Dearborn Interceptor Y block hesitation solved.
The engine was hesitating awefull bad on acceleration and stumbling, creating a lean condition in the carburetor as the "problem" turned out it was a timing issue with the centrifugal advance in the Distributor, To check this, move the rotor while still on the distributor and if it has play, and doesn't spring right back then it's the distributor, I bought a distributor, cap and rotor for 1957 (this should be the same year as your engine. Thunderbird with the 312 y block with four barrel carburetor to match my setup, worked like a charm, problem solved. Also while checking the Advance in the distributor, you want to check the timing chain, to do this put a socket on the front pulley and spin the engine, there should be no lag in response at the rotor to your turning the crank, if there is lag then the chain is stretched, also you timing mark will be 15 degrees BTDC. Also your points gap should be between .14 to .16 and your points dwell should be close to 28 degrees. Good luck all, I'm finally able to enjoy my boat!!!!
All information on the Y blocks can be found on this site here. enjoy.
www.ford-y-block.com/