Anybody know what the base material for the black plastic tank? Polyprop? Polyethelyne? Mine cracked under the battery and plan on heat welding it as adhesives do not bond to the olifin family of plastics.
I do not know which type of plastic is used to make the tanks but if I was in your shoes I would just replace the tank. Used parts can be found on ebay all the time and you will not have to worry about the crack leaking again down the road. What year and model is your tractor?