So, I'm about 50% through my stage 3 clutch install, I'm lowering the transmission, I see how badly the clutch/pressure plate is fucked up. Then I get to a spot to where I can view the condition of the flywheel.



The biggest crack on the right hand side and does not go from the inside all the way to the outside, and is just deep enough to catch your fingernail on, doesn't feel too severe. There are several tiny little cracks here and there, but they all look like they will machine out pretty easily.

Does that crack look like a few turns on the lathe will take care of it or should I start looking into an aftermarket flywheel? Trying to keep the spendings low.

 

Well i wouldnt trust that at 9000rpm...



There are lots of aftermarket flywheels at really good prices on the forums. Well worth it to simply get another one.




Just my $0.02.


=Ben

 

lathing it wont help. the chances that the crack is only as deep as the amount of material you will remove via lathe, isnt very good..


as apexFD said- just buy a stronger, lighter aftermarket flywheel and save the trouble. if that thing explodes it will cost more in the long run.

best case scenario is it destroys your clutch. you dont want to know the worst case..


ninja edit style! used flywheels arent hard to come by either. just make sure you dont buy a cracked one ...... wink wink.

 

If your keeping costs down, a used flywheel isn't all that expensive. The biggest issue would probably be shipping. I think I had mine resurfaced for about $40. Either way, I'd never use a cracked one.
BTW, your pilot bearing looks like it might be pretty rusty. They're inexpensive and IMO should be changed, along with a few other things, with any clutch job.

 

Thanks for the responses, I will look into an aftermarket one.

The clutch came with a new pilot/throwout bearing so it will all be new, but the one that's in there at the moment doesn't look too bad in person.

 

If you already have the new bearing, no sense using the old one.


That flywheel is still good....for a paper weight/door stop.

 

Take it to a good machine shop and they will be able to tell you if it can be resurfaced.

Except that you can SNAFU you e-shaft if you don't have the right tool. I've had to grind one out when a snap-on puller set fell short. Luckily the shaft was sitting on a work bench, so it wasn't that stressful.

 

You could always weld it and resurface it ........But I would just buy an aftermarket one.

 

i'll sell you mine. it the stock and has 52k miles on it and is in great condition. i really want to get rid of it(one of the many parts cluttering my room).

 

Then he would also need to re-balance it.

I would suggest just buying a used one. Most people can't even give a stock flywheel away so I doubt you'll have a hard time finding a used stock one for cheap.

 

I know you are changing your pilot and throwout bearing, but make sure you change your clutch fork as well (if you don't have the reinforced one from Mazda). An aftermarket clutch/pressure plate may have some adverse affects on your clutch fork. I speak from experience on this, as I did an ACT clutch install and changed all of the parts except the clutch fork. Guess what part I broke later on?

Just my $.02

 

Why would it need to be balanced? You're taking off the same amount of material at every point on the surface. The flywheel would end up having slightly less mass overall, but the counterweight on the back side of it would not lose any mass.

 

If you weld the cracks you could alter the balance, irregardless of the resurfacing.

 

is that pilot bearing in there stock? it looks like its not set in far enough, plus its missing the grease seal. Thats the position i found mine in when i took the trans off after the bearing siezed itself to the trans input shaft

 

I'll take your word for it.

It's not something I'd think of as a good idea anyways. I would either get it cut at the shop if possible or put it in the scrap metal pile.

 

And you would still need it balanced.....

 

Why? An decent, intact FW, properly resurfaced should be fine.

 

So ANY flywheel you purchase (used or new) you are going to re-balance it? Let's not go overboard here....

 

Oh no no, that IS my point.....

 

Simply buy a used flywheel is completely different than welding on a possibly damaged one.

 

How do i know if i have a reinforced one? Did they come standard on certain years or models?

 

shouldnt you always have a heavier flywheel with Rotaries because of the lack of torque?

 

Never, ever, do this. Replace the flywheel. People who suggest otherwise have no experience in metallurgy.

 

-----> https://www.rx7club.com/showthread.p...light=flywheel

 

Sounds sketchy. Also a massive waste of money.

Come to think of it, the stock wheel is cast iron. So you'd be welding with very high nickel rod. I really doubt nickel alloy is a suitable friction surface.

Dave