impossible to get 2 wrenches on it. I was thinking of making an offset wrench someday. What I did was to take some PB Blaster and sprayed it into the cap and applied it to the nuts with an acid brush. Be careful and patient. Took about 4 applications soaking overnight and I was able to break the retaining nut using a small ball peen hammer and a center punch. You have to be patient not to destroy the nut if it doesn't move easy reapply PB. Once I had it free I used a stainless wire brush in my drill to clean the green tarnish from the nut and threads. Repacked it and tightened with a wrench that MaineSail suggested. The angle the wrench takes to engage doesn't do a great job in tightening it. It's not much tighter than hand tight. I've had no trouble with it after 2 seasons. I actually was worried I was not getting any water dripping yet the shaft has always been only slightly warm to the touch after many hours of motoring.
