Kubota GF1800 diesel not starting

[RandomUser1111]

I have a Kubota GF1800 with a 3 cylinder diesel engine.
This is not starting but will catch briefly with starting fluid.

There is plenty of fuel going to the injector pump but very little coming out.
In general is an injector pump something that can be taken apart and cleaned out, or is it best to just replace it? Prices seem all over the place for a replacement, anywhere from $450 to $1200.

I have not worked on a diesel before, is replacement or rebuild of this something only a shop could do?

 

[RandomUser1111]

Still working on this problem but I think the injector pump may not be bad now. I took the lines off it and all three outlets were shooting high pressure fuel in a sequential pattern.
I may have just had bad diesel so I am draining everything and replacing with fresh fuel.

 

[bertsmobile1]

Very good chance it has gone off over winter .

 

[mcspeed]

So what was the issue? Curious to know.