Camshaft Bolt Coming Loose After Perrin Pulley Install

[Boxer-Guy]

Originally Posted by WhiteBRZ

You're right, I did mean the crankshaft bolt. I hand threaded the crank bolt in as much as I could until I needed to use my torque wrench. I didn't feel any issues with the bolt while I was tightening it.

You should probably edited the title to crankshaft bolt instead of camshaft bolt because some people might get scared that this kind of thing could happen.

[carbonBLUE]

Originally Posted by WhiteBRZ

I installed the Perrin pulley about one month ago. This afternoon I heard a chirping sound coming from under the hood. When I looked at the pulley the camshaft bolt was slightly wobbly. When I installed the pulley the first time I followed the directions exactly. Today I tightened it again to the recommended lb ft and even a little more this time. Has this happened to anyone else? Anyone have any suggestions in case the camshaft bolt comes loose again?

What you coulf do since youve retightened the bolt, get the car to running temprature, loosen the bolt, drop it in room temperature water,dry, then retighten, this way you can effectively get the bolt tighter a few lbft due to thermal expansion of the threads and the bolt being unexpanded by the heat

[Dimman]

Originally Posted by WhiteBRZ

Is it possible that the crankshaftwas very overtightened and thus stretched out when it was installed at the factory? I only ask because it was definitely torqued to over 150 ft lbs because that is as high as my torque wrench goes up to and it took more torque than that to break it loose when I installed the pulley. Anyone have any thoughts?

Some bolts are designed this way. These are the 'torque to yield' bolts that Calum mentioned.

If that is what the crank bolt is, that means it is a single use/disposable bolt.

I would want 100% confirmation on what this bolt is before doing this mod.

[mike2100]

I checked mine with a torque wrench this morning. After more than 2,000 miles it was still torqued to spec.

[Ranatsu]

When is the last time your torque wrench was calibrated? Maybe you didn't tighten it nearly as tight as you think you did.

[Foobar]

Just checked mine today as well, still locked on tight. I suspect an out of spec bolt, or it wasn't torqued on properly to begin with (not blaming the OP, his torque wrench could've been calibrated incorrectly).

[djdnz]

I would make your way to a Toyota/Subaru dealership (that you don't plan on getting warranty work from :P) and get a new bolt.

In university for mechanical engineering, our mech design prof would always say to use the floating test. If you take a bolt out of something, put it in a bucket of water... if it floats it's good to reuse!

[Foobar]

Originally Posted by djdnz

I would make your way to a Toyota/Subaru dealership (that you don't plan on getting warranty work from :P) and get a new bolt.

In university for mechanical engineering, our mech design prof would always say to use the floating test. If you take a bolt out of something, put it in a bucket of water... if it floats it's good to reuse!

I'd hate to buy new wheel bolts every time I had to take a wheel off!

[Sall]

Originally Posted by WhiteBRZ

I installed the Perrin pulley about one month ago. This afternoon I heard a chirping sound coming from under the hood. When I looked at the pulley the crankshaft bolt was slightly wobbly. When I installed the pulley the first time I followed the directions exactly. Today I tightened it again to the recommended lb ft and even a little more this time. Has this happened to anyone else? Anyone have any suggestions in case the camshaft bolt comes loose again?

damnnnnn,you was lucky my friend.

[JohnATL]

200 miles since I installed mine and it's still torqued to spec. I will be monitoring it.

[3MI Racing]

didn't read the whole thread but just an idea, when was the last time your torque wrench was calibrated?

[wcbjr]

Originally Posted by WhiteBRZ

I only ask because it was definitely torqued to over 150 ft lbs because that is as high as my torque wrench goes up to and it took more torque than that to break it loose when I installed the pulley. Anyone have any thoughts?

A general rule is to not use torque wrenches to remove bolts, only to tighten them. It could damage the wrenches.