I had not been out to the equipment pad in awhile. When I did, this is what I found:
I thought at first it was corrosion, but when I took the clamp off and examined it more closely, I would say it was a salt and/or calcium buildup. There appeared to be no damage to the metal itself. When I cleaned the clamp, the black coating came off and I could see that the buildup started under the coating and caused it to peel off. You can see in the pictures that the filter housing itself was damp around the clamp. Apparently water had been seeping through the seam for a long time. I did not notice any leakage the last time I cleaned the filter a few months ago.
I took the filter apart and cleaned it all out and inspected the o-ring. I did not see any cracks or damage. It is only 4 years old. I put it all back together and I have been watching it for a few days. I don't see as much dampness on the filter, but it looks like there is a little bit in the area around where the clamp hinges are located.
Any idea what could have caused this? Clamp too tight or too loose? We have had up and down temperatures for awhile - Highs in the 70's then down to highs in the 30's then back again. Could that have had anything to do with it? Does the clamp need to be replaced now that the metal is exposed?