what should i do to fix it and how can that happen

 

If you actually got mud inside the crankcase, tearing the motor down for cleaning will be required.

What kind of machine is it, and how did you manage to get mud in it?

Anyhow, might be time to invest in a snorkle...

 

Whell it is a 2005 honda recon with mudlites and i thought that it would cross a part of the pond(when i walk across it i sink like 2-feet) and after that i just folowed the jeeps and cross anything they do

 

Were do i start[img]i/expressions/face-icon-small-sad.gif[/img]

 

did you get water or mud? either way you will have to split the cases and clean the top end. sounds like a mess.