Packard Forum Index » Pre-War (1899-1942)

526 6 cylinder. My engine builder is moments away from completion. He has the damper apart and is wondering about the construction of the damper "gaskets"? in the center. Do these need replaced? Can they be found? (I've had little luck). What would they be made of, or what material should they be replaced with?

Basically I am clueless.

Thanks,

There are a few outfits around that specialize in rebuilding vibrations dampers, have you checked with any of them for advice? It would seem that would be a good place to start.

Another source for info would be those couple of top-shelf restoration shops that specialize in rebuilding engines of that vintage - I've heard of things like having to recast new rubber inner discs and the like, but I have no direct experience or knowledge.

I'm not familiar with the Packard dampener but a lot of them used friction discs. There was a hub and an outer ring that was free to move around. Between the hub and outer ring there was a friction disc or discs. The outer part was free to move but with some resistance. This friction dampened out vibration and prevented the crankshaft from cracking as well as dampening out noise and vibration from the engine.

Newer models from the fifties and later mounted the outer ring on rubber, which absorbed vibrations.

I went through this issue when restoring 2 1929 633's. These vibration dampers use friction discs instead of rubber. Their function is to dampen torsional vibration in the crankshaft.
I could not find anyone with expertise with these style of dampers and considered adapting a later style with rubber but that became too difficult so I restored the old ones as best I could .
Both dampers on the 2 cars I restored had a few broken springs , the metal plates had light rust and the friction linings looked OK after cleaning so I replaced the broken springs with new ones of about the same tension and refitted them after cleaning them
There is no way of knowing how well or otherwise they are working.

If there is no vibration from the engine and the crankshaft doesn't break then it is doing its job. Every piece of metal vibrates at a certain frequency. Hang up a crankshaft, tap with a hammer and it will ring like a bell. If the engine speed coincides with the frequency of the vibration the metal can fatigue and crack after a while. The vibration dampener prevents this from happening.

In your engine this speed will be quite high but within the engine's capability probably around 4000 - 5000 RPM. A speed you won't normally drive at today.