If there is dirt and water there should be a way to clean the fuel tank,
do any of you guys have any ideas?

 

Methyl hydrate will suck up the moisture/water (also known as gas line antifreeze).
How much dirt are we talking about?

 

Don't know how much, one of the mechanical where i take my Expy for
service said I got water in my gas tank which is causing my engine
to hesitate sometimes. Does that sounds right?
Where do I get Methyl hydrate?

 

Methyl Hydrate might be hard to come by where you are(Dominican Rep) It is also is used in fondue pots, so perhaps somewhere that sells cooking supplies would carry it. And I'm not positive on this, but I wonder if truckers don't use it to keep moisture out of their brake lines.