Broken Pressure Plate Bolt Risky or Not....Opinions Please.

[jspaeth]

This weekend, my buddies and I installed a new flywheel (ACT Prolite) and clutch (ACT 6 Puck Sprung) onto my SR (already had ACT Heavy Duty PP).


The PP bolts are 12mm.....the ACT instructions said to torque bolts of that size to 50 ft-lbs, but the FSM directions said 25-33 ft lbs.


After getting them all tightened down with a ratchet (in order of course), we started using the torque wrench, set at 45 ft-lbs.

Basically, we tightened a few down to 40 or so with no problems......however, one of the middle bolts (there are 9 bolts clustered in groups of 3) snapped off....we just left it and figured it would be ok....but needless to say, we torqued the rest down a little more gently to about 30-35.


My question is.......Given that there are 9 bolts, and the torque spec is ONLY ~30 ft-lbs, should it be safe with just the 8 bolts holding it in there?

I've already driven the car for ~200 miles and done some hard pulls (no hard clutch let outs though) and there has been no problems.

My rationale for it being okay (in my head) is that the torque specs are so low (25-30 ft-lbs) that they must not be carrying that massive of a load.

Plus, the one that broke is in the middle of a group of 3, with the outer two hopefully providing the most support anyway.


Of course, the next time I do a clutch, I am going to buy APR PP bolts and drill out the old one.....


I hope I don't break anything :-/

[murda-c]

The fact that you're missing a bolt means it's torqued down unevenly, which means it's warping slightly and out of balance, which means the other bolts are more likely to work their way out. It could end in catastrophic failure.

I'd just get that bolt out now and replace them all.

[clark]

do it right the first time. get the arp pressure plate bolts and never worry about it again. i too broke them and replaced with not arp, but high grade black oxide coated bolts.

[jspaeth]

:-/

This sucks....the car feels good and all, but I am kind of worried too....

Doing the clutch was NOT fun, and I don't want to do it all over again.

But I am a stickler for doing things right......I just figured they weren't carrying much load anyway (25 ft-lbs is not much) so 1/9 wouldn't be enough to kill it....

I guess I will think about when I can fix it....I really should have just been patient and drilled it out then and there and bought a new bolt, but my buddies (with more experience) said it should be fine and kind of just were hurrying me along.....

I am returning my Craftsman torque wrench to get the one with the digital readout.

[g-via]

if you were a real stickler for doing things right, you would have corrected your mistake when the transmission was out.

PP bolts snap really fucking easily though, I realize this.

[roboticnissan]

eh i broke one but i really needed my car running for work so ive been driving on it for a few months. no problems so far but i have a stock ka24de

[Not You]

Fuck those digitals get a Beam TQ wrench. Those PP bolts are important, fix it, you dont want to be "that guy"

[jspaeth]

Okay....just talked to ACT tech support, and after explaining what happened and going through some reasoning, I was told that I shouldn't really worry about it.

....obviously they can't GUARANTEE anything in writing, but he said given the low torque specs on those bolts, it really shouldn't be a major deal.....


Next time I do a clutch, I will certainly fix it though.