What causes the spring on Clutch disc to crack ?

[Mr Nice]

Just wondering what would cause 1 of the 4 springs on the clutch disk to crack ?

The car is a 2000 Honda Accord (80% highway miles) that is adult driven and not abused with 120K miles.

 

[Chris142]

every time you press on the clutch those springs get compressed then they expand. eventully they fail from just normal wear

 

[Kiwi_ME]

Probably a minor manufacturing defect like an imperfection on the surface of the wire. These are compressed every time the torque through the clutch varies and would be designed for a nearly infinite life.

 

[yonyon]

Mostly it's just a matter of having a spring that was born to die young. That said, make sure you aren't running with a misfire (you couldn't fail to notice this) or a broken engine/trans mount. A chattering clutch could also be bad for those springs but presumably if you had that issue it would have been fixed when you replaced the clutch.

 

[mechtech2]

Just another way for a clutch to break.

 

[Tegger]

Originally Posted By: LT4 Vette
Just wondering what would cause 1 of the 4 springs on the clutch disk to crack ?

A defective spring. Was this an OE clutch?

It is possible that the break was due to poor clutch technique, but that situation would be made abundantly obvious by looking at the retaining lips on the flywheel side: If they have very deep grooves in them, then somebody's not too good with a manual transmission.

 

[Mr Nice]

It was the original clutch, pressure plate and T.O. bearing.

Maybe it had a bum spring ?

 

[Tegger]

Originally Posted By: LT4 Vette
Maybe it had a bum spring ?

What do the spring retaining lips look like on the disc? Worn to the point where some of the lips is non-existent?

 

[Cujet]

I'm 100% sure the clutch spring has nowhere near the number of actuations a valve spring has. Yet, we don't see valve spring failures often.

My guess: Made in China, from recycled steel, which includes melted Ford Crown Vic's and Chevy Caprice's and a few old battleships.

On a more serious note, recycled steel is used for such things now and it's utterly impossible to control the quality.

 

[Tegger]

Originally Posted By: Cujet
I'm 100% sure the clutch spring has nowhere near the number of actuations a valve spring has. Yet, we don't see valve spring failures often.

Valve springs are not subject to their coils being slammed together at regular intervals. Clutch springs are. That's the difference.

As I've said twice already, the telltale would be the appearance of the retaining lips on the friction disc's center carrier.

As for recycled steel, that has been used for many, many decades; it's old technology, and difficult to mess up, even for Red Chinese working under automaker specs. Anyway, ALL iron must be converted to a non-oxidized state, whether it's fresh from the mine or reclaimed from prior use. And flaws in steel can come in the form of streaks and slag inclusions, not necessarily corrosion; inspection of the fractured surfaces can reveal those.