Damage to filter bags?

I am going to mix wmo with my fuel in my duece so I bought some filter bags and was wondering if a little water inthe used oil will hurt the filters and if it does can the bags be washed some how and be reused.

Just what kind of filter bags are we talking about? If they use a paper filter element then water will saturate the paper and not let anything flow through. *This also works with the paper element in-line fuel filters; so if you have moisture in your fuel tank, plan on changing the filter out when it stops flowing fuel. Can often be the source of that elusive fuel starvation problem*.

Thy are the felt filter bags that are being used for filtering used oils.

I wasn't sure they were designed to be reused. But if it's cloth and not pressed felt, they should be cleanable. Try it on one and if it turns into soggy dryer lint you'll know that they're a one shot deal.
Gonna be a messy operation though; not something I'd run through the family Maytag. Let the bags drain as completely as possible by turning them inside out over a drain container. Trick is then to rinse the bag by flowing cleaning solution (solvent, detergent, whatever?) through the felt from the cleaned oil side to the contaminated. That'll drive the sludge out without pushing it further into the cloth material. And of course, dispose of the sludge properly.
Good luck.

Don't forget to drain the water seperators often. And if the trucks sits for a few days you can pull the drain in the fuel tank untill fresh fuel comes out.

Good point Ken. I've become a fan of water seperators for both fuel and air systems since I started the baby HEMTT project. The problem with big fuel tanks is that moisture will collect inside on tank walls regardless of that other measures you take, so draining off the condensation is a good idea. A pain in the a$$ but then so is a rusted out fuel tank. Keeping a full tank of fuel will cut down on the available space for the dew drops to form but that would take mortgaging the farm at today's prices.

I'd suggest turning the filter bags inside out and washing them real well with straight Simple Green (100%) and flushing well with clear water. That stuff works wonders on waste engine oil. After the Simple Green treatment, washing the filter bags in the family Maytag on "delicate" cycle ought to restore them to near new condidtion (although the McMaster Carr bags are pretty cheap to begin with!).

What kind of filter bags are yall using. I am trying to get started with Wmo