I've read enough about the problems with the harmonic balancer and crank pulley bolt to be completely paranoid -- I finally got my 3.0 liter back together after a blown head gasket (actually, the gasket wasn't compromised, but the cylinder head had actually lifted up/warped in an area -- thanks to a rebuild that had some head bolts over the 72lb torque and some only hand/socket tight!)

Anyway, I have her back together and running -- but my final task of setting the timing revealed a pulley mark that seemed to fluctuate between 5 and 6 degrees BTDC... there wasn't even a "gap" between the marks, but it definitely wasn't rock steady. Is this definitely a sign of separation of the two parts of the balancer, or could incorrectly tightened belts, pulley flaws, etc. be causing this minor variance? I've read wandering means the pulley is about gone, but didn't know if there was a limit -- and it had been so long since I even checked the timing I don't remember what it was doing then.

If bad, should I even be driving the truck before fixing, or since I didn't see any visual damage at the time of reinstall, I probably have a few more miles of life in it?

Lastly, I used a new crank bolt during reinstall -- if I replace the balancer, do I need to replace the bolt yet again? As in, is it trash once torqued and released... or is it a time/mileage thing... meaning mine is still brand new?

I'm thinking all will be replaced if that's what it takes to be sure... just didn't know if I'm risking some major damage just by driving out to the dealer to get the replacement part.

As always -- I appreciate the opinions,
Bryan

Cylinder head bolt torque specs were revised to 80 lb-ft cold or hot in a TSB for the 3.0L engines. If you followed the old spec of 72 lb-ft, you are inviting another issue like you just experienced. If you didn't use the 80 lb-ft spec, I'd advise you to go back and re-torque the heads to 80 lb-ft.

As for the damper, the fluctuation could be wear in the distributor, but I wouldn't worry about 1 degree. Rev it to 2000 rpm, hold the throttle steady and see if the timing mark when advanced stays "relatively" steady at a constant rpm. It won't be exactly stable at best - it just shouldn't be moving around by more than about 1 degree at idle and 2-3 degrees above idle, and even those aren't exact numbers. Timing is affected by a number of inputs to the ECU and any slight change in air/fuel/spark will show up on the timing light. If it gets too bad, you should go through the vacuum lines and all components you can test before you condemn the pulley.

If you replace the balancer, it's not necessary to replace the bolt again as long as you have the new style. BTW, there was a torque change on that contained in the bolt TSB - hope you have it tight enough. The new torque spec for the bolt is 134 lb-ft (+/- 3 lb-ft).

Frank

Frank,

thanks so much for the opinion on the pulley -- and I'll definitely re-torque that to 135. I did do the heads to 72 ft lbs. I hope this is something I can put 500 or 1000 miles on before re-torqueing... Doing the job the first time was tough enough, I need a bit of a rest!

Again, much thanks,
Bryan