Just removed my exhaust manifold from my '63 225 I'm rebuilding. It was difficult to remove, due to some rusty manifold-to-tailpipe flange bolts. But finally got them off today.
The manifold is the earlier style with the semi-closed choke pocket. I cannot tell if it's original to the car, but see the numbers on it, maybe some of you can identify and let me know. I do notice the CDPD on it: perhaps this is original equipment? I remember reading somewhere here that manifold engineering and manufacturing progressively added 'ribs' to the manifolds to prevent cracking, but I don't remember what was specific for 1963.
The manifold has no visible cracks, and worked fine before I removed it. The heat riser flap is frozen and the counterweight had been held in place for years and years with a jury-rigged wire; I assume in the open position (though it doesn't look 'opened' to me). Aside from the frozen riser, the only other issue to deal with is one of the long intake manifold screws broke off when I was trying to remove it. You can see the broken screw where the manifold V's together.
Is the manifold worth the trouble to take it to a machinist and have them machine out the broken screw? I haven't seen reproduced manifolds that have the earlier-style semi-closed choke pocket. How necessary is this for proper choke functioning? AND, if I manage to solvent-up the heat riser flap and get it moving correctly, the thermostatic heat spring seems loose: is this something to replace?
Let me know your thoughts guys, thanks.
