I would think a bad balancer would be more of a vibration than a rumble, however if it is bad the timing marks may be off and the timing may be advanced. I'm not really sure. Most of my engine work has included a new balancer.
Sounds like good advice to me---a new balancer it is. Vibration is probably a better desciption for what is going on there any way. I will consider it an investment and carry it over when we rebuild and can afford a better head and intake for it. Thanks again. ~Panama Macs~
O'reilly's doesn't have and can not get a harmonic balancer for the 250 six cylinder. Any ideas? ~Panama Macs~
might try this guy http://www.damperdudes.net//index.php?cPath=25&osCsid=693cde6ab7d20f455ebc2a2470c96050 . I don't know anything about them, but I got it off of "Classic Inlines" forum.