I finally mated the head to the block and did a final head bolt install. OEM gasket, OEM BMW bolt kit, 22ft.lbs; 90' and 90', correct sequence etc. Used ARP bolt lube on bolts, block holes were clean.
3 bolts (#2, #12 and #13) gave me a weird feel at the end of the second 90'. It felt like the tension got released at the last 20-30' of the turn. Almost felt like I broke a bolt.
I set my torque wrench to 60ft.lbs and all other bolts were holding that torque fine except the above 3, they started to spin a little under 60ft.lbs. I wasn't happy and panicked a little...... decided to back #2 out and see if it was broken.
It was not. I put that bolt back in and decided to crank it to 60 ftlbs and then to 70ft.lbs as all other bolts (except 2, 12 and 13) were holding 70ft.lbs just fine. All 3 bolts took 70ft.lbs just fine.
My question: I know reused bolt #2 is compromised as it's TTY. Did I screwed up with torquing them down instead leaving them alone? Should I bite the bullet and start from scratch (new gasket and bolts)? Again, 60 and 70 ft.lbs did not move 11 bolts that felt fine during the install, only the weird 3 were able to move under 60ft.lbs. The above mentioned #2 bolt that I backed out, stopped about 120' degrees past were it initially stopped with 22ft,90-90. #12 and #13 that I did not back out, stopped about 50' degrees past were they initially stopped with 22, 90-90.
3 bolts (#2, #12 and #13) gave me a weird feel at the end of the second 90'. It felt like the tension got released at the last 20-30' of the turn. Almost felt like I broke a bolt.
I set my torque wrench to 60ft.lbs and all other bolts were holding that torque fine except the above 3, they started to spin a little under 60ft.lbs. I wasn't happy and panicked a little...... decided to back #2 out and see if it was broken.
It was not. I put that bolt back in and decided to crank it to 60 ftlbs and then to 70ft.lbs as all other bolts (except 2, 12 and 13) were holding 70ft.lbs just fine. All 3 bolts took 70ft.lbs just fine.
My question: I know reused bolt #2 is compromised as it's TTY. Did I screwed up with torquing them down instead leaving them alone? Should I bite the bullet and start from scratch (new gasket and bolts)? Again, 60 and 70 ft.lbs did not move 11 bolts that felt fine during the install, only the weird 3 were able to move under 60ft.lbs. The above mentioned #2 bolt that I backed out, stopped about 120' degrees past were it initially stopped with 22ft,90-90. #12 and #13 that I did not back out, stopped about 50' degrees past were they initially stopped with 22, 90-90.
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