Cam Bolts Broken After Replacement

[jet_dogg]

Well, an M6 takes 12NM which is 9 ft lb, you gave them more than 30% so not ideal. I believe these are 8.8 class, if they are higher grade then you were fine, but I am almost sure the OE bolts are 8.8 class

for sure some one will correct me if I am wrong

I was going to post this.

The smaller the bolts the more critical slight torque variances become.

[Sid_E46]

For the OE bolts, yes. Especially since they're already kinda lubricated with oil +/- loctite when you're installing them.

Technically the OE bolts are upto the task if an appropriate thread locker is used. But it's very easy to overtighten. Stronger bolts gives you more wiggle room in that regard.

This is making me paranoid to check my own car now.

This wasn't as much of an issue in the 01-04 cars though correct?

[terra]

I believe I may have done 12 ftlbs but would that be enough to cause damage.

For the OE bolts, yes. Especially since they're already kinda lubricated with oil +/- loctite when you're installing them.

Technically the OE bolts are upto the task if an appropriate thread locker is used. But it's very easy to overtighten. Stronger bolts gives you more wiggle room in that regard.

[Sid_E46]

Well, an M6 takes 12NM which is 9 ft lb, you gave them more than 30% so not ideal. I believe these are 8.8 class, if they are higher grade then you were fine, but I am almost sure the OE bolts are 8.8 class

for sure some one will correct me if I am wrong

Yep, oe is 8.8 grade.

[maupineda]

I believe I may have done 12 ftlbs but would that be enough to cause damage.

Well, an M6 takes 12NM which is 9 ft lb, you gave them more than 30% so not ideal. I believe these are 8.8 class, if they are higher grade then you were fine, but I am almost sure the OE bolts are 8.8 class

for sure some one will correct me if I am wrong

[Sid_E46]

9 ft-lbs. clean the oil off the threaded holes and the surface at the end of the cams where the sleeves mate on. Metal to metal and no oil here.

I believe I may have done 12 ftlbs but would that be enough to cause damage.

[sapote]

We are going to use the lang racing bolts and 243 loctite this time. Is 9 ftlbs the recommended torque?

9 ft-lbs. clean the oil off the threaded holes and the surface at the end of the cams where the sleeves mate on. Metal to metal and no oil here.

[Sid_E46]

We are going to use the lang racing bolts and 243 loctite this time. Is 9 ftlbs the recommended torque?

[maupineda]

I think the issue is you did not use the right locker and again, should be as clean of oil as possible.

[Slideways]

It is stated on the 243 -

[Sid_E46]

Loctite 243 is oil tolerant; the standard blue loctite 242 and red are not.

We used the red gel loctite, that isn't oil resistant?

[Slideways]

Oh ok, I'm not quite sure. The car is getting new cams so let's hope it doesn't happen again. We will probably use a decent bit more red loctite this time.

What torque is recommended for these bolts? And does going over that number a little pose a risk?

Loctite 243 is oil tolerant; the standard blue loctite 242 and red are not.

[Sid_E46]

Not as a tool, but the hammering effect when there was plays between the sleeve and the loose bolts.

Oh ok, I'm not quite sure. The car is getting new cams so let's hope it doesn't happen again. We will probably use a decent bit more red loctite this time.

What torque is recommended for these bolts? And does going over that number a little pose a risk?

[sapote]

We did not use a hammer to remove the previously snapped bolts, just used a pick and spun them out. We wouldn't have even caught this if we weren't swapping out his cams.

Not as a tool, but the hammering effect when there was plays between the sleeve and the loose bolts.

[Sid_E46]

I'm interested of seeing the cam sleeve 6 holes, and how bad they had been distorted after hammering on the bolts to cut a notch.

We did not use a hammer to remove the previously snapped bolts, just used a pick and spun them out. We wouldn't have even caught this if we weren't swapping out his cams.