TorqueToYield bolts Mini Cooper

[Dan Raabe]

I torqued my intake cam bolt on my 2007 Mini Cooper S to spec (about 20 Nm plus 180 degrees). I has a problem with the idle and finally took it for another opinion at a local shop. The unloosened the bolt, did some hocus-pocus with the vanos and then torqued up the camshaft with the same bolt telling me they could be torqued to yield twice. I don’t believe you can do that. What is the truth? I am about to replace the bolt with a new one today. It’s the 12th of April. Do I take a chance or go through the brain damage of replacing the bolt? Thanks, Dan Raabe

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[Richard Kirshy]

AFAIK… TTY bolts are a one time use item due to the fact they stretch when the proper torque is applied.
If in your application they are TTY I would check if their claim is true, if not, replace them.

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