Need help asap: B4 crank sprocket issue!

Abacus, if the car suffers (knocks on wood) a failure in the future on the crank sprocket, please update the thread.

I replaced my crank pulley at the time of my timing belt change 50k ago, and it's coming around again. At the time, I replaced the crank seal, pulley and bolt. I got lucky with mine - there was no wear on the crank snout or the timing belt pulley. I plan on taking mine off again and replacing the bolt again when I re-do the belt in the spring.

I do recall mine having no perceptable rotational motion relative to the crank snout before I torqued it down. I would be hopeful but concerned to have only the crank bolt as the thing resisting torsional forces applied by the tension in the cam belt as well as the accessory belt system.

If this were my car, I would invest in a clutched alternator pulley to reduce the forces applied to the crank pulley by the rotational mass of the alternator.

Windex said:

If this were my car, I would invest in a clutched alternator pulley to reduce the forces applied to the crank pulley by the rotational mass of the alternator.

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I COMPLETELY forgot to mention this!

I installed a Gates 37010P clutch pulley, when I replaced the timing belt 10k miles ago. This pulley can be had for a VERY reasonable price from Amazon.

That alone really seems to reduce the oscillation in the serpentine tensioner. Which, I think, translates to reduced oscillation in the timing belt, reducing wear and forces negatively impacting the crank snout/timing pulley failures.

Tony

I will update the thread if there is a future problem with the sprocket, or if we have to remove it again for seal replacement.

I'll mention the pulley to revkev and leave it up to him. I bought one of them off Amazon but have not installed it yet on mine (and I'm running the original crank sprocket), but I will. The Mrs' B4 has a cold start chirp, so I'll probably toss one on hers and upgrade the harmonic balancer as well.

Thanks for the link on the sprocket tool, I wish I could see one in real life to see how well it's made.

Have you seen metalnerd's crank-yank tool? A little spendy, and the fact that you can rotate the head, makes it a little easier to use.

Tony

Abacus said:

Thanks for the link on the sprocket tool, I wish I could see one in real life to see how well it's made.

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I've got one and its one beefy tool. Weighs a ton. Nicely made. Not as versatile as Metalnerd's adjustable version, but it works great and, of course, 1/2 the price.

Thought I'd update: Revkev's car is running fine and he is consistently getting over 50 mpg, which he has never breached before. The car is still running flawlessly.