American Standard Oil furnace model ACD 603 pump stuck and won't turn. What is the equivalent for a Sundstrand 1298 100 3 that I have.

I'm not familiar with that Sunstrand number but I presume it is a 'J' model with 8 bolts holding the strainer cover on. If this is the case, you could replace it with an A1VA-7112. You would also have to replace the coupling between the motor & the pump since the pump shaft is shorter & smaller.

Hey Grady thanks for the response, the pump is very old could be original where you able to get pump number by the unit model ?

No, I was not but if it is the burner I think it is, the A1VA-7112 will work. A clear picture of the burner would certainly help.