[qcj]

Thanks Steve. That is what I needed. The reason for all this is in my box of parts that came with the coach was two fuel filters that was marked for generator. #3390 I believe. They were small, the size of the oil filter, and looking in the manual there was no notification for the large filter with the water separator.
My Cat. engine had a primary and secondary fuel filter. Wander why Detroit has only one.