Cam pulley wear/Cam bolt re-usable?

[dislexicmofo]

Two camshaft sprocket related questions. First, Is the bolt re-usable? I dont see another in my timing belt kit.

Second, I see some wear on the inside of the sprocket, since I am still diagnosing the belt failure I thought I would ask about it. It doesn't look like anything that would even throw off balancing but I like to play it safe, flood the forum with questions, and over analyze things

 

[jasonTDI]

It's fine.

33ft lbs is the specs but others set to 40 ish.

Make sure you are using lock tools.

 

[Ski in NC]

Taper joint might have slipped when valves hit during belt failure. Clean up taper inside pulley and make sure it is a good fit on the cam nose. No burrs, raised metal, no rocking when fitted, etc. And yes, that 33ftlb seems way low in my mind.

 

[tditom]

bolt is meant to be re-used

 

[AndyBees]

I'd say it is a good possibility that the incident was the other way around. The Cam Sprocket slipped in the Morse Taper, thus allowing Valves to Kiss Pistons and break the TB. But, based on the view in the photos, there doesn't appear to be enough "scuffing" to indicate more than two or three degrees rotation.......the scuffing could be from the last TB job as it was being installed.

If you had TB failure, regardless of what caused it, there is a very little doubt that one or more Exhaust valves did hit piston(s).

Yes, as suggested, the spec is 33 ft lbs, but low 40s is best and works! Also, as stated by others, the bolt is re-usable!

 

[dislexicmofo]

Thanks for the help! While were all here, I'm having trouble figuring out one thing here, when I set the cam timing, should the sprocket be on and torqued? Keep in mind I dont have a belt on yet.

 

[tditom]

You don't set the cam timing. You lock it at #1 Top Dead Center. When the flywheel (crank) is at its TDC mark and the IP is pinned at its reference point you slip the cam sprocket onto the tapered stub. follow the directions.

 

[Mavrick]

Your pulley looks good and you can reuse the bolt. Blue lock-tite wont hurt.

 

[Powder Hound]

Don't put locktite on the taper. Just make sure the inside of the pulley and the taper on the end of the cam are both very clean and dry. When it is done properly and torqued down, they mate together such that the next time the cam sprocket is removed, a puller is required and there will be an audible snap when the pulley is pulled free (loosened) of the cam.

If you want to use some blue, do it on the bolt threads that hold the cam. But whether you use locktite or not, make sure the bolt threads are clean and dry and use a good torque wrench to insure it is tightened correctly.