I was putting new coolant in my 4wheeler and i had to get the coolant out of the engine and i broke the gasket when i was taking of the water pump so i replaced it with cardboard and put sme sealant on top off that do you think it will hold

 

If it was the single layer cardboard that wasnt real thick, I have done it before in needy situations. The worst thing it can do is leak. If you used a good sealant and cleaned the gasket off first, you will probably be OK.