Does the keyway slot have any correlation to the actual engine timing?  I would believe that mass production of these crankshafts were done in such a way that they would be compatible to the damper pulley assembly, pretty much as a matched set.  If not and they were manufactured helter skelter where ever the milling machine decided to cut the slot then you would have a hard time installing a pulley and finding TDC.  Reason I ask is I was told when rebuilding the harmonic balancer, the balance ring is vulcanized into the correct position in the pulley assembly.  BUT my balance ring has no marks on it, the small "V" is only on the edge of the first pulley. I believe in correct factory timing settings to make it run decent.

 

If you want to verify TDC use a Piston Stop and temporary Pointer. Mr Gasket makes a Timing Tape for Small Block Ford which would be very close to Accurate on a Y Block which has a slight difference in Diameter once U verify where TDC is..

  

I put the timing tape on my Y (312) (probably a Mr. Gasket) and it has lasted for over 10 years.


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

55charliebird.  The 'Bird crankshaft vibration damper assembly is a different animal from the y-block passenger car and truck units. 

The donut weight on the 'Bird damper was originally secured in place by a vulcanized rubber material.  The donut weight on the 'Bird damper has no timing marks on it associated with its position on the steel damper assembly.  The timing mark on the edge of the inner pulley of the 'Bird damper is located related to the woodruff keyway going through the crankshaft mounting surface of the 'Bird damper.  On the 'Bird damper, the timing mark on the inner pulley cannot move out of orientation with the damper's crankshaft woodruff keyway opening

After the donut ring on the 'Bird crankshaft damper is re-vulcanized to the steel damper assembly by the re-builder, the damper assembly should be dynamically balanced as the donut is likely not located in the same place as it was when originally manufactured.  IF this re-balancing of the 'Bird damper assembly was not done by the company that remounted and vulcanized the donut in its correct location, it should be done by the engine re-builder.

Note that the damper re-builder in Oregon gives a lifetime warranty on their work and that Damper Doctor offers a three year warranty as I recall.

Hope this helps.  


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York

The keyway on all y-block cranks is in the same position.  Exactly how they referenced that during machining, I don't know.  There are tolerances in manufacturing so there will be slight variation from one crank to another.



Lawrenceville, GA

Here’s the link to the thread that Dennis K posted awhile back giving the actual allowed factory variance in the machining of the keyway slots.  If taking stack ups into consideration where you’re dealing with key slots in both the damper and the crankshaft, then simply double the allowed variance.  Even doubled, the variance is still ‘tight’.
http://forums.y-blocksforever.com/FindPost9095.aspx

Lorena, Texas (South of Waco)

On those Thunderbird dampers, they were all originally marked with a 0 for TDC and marks at 2° intervals up to 10°. Those marks do get hard to see with paint and/or erosion of the surface over time.  Here are pics of two T-Bird dampers sitting in the shop and one of them has visible marks while the other had just enough rust to have made the factory markings almost disappear.  If not knowing where to look on the rusty damper, the existing marks could be easily overlooked.  Where the markings are illegible, the damper will have to be remarked accordingly before permanently reinstalling it on the engine.
 

 

Lorena, Texas (South of Waco)