Welcome to CEG!
I'm not sure I would rebuild the bottom if it has been open to the weather.
Originally posted by Jared:
Now I know some of you may say dont do that due to you should match the rod and cap, due to square bores, ect.. and itll never run right. Well I've done this to a lot of motors and they all turned out fine for me.
You cannot mix these rods and caps, due to the fact that they are "cracked" and not machined. If you purchase new ones they will come together. 
