544J start problem

All,

We have a 544J loader and have a problem with it on initial start

Fuel is good
Fuel lines are clean and good
The feed pump (not sure what its called but provides fuel to the main pump) is good
It is not sucking air
The main fuel pump has just been replaced
The engine compression is good
In warm weather
On initial start it turns over plenty fast but will not start
With just a touch of ether it will start and run fine
Even if you work it for a while, if you kill it and wait 30 seconds it will not start
There is not diesel in the oil

I do not know the details of the system well enough to know what might cause this....is there a cam sensor or crank sensor that could cause this? it just acts like the injectors are not pulsing or something like that....but why only until it starts...it is turning 250 it is not turning over too slow.

I appreciate any help you can give me.

mpolk