Dock Wheels - Thru Rod Needs an End Cap

[fishlips]

We have a standard 18' dock with the old, flat car tires on it. I pulled off one of the old tires to see if the new style, molded plastic tires would fit and ran into a small issue. The 2" pipe that goes thru the center of the tire is exactly flush with the hub on the molded, plastic tire when I put it on, so I have no way to secure it using a cotter pin. I'm assuming that others have ran into this as the dock style is very common (I think they are made in pelican rapids...). There must be some type of end cap that can be purchased to secure the molded tire on there, but not sure. Thanks for the assistance.

[solbes]

What I did with my boat lift was to buy 1 1/4" or 1 1/2" Galvanized pipe at the old Farm and Fleet. And then bought a flange fitting to cap the pipe. Fit just about perfect and holds the wheels on the pipe.

Can you just get a longer galvanized pipe and buy the appropriate size flange fitting?