To-30 manifold update

Well it's been months ago that I ordered a new manifold for the cracked one on the 1951 TO-30. It is new to me, was my Grandfathers and has
been in the family over 50 years that I can verify. I also ordered all new intake hoses, radiator hoses and thermostat, along with other parts.
Tonight I got around to starting to fix it. I started to remove the hood as I also have a broken radiator bracket that needs soldered. The first bolt
came right out. The second one just spun and spun. I see now the square nut has a sheet metal holder for the nut not to turn. The first side
was rotted away and I put a wrench on it. Guess I gotta cut the sheet metal away on the second side to get a wrench on that one.
I removed the gas tank to access the manifold bolts. Fuel line disconnected and it came right out. I'll rinse it out now that it's off. Manifold bolts
came off with no real issues. Some with a socket others with a open end and box wrench. Two studs unscrewed from the block, no problem I
have all new studs to reinstall. I'll reinstall everything later in the week. I need to modify by grinding a few wrenches to do the install. Man it's
tight in between the webbing. Removal was one thing but torquing them proper is another.
The head by number 4 is lightly pitted just as I expected from reading on this site. Nothing too bad a gasket will be fine. Total into it now is
about 1hour 15 minutes. Really a easy job with caveman tools.
Thanks for everyone's advise and the excellent reading on this site. I'll update more later, John

Well I got the manifold reinstalled last night. Things went pretty well. I turned on the gas on the fuel tank and let the sediment bowl and carb bowl fill up. I then drained the carb bowl and let the gas run awhile. I also did not remove the carb doing the manifold, just unbolted it and let it hang by the intake hose and governor shaft. It stayed very level.
Now my slight problem. The tractor always started right up with a little choke. 6 volt system, original. Last night it just cranked and did not fire up. It hit it with a small amount of ether and it started. Let it run awhile and it would restart. Let it sit awhile and it just cranked. Ether and started. Runs great at idle and throttling up and down once started. Test drove in all gears and runs smooth and excellerates through out the rpm range.
Question, what would cause it not to start up? Thoughts? Thanks, John.

Sounds a lot like fuel delivery , even though you didn't disconnect the carb it has moved about a little. Starting with ether is a giveaway for this problem . There is most likely some obstruction in the jet or needle ans seat . Try this trick , start it whichever way you can with the air cleaner disconnected, let it run at mid rpm or higher if you can put up with the noise . Take a rag and cover the intake of the carb choking it until it almost stalls , then quickly pull the rag away . The resulting rush of air into the starved engine does wonders for cleaning out grit . Do this three or four times . If that doesn't work a quick disassemble and clean might be in order .

Thank you chas in Aus. I'll try that. I do have all new Rubber intake hoses from the air cleaner to also install, but yet to do that. When I get them off and ready to install it would be a perfect time to try that out. Thanks