Willing to part with the Cast Iron Ring Adapter??
PLEASEE!! I bought my first Caddy 6months ago and just found this crack yesterday.
I honestly don’t know what to do to fix it besides replace it. I hope nothing else is broken. Not sure if the bell housing being a lil bent will affect the rear main.
Josh, From the many 1964 parts and driver cars I have seen, this is a more typical stress crack. If the adaptor ring to engine, and transmission to adaptor ring bolts are all torqued appropriately, AND there are no other issues that seem related to this, I would probably leave as it until you pull the engine out again. With that said, these ARE HARD TO FIND! And, if Alexander will sell his, you might want to jump on his offer. I know I have at least a 1/2 dozen contacts looking for these on my Wait List, and they are getting harder to find uncracked as the years go by. I remember, probably around 2005 I had about 6 on hand now as mentioned I am minus 6 in terms of customer needs.
Back to your crack, the adaptor ring is serving it's purpose to "adapt" the "Buick Borrowed" transmission to the back of the engine, and server as a spacer so just the sight of this stress crack doesn't cause me that much concern, but if there were other issues, especially vibration and noise, etc, I would look to find the cause. As Russ, mentioned, you should have a starter bracket that braces the starter to the RH side of the engine block. If it is mentioned, the torque of the starter can crack the ring but often in different location than yours. Here is a picture of that starter bracket:
For the adaptor ring removal, you could either pull the engine with adaptor ring attached and then remove adaptor ring from back of engine, or drop the transmission and remove ring off back of engine still sitting in place. If you need to also address a leaking front transmission seal, dropping the transmission might make more sense as you could still get to the rear engine seal but the oil pan has to come out which requires loosening a few items from below as described in the 14 steps on page 9-23 section 19.a in your shop manual. Just to NOTE: If you do not have a shop manual that is a must for removing engine, transmission or any work on your car. Removing engine or transmission is a more involved process, but nothing anyone with basic mechanic skills couldn't tackle, especially stepping through the Shop Manual.
Interesting. I was just doing some research on the difference between a flexplate vs a flywheel. Could this be a reason why every once in a while if I come to hard stop my tranny will jump into neutral? Ill run it through the gears and it will fall back into gear.
In addition to the adaptor ring replacement, is there a way to protect that area, like a Skid plate? I feel that Im just going to scrap it up eventually.