Agree with glacierblaze. Sometimes ear muffs might not give enough water pressure to really test it.
I bought a plastic horse trough from Tractor Supply Co. and it will accommodate my Honda BF200 trimmed down. It's handy to have if you want to change fluids off water so you can warm up the engines first.
I'm not very technical, you'll have to copy and paste.
Rubbermaid Structural Foam Stock Tanks, 150 gal. Capacity, 4245-00-GRAY
SKU # 222991999
Also, what Lsquared said about critters going into the pee hole is also common. Happened to me when I first bought my boat. I freaked out a bit, then took the smallest twig near me from a dead tumbleweed and poked it up in there as far as I could and voila, fixed problem immediately. I think because there is water residue in the line at the plastic grommet, it's a buffett call for a whole manner of wildlife.