The pump advances when you open the throttle, they start way better full open. I learned that JD's are the opposite, they advance til it gets oil pressure, and giving it any throttle you lose the advance and they start like crp.
But it should have fired off with the ether, if you shot it in with the air filters out.
If there was dirt in the housing around the air filters, it could be the engine is damaged.
You are getting good flow out of the fuel tank?