I don't if I should've continued the old post, but.............
I had to replace the harmonic balancer on the weekend on the Bonny. All the classic symptoms. Lloud clattering sound coming from underneath the */C - it is easy to think that it is the */C itself. It only happened at idle - goes away under load. Small debris of rubber pieces under the car.
I took off the two belts. All other pulley moved without any noise or play, so I figured it was the HB that was gone. Ordered an aftermarket one for $178 (the Delco one was going for $400).
I took some pics along the way that may be of help. The job is pretty straightforward, but I think two things are a must: an impact gun and the HB puller. Took me 4 trips to the parts store to get the job done.
You need a 15/16" socket to the center bolt off. I had a use an impact wrench (you don't need to hold the flywheel if you use the impact gun). The flywheel cover is near the oil pan (you need to take this off also when you remove the oil pan).
The center bolt:
Old HB with the pulller installed (I used three 1/4" bolts 3" in length):
Old HB: yep, it was the problem. The rubber was basically split from the metal:
When installing the new HB, you have to hold the flywheel. I just used a small pry bar.
One issue that I ran into was that I could not tighten the center bolt after installling the new HB to 110 ft lbs with hand - it was way too hard. So we tightened by hand as much as possible, then used an impact gun some more. We were afraid to tighten it too much in fear of breaking the bolt.
The car is running fine now, but I am still concerned that we didn't torque perfectly. Any thoughts?