Need Help with a model 21-six-49 buick

[Guest buick1921]

My husband is trying to get this 1921 Buick model 21-six-49 running. It will start up in the morning, he had it running for about 45 minutes at a high idle and got the temp up on the motor then turned it off and cannot get it started again.

He has gone through the carb it is not vapor locking. Two of the cyl are low on compression, spark plugs are running black with one wet plug. Everything is set the way the book says, everything is clean and operating. It has an electric fuel pump that is pumping at 2 pounds of pressure.

Any help will be appreciated.