you may have a lobe on the cam that is ground down or a valve spring or lifter problem on one side. does it make any noise like ticking or cracking? the Holley could be too big of carb also. what size is it and is it properly adjusted? the fluid on the fan is probably coolant. check for pin holes in the rad. if you can't find any holes, try blocking off the upper lower rad hoses, find an old rad cap and tap an air fitting into it. fill it with NO MORE than 20 psi of compressed air and see if you can feel any air coming out. as for the battery drain, good luck.