Well, you don't want that stuff to ooze into the evap before it dries and I don't exactly know what the thing looks like shape,etc wise. You're going to have to remove it to fix it anyway, so take it to homedepot and ask them about the best way to finish the job. For this particular app, there might be something even better than jbweld. You most def don't have to replace the unit. Good luck.