantly) stripping and accidentally totally removing the first 3-4 turns of the thread in the center of the fly wheel, I have obviously made very small changes to the balance and/or center of mass of the fly wheel.

Is this enough of a change to cause concern and warrant me replacing the fly wheel. While I'm not anxious to waste money, I'd rather replace the part now if I should ($200 on ebay)... than be "cheap" and end up causing severe engine damage down the road.

Thanks, everyone! I love the help that this community provides.

P.S. -- A heavy duty crow's foot, universal fly wheel puller is on the way to remove this "damaged" flywheel if/when necessary in the future, and I WILL order the correct fly wheel puller if I end up replacing this fly wheel.

 

[pjbrownva]

Re: Slightly damaged Flywheel... Do I need to replace it?

Motor: 1998 Mariner 150 HP V6...
I then used a crow bar... plus about 1 or 2 hrs time -- to GENTLY pry the fly wheel off the motor, using the stator and the motor block for bracing and leverage... Although I don't believe that the prying damaged the fly wheel at all.

(Do you feel lucky, punk? http://www.youtube.com/watch?v=8Xjr2hnOHiM )

 

[Bob_VT]

Re: Slightly damaged Flywheel... Do I need to replace it?

The first words that come to my mind......oh never mind....:facepalm:

If the damage is in the center and you feel secure with the threads remaining that is okay. The further away from the center the worse off you would be.

Can it be re-installed tight?

Is it still true and flat?

It is totally your choice to evaluate and if it will work........ make sure it will tightly and completely attach. I imagine a metal frisbee taking off at 5500 rpms would be dramatic !

Would I look for a replacement.......uh yes if one came along at a reasonable price.

 

[pjbrownva]

Re: Slightly damaged Flywheel... Do I need to replace it?

Thanks for the reply Bob_VT. The flywheel is flat, and it will secure just fine. The damage was to the threads on the flywheel where
the fly wheel puller attaches, not to the retaining nut or the part that the retaining nut bolts to.

Is there a way for me to check whether or not the fly wheel is off balance? It's really a small amount of metal that was removed (and from the center like you said Bob_VT... But I just don't know how delicate the balance is and whether or not this could cause a negative impact.

With that said, right now I'm leaning towards getting a replacement on ebay and using the current fly wheel until the replacement arrives... but I guess I haven't made a final decision yet.

 

[Chris1956]

Re: Slightly damaged Flywheel... Do I need to replace it?

Those threads are simply for installing the lifting eye or flywheel puller. I would not worry about it. Just do not use a lifting eye.

Write yourself a note on the flywheel, so you don't forget.

 

[jimmbo]

Re: Slightly damaged Flywheel... Do I need to replace it?

The issue isn't the damaged threads for the puller. That this style of Flywheel(flex plate) was pried off should be of concern. The top is basicly a piece of sheetmetal attached by bolts to the hub and the outer magnet ring resulting in. Prying on the magnet rig could result in the top being stressed in ways it wasn't designed for. As Bob-VT said it could become a 5500 rpm metal frisbee. I myself wouldn't use it. But as mentioned before it is your choice. It could also be your liability if something should go wrong

 

[Chris1956]

Re: Slightly damaged Flywheel... Do I need to replace it?

It is a piece of stamped steel, not a casting. It is not going to crack. If it is not bent, I would think it is fine...