[TowerTalk] Issue with Tri-Band Yagi SWR

[K3SK]

I'm have an SWR issue with my Wilson 4 element tri-band yagi.  I started
with really bad SWR on 10 and 15 meters.  20 was better at ~2 to 1 across
the phone segment.  So I took it down to isolate the problem.  I took all
the traps apart and found no corrosion, arcing or other problems.  The traps
are a double trap in a single housing very much like Mosley TA-33 series.
Putting the antenna back together I found water in my balun so I replaced it
with a new 5KW 1:1 from DX Engineering.  I reinstalled the antenna to the
tower at 60'

On 20 meters everything is fine.  Good SWR and bandwidth.  15 meters SWR is
2.9 to 1 across the phone band.  10 meters is 1.5 to 1 and higher across the
phone band.  Can bad feed line cause these indications?  My coax is quite
old, but does not look bad from the outside.

Looking for any ideas or suggestions.

de K3SK