Looking at my damper, I see that not only is the rubber pretty dried/cracking, but that the marks appeared to have moved a little bit.

Trying to keep stock look, but don't really want to put just another decades old one on it...

What say CO about a replacement ?

 

You can have your original rebuilt http://www.damperdoctor.com

 

OK...I found damperdoctor, damperdudes, & a couple of others..

Next question..

Is this a 350 balancer ???

I ask because some rebuilder sites & other pics I found show one like this with the little 'half-moon' cutouts at the edge as being a 330 balancer. The 350 ones do not have the extended edge with the cutouts. They're even/smooth from front-to-back.

I pulled this off my car built 04/68. The engine is #'s match, does not appear to ever have been majorly apart, but who knows what happened to it during the 70's.....

 

Thats appears to be a W-31 balancer... nice! Dont loose it.

 

Ha! I wish !
( I do have to admit that years ago when I first saw/heard about the big W-31 balancers, I ran out & checked mine !)

The W-31 bal is much bigger....like space-saver tire bigger...

What say others ??

 

OK....I solved the mystery....

It looks like the 'flanged with little cutouts' or 'stepped' style was used on SBO's up to ~ 1970.

I had seen ones like mine on 330s ala Richard's '66 'vert build...



...and thought all 350s all got the non-flanged ones like this ... (pic from 'f-85')



...but have since found pics like this...
'69 350 w/29K mi...


& a little more digging reveals that 'early' (68-69) 350s got the flanged or stepped damper....

Problem solved, case closed...carry on...

 

I haven't looked at rebuilding a balancer, but here's some info on new units.

Dorman made and oopsies and a large number of them are machined too large on the snout fitting. It should be a press fit, but they just slide on and wobble. Not good.
The dealers sell new ones in the $100 range.(or, at least did in 2000...)
The generic replacement that's about $100 at the big online parts sources (Powerforce is the manufacturer, can also be sold under other names) sometimes has the pulley mounting boss incorrectly machined. Mine is fine, however.

There is a chance that going non-stock throws off the engine balance.

 

I've seen three different balancers on 1968-72 350 engines and haven't figured out why. They all have the same crank and flexplate or flywheel if manual transmission. I vote for having yours rebuilt at one of the vendors you mentioned. You could also watch ebay as damperdoctor lists rebuilt units now and then. You might get one off ebay for less than the standard rebuild price. John

 

I've seen info about this. I'm trying to avoid aftermarket parts wherever possible for just this reason. Seems like its a real crapshoot whether an A/M part will fit/work or not. I'd rather rebuild and/or use an old OEM part than gamble on A/M & endure hours of frustration trying make it work.

Yes. I've now seen 3 different types as well. The stepped/cutout one like mine and two sizes of non-stepped ones. (# 4 would be the holy grail W-31 monster).

I'll keep an eye on eBay, but definitiely plan of having mine rebuilt because as I cleaned it, little bits of the rubber came out/off.

My machinist called yesterday AM and said he needed mine (along w/flywheel & pres. plate) as he had my crank ready to balance. I didn't have time to get mine rebuilt without keeping him waiting. I took my crusty one over. He said it would work fine for balancing and that he would check the balance of the damper first and note it. After the motor was done I could get it rebuilt. He would check the damper post rebuild and if needed, tune it so it matched the pre-rebuild spec thus keeping everything in balance. He also mentioned that, in a pinch, he can get by with just the core part with the counter weight since the ring is usually pretty neutral.

Thanks for all of the input !..... Eventually I'll post a pic of it when its rebuilt.