Fuel problem?

[cowsmowmygrass]

Mahindra 6500 with 225 hours

https://skydrive.live.com/?cid=932897728b6597e9&id=932897728B6597E9%21294&sff=1

Using off road diesel.
Condensation and/or dirty fuel is possibility. So is fuel filter or air filter block. Smoke color should be a good hint.

 

[LHO]

How do I change the fuel filters on a 1973 John Deere 820. Is there a diagram of the fuel system and directions for changing the filters?