Vacuum Advance Mechanism on my Distributor

[NorthWestcuda]

I don't think my vacuum advance mechanism on my distributor is working and need some verification from you pros.  I tested the vacuum advance mechanism with one of those hand vacuum pumps.  Basically all I did was take the rotor cap off the distributor and see if I could get the vacuum mechanism to move (advance) while using the hand vacuum pump. It didn't move at all.  Doesn't that mean that my vacuum advance mechanism on the distributor needs replaced???  If so, does anyone now where to look on the distributor to get a distributor part number? 

[Moparal]

does sound like a blown diaphram, but see if the arm is hooked on the plate and that the plate is not jammed or stuck. Then, the parts house goes by auto or standard trans, year model, engine size. things like that

[NorthWestcuda]

Thanks I'll check that.  The problem is that this is a 440 engine sitting in a 73 cuda.  And I can't find any engine numbers at the bottom of the engine to figure out what year the engine is.  NAPA just said to find a part # on the distributor.

[Moparal]

Tell them 70 points distributor for a cuda 440, and the advance has no electric wires on it. Even a 69 advance will work from a road runner. Mine is off a 68 imperial with a 440

[Aussie Challenger]

  Check to see if the hand held vac holds vacuum, if it does then the disphram is OK and there must be a linkage problem or the base plate is locked or welded. I spot welded base plates on some hi performance vehicles to give the plate more stability and to make sure that nobody reconnected the vac advance giving it tooooo much advance.   

[Chryco Psycho]

the advance plate could be welded or stuck , will the plate move ?

[sleepychallenger]

if you find somewhere that has the vacuum advance, let me know. i couldnt find one except on ebay. everyone says that they are discontinued

[NorthWestcuda]

The plate will move and is not welded.  I also noticed that the "magnetic pickup signal wheel" (don't know the exact name of this thing) which sits at the top of the distributor shaft has some nicks or pieces gone.  Does this indicate anything?  I thought it would indicate a loss shaft but the shaft has no wiggle at all.  Should I replace this?   The picture is not the best but notice the right hand side "break".

[NorthWestcuda]

I think I'm going to try and buy a new distributor instead of paying $50-$60 just to buy two\three replacement pieces.

[Chryco Psycho]

the reluctor can hit the pick up coil & break , the reluctor is universal & can be used  from  a small block dist