when to replace harmonic balancer?

I'd vote for immediately. Rubber coming out means it's already slipped, and is more than likely off balance. A couple hundred dollars now is cheap insurance, versus a new shortblock IMO.
 
You know what, come to think of it, I get a vibration at high RPM's but a NASTY vibration at high speeds, I mean it rattles so bad it hurts my hand when I have it still on the shift knob. This all started immediatly after installing the new gears so Im figuring driveshaft. But if Im in neutral, say at a stop sign or just in my driveway, and I rev the engine up, as it idles back down..Just as the idle rolls down to exactly 1,000-1,200 RPM, I get a pretty good vibration all throughout the vehicle. It actually shakes my car.
May I possibly be in need of a new HB?


Thanks...
Kris
 
Kris, vibes while stationary are motor related most of the time.
Vibes while rolling can be either (so the usual check is to see if the vibes can be replicated while stationary).

With your stationary vibes, can you replicate the vibes when goosing the throttle from idle up to the vibration spot (1000-1200 RPM)?
There are a lot of engine and engine management dynamics at work when the idle is coming down - if you can make the vibration happen another way, it helps rule out an engine management burp.

Good luck.
 
just got done replacing mine not more than 10 minutes ago... i saw the rubber piece slipping out about a half of an inch so i went and did the deed... :D just a note, make sure you buy one that doesnt need grinding on the water pump... my ford racing balancer which was labeled as a stock replacement needed grinding on the bottom of the water pump. might as well replace the oil seal while you're down there, just remember to put some gasket sealer on the keyway of the crankshaft to prevent oil leaks there, good luck! :cheers:
 
I Broke my harmonic balancer in half last summer. I replaced it with a professional products harmonic balancer, and I have been running a powerdyne supercharger for the last 5 months and I havent had any problems. There are other mods as well