Flywheel Re-usable? Need help!

[70XIN]

Hey guys, you might have seen on my last thread here:
http://www.toymods.net/forums/showthread.php?t=52962

We got the flywheel and crank back today from the machinist (gave it a run on the lathe to tidy it back up), the crank seems like it will be 100% fine, but im not so sure about the flywheel, basically there are no raised areas on it anymore, but as you can see theres still plenty of craters! ill let the pics do the talking.

What are your thoughts? can we re-use this, engine machinist said yes, we are not so sure.





Thanks guys
Seamus.

[Hurricane]

im thinkin yes, it seems to still have lots of flat area to hold it square on the crank, as long as the flywheel sits on the step out on the back of the crank ok, i would be happy to reuse it.

or how hard is it to get another flywheel? then u can be sure it will be ok then.

dan.

[Tweak]

Id ditch it. You have lost mass from the fly wheel. Its a uneven loss and will cause a vibration.
Maybe not at low revs but come 5000 to 7500rpm your gonna feel it for sure

[pandaah]

aslong as that flywheel mounts flat on the crank flange, as to say the pitted areas dont cause highspots when mounted, and you use NEW bolts and LOTS of loctite.... that would be fine

[thechuckster]

actually - using lots of loctite will result in another failure. Use a small drop or three on the thread only, none under the head of the bolt and none at the tip of the threaded section. Loctite works in the threaded areas only and too much will stop it bonding/curing.

personally, i'd try to find another flywheel.

[pandaah]

i dont mean like pour it on, i usually try to make sure most of the thread has got loctite running through it cos as you wipe off the excess its only the loctite that remains in the thread...

[RobertoX]

You're using a 4ac flywheel right? Usually they are free (with a motor attached)... I wouldn't have even bothered to pay to get it machined in the first place!

For $0 (or maybe $20 if unlucky), no matter how small the uncertainty, a new one is cheap insurance!

[kaido]

id ditch it... after seeing pictures of what happens when a flywheel lets go.... i wouldnt risk using a damaged flywheel....that is if you like having legs.

[mattysshop]

i'm actually surprised that crank isn't knife edged!

[Hurricane]

Id ditch it. You have lost mass from the fly wheel. Its a uneven loss and will cause a vibration.
Maybe not at low revs but come 5000 to 7500rpm your gonna feel it for sure

i would have thought that the mass loss inside the crank width area wouldn't change any thing? only outside that area would make a difference?


going off what others have said if a new flywheel is cheap or free, run with a new one for sure.

dan.

[Smokey228]

I would re-use it. As i dont see it causing ot much problem, as its on the mounting face. Its been machined flat so its not going to have any inconsistencies, and its a 4ac. They only see 5-5500rpm every few weeks...

But for what its worth, im dodgy as fuck and you should replaec it if care for the car...

Cheers,
Jase

[legend]

if it was a steel flywheel i would use it but cast is prone to cracking when damaged
if u can get another flywheel u would be better off or u can get them repaired and machined but cost comes into that
good luck

[allencr]

Is this flywheel one of a kind, something rare & expensive? There's nothing stronger then cast iron when being compressed, but when being expanded at 7Krpm, its brittleness doesn't get helped by having a ready place to start F'ng up in a piece that has already been under some abnormal stress.
I'm really more interested in how it got that way.
Pics of the bolts?
Like welded in just a few spots with the areas next to it being almost untouched.

[the_random_hero]

I would re-use it. As i dont see it causing ot much problem, as its on the mounting face. Its been machined flat so its not going to have any inconsistencies, and its a 4ac. They only see 5-5500rpm every few weeks...

But for what its worth, im dodgy as fuck and you should replaec it if care for the car...

Cheers,
Jase

It's not a 4AC by any means.

[ddeane]

Gidday
I am the cautious kind. I would not consider reusing a flywheel that has taken that type of beating. Being cast it would be more prone to break apart than steel and the thought that the damage it could do to me, let alone my car, is scary.

Cheers Craig