Analyzing Leads To Summer Maintenance

Our antenna (Mosley TA-34-XL) has been up for several years, first in Ohio and then here in Alaska. I packed the station up from 8land and put my beam into operation here a year or so after our arrival. Same feedline, same everything.

Lately the station has been having some issues from the tuner going out in my PRO to my AMP not wanting to work on 15 meters. And to top it off, I am seeing my beam is no longer in resonance where I had measured it oh so carefully a few years ago. Just like in the photo here, things are a bit blurry until you start the process of elimination.

Today I noticed an unusually high SWR on 20 meters which made me drag out my Analyzer. When I hooked up my MFJ-259B directly to the feedline leading to my beam, things became a bit clearer, kind of.
It's obvious that my antenna is no longer resonant at the bottom of 20 meters where I had left it. As seen in the photo above, it is now resonant well outside of the 20 meter band. This alone tells me it's time to plan some summer maintenance. What is and where could the problem be? Only a bit more summer time investigation will tell.

I have an external antenna switch that I run all of my antenna's to. I like them as it keeps my coax runs into the house at a minimum. Also, my feedline is getting old and is in need of replacement I'm sure. The antenna could have also moved from it's original measurements due to the extreme weather that hits this area. We get constant 55 mph wind gusts throughout the winter with gusts reaching 70 mph. I also see temperatures to -45F during the deepest and coldest months of winter as well. So many variables that could lead to problems. Routine maintenance here probably needs to be a bit more frequent. Either way, this aging station is in need of some work and although I tend to push radio to the side a bit during the summer months, this summer will need to be an exception. Now that the days are getting longer and the temperatures are beginning to warm, my operating will become much less. Summer may seem long but I find the window of opportunity here rather short. Summer seems so short in relation to winter, but that's life at 63 degrees north.