flywheel bolts broken

[QuebecmkIII]

ok, I explain my story, after some donuts with the Supra, I was unable to shift any gears when the car is running, just when is close. And a grisha sound was audible when I press the clutch...
So I uninstall the R154 and at my surprise,(I anticipated a broken clutch) but 2 flywheel bolt have been broken. I found the head of 1 bolt during the uninstallation. So I supose that it was that motherfucker head bolt who block the clutch to touch the flywheel and it's why the gear won't engage.

My 2 question are
-What can cause that, I don't want that problem again
-I know nothing with the clutch but I want to know if the clutch and the pressure plate are in good condition?(It's an Aisin)
And my future goal was maybe 350-380 whp, there will resist?
For sure I will command ARP bault for the flywheel!
thank

 

[QuebecmkIII]

Nobody can help me?

 

[adampecush]

My 2 question are
-What can cause that, I don't want that problem again
-I know nothing with the clutch but I want to know if the clutch and the pressure plate are in good condition?(It's an Aisin)
And my future goal was maybe 350-380 whp, there will resist?
For sure I will command ARP bault for the flywheel!
thank

1. Insufficient or excessive preload (torque) on the bolt can lead to it breaking. When re-installing, follow the TSRM specifications for tightening (torque value, oiling of the bolts, tightening sequence) EDIT - low grade bolts can cause this too (no photobucket access here at work)

2. Inspect the clutch components as per the tsrm (http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=CL&P=12).
Chances are the power range you are after will be a bit too much for the clutch on hard launches (I was at around the same power level and a hard 1st gear launch would cause the clutch to slip)

 

[CyFi6]

Wow, it looks like someone went to the hardware store and picked up some screws that threaded into the holes in the crank... Definitely invest in some REAL flywheel screws from Toyota

 

[berniek]

Do you have the stock front crankshaft damper or do you have an underdrive pulley? You need the damper to eliminate torsional harmonic vibration in the crankshaft. Flywheel bolts can break due to torsional vibration.

BernieK

ok, I explain my story, after some donuts with the Supra, I was unable to shift any gears when the car is running, just when is close. And a grisha sound was audible when I press the clutch...
So I uninstall the R154 and at my surprise,(I anticipated a broken clutch) but 2 flywheel bolt have been broken. I found the head of 1 bolt during the uninstallation. So I supose that it was that motherfucker head bolt who block the clutch to touch the flywheel and it's why the gear won't engage.

My 2 question are
-What can cause that, I don't want that problem again
-I know nothing with the clutch but I want to know if the clutch and the pressure plate are in good condition?(It's an Aisin)
And my future goal was maybe 350-380 whp, there will resist?
For sure I will command ARP bault for the flywheel!
thank

 

[QuebecmkIII]

Do you have the stock front crankshaft damper or do you have an underdrive pulley? You need the damper to eliminate torsional harmonic vibration in the crankshaft. Flywheel bolts can break due to torsional vibration.

BernieK

I don't think I have the original crankshaft pulley, it seem to be in aluminium but I don't see the brand.
That might be a good reason...
thank

 

[hvyman]

i would re-surface the fly wheel, replace the clutch disc(looks chewed up), check to see if you can resurface the pressure plate, and get some arp fly wheel bolts.

 

[GrimJack]

Those bolts are definitely not stock. I suspect they just weren't strong enough.

At the very least, get new bolts from Toyota. Better yet, get new ones from ARP.

 

[QuebecmkIII]

Thank you guys!:drink1:

I will command ARP bolts and resurface the flywheel and buy new clutch kit just to be on the safe side.
Probably a feramic clutch 6 pucks would be the best for me and I hoped to have any problems...

 

[sylquebec]

Question he forget to ask : Does the flywheel bolt are thread in the flywheel itself or only in the crank? Because it will be hard to remove the broken one if they are thread in the flyweel...

 

[IJ.]

Replace the front pulley with a damper as it's not doing your crank any favours.
(nice call Bernie)

 

[QuebecmkIII]

Question he forget to ask : Does the flywheel bolt are thread in the flywheel itself or only in the crank? Because it will be hard to remove the broken one if they are thread in the flyweel...

The bolt are not screwed in the flywheel..

 

[gaboonviper85]

hey frenchy...get a stock or ati crank pulley on your car asap...if you don't you'll be back here very soon asking how to rebuild a motor fucked by rod knock!!!

Arp flywheel bolts are a good investment but make sure to read the arp instructions!!!

 

[supraduper]

yes, the bolts are obviously not stock.... but isnt anyone going to mention how nashy overheated that flywheel and pressure plate is..... ive never seen the ammount of blueing of the pressure plate, that is evident on his...


all that heat with subpar bolts....

 

[adampecush]

are you talking about the blueing on the pressure plate springs? Because that is from the heat treatment of the springs, not the use of the pressure plate. The pressure plate and flywheel friction surfaces don't look all that bad.

 

[ForcedTorque]

Please take all hardware store parts off of the car before you ever try to get to 380HP or more. Maybe you should post some motor pics for a little more advise.

Driftmotion sells ARP Flywheel bolts for $25 dollars (USD)

Don't waste any time on the damper, even if you have to source a Good used one. You don't want it to have ANY pieces broken off. Torque specs for the bolt holding it on is 195 Ft-Lb.

 

[gofastgeorge]

Dang, where did you come up with those cheesy plated bolts?

Get the APR bolts.

And I would toss that flywheel in the scrap pile.
Notice all the heat cracks in the surface ?
I had one like that once, and the cracks went so deep, that even after it was re-finished, they were still visable.
A flywheel like that can explode (and take your feet off in the process).
I have seen it happen.

 

[tbcmorris]

Those bolts are definitely not stock. I suspect they just weren't strong enough.

At the very least, get new bolts from Toyota. Better yet, get new ones from ARP.

make sure you check the threads and follow tourge specs and use some lock tight

this is what happens if all those bolts break: :3d_frown:

 

[gaboonviper85]

Skillz^^^

 

[tbcmorris]

I tend to drive hard