Toolcrib, I just did the service on my 2005, 990 that I bought used. It has the water separator/sediment bowl/filter at the tank. It then has another filter at the engine. My 990 is about 7 years old. I don't know how to find the exact date that it was manufactured. Maybe there is a way to do that on JD's website. Getting back to the subject the filters have never been changed on my 990. You can see in 2 of the pictures that the fuel filter at the engine still had the green paint around the top of it. It had 174 hours on it when I bought it. I bought the filters and O-rings. So this past Saturday I did the change out. You can see the pictures below. Brian had noted in an earlier post that the bowl could get brittle. Mine was not brittle however I wish that I had purchased a new one of these also due to its discoloring. I cleaned it out as best I could. There are some little narrow slots in the bottom of it that proved to be too difficult to clean completely. The other thing is that there is a red float inside it which I am guessing is suppose to float on the water if there is any water in the bowl. That I could not see before. I can at least see it now but it is still a little murky because of the discoloration of the bowl. In one of the pictures you can see the color difference between the old filter and the new filter. My guess here is that rust is probably the biggest discoloring factor. I looked down in the tank with a flashlight and it looks very clean. However the nozzel for filling the tank at the top inside of it is where you see some rust pits and most probably due to condensation. Also in an earlier post Brian had suggested a fuel additive that one should use with your diesel fuel. I went and purchased it and added it so hopefully this will help with any water in the fuel and also benefit the whole diesel system all the way to the injectors. You can find that complete thread here http://www.greentractortalk.com/forums/showthread.php?631-Fuel-Filter-change.
Rob
P.S. this thread that I put the link to was actually started by someone who had a 3720. My guess is that things are probably pretty similar on the 3520 as well.
Also there is one more post to finish up on the pictures.
Rob
P.S. this thread that I put the link to was actually started by someone who had a 3720. My guess is that things are probably pretty similar on the 3520 as well.
Also there is one more post to finish up on the pictures.