white smoke is water, blue smoke is oil, you have to figure out which, could be worn valve guides on that cylinder bank, that would give you bluish smoke. if it is water, you will see it on your eng. oil dip, milky looking if head gsk. bad & letting coolant into crankcase oil.
could be cracked ring, could go on and on, best way to test is a compression test, test dry, then wet, if you have one or more cylinders below acceptable compression, test, then add appx 1/2 oz. of engine oil or equiv. if compression comes up after wet test, rings are your culprit, if compression on low reading cyls. does not come up after wet test, your valves are the culprit. a cylinder leak down test will also seal the deal, you pressurize the ind. cyl. on its compression stroke(both valves closed) & if your gauge drops psi listen from where, through the carb will be int. valve, through tailpipe will be exhaust valve, from dipstick tube or oil fill cap will be rings, good luck, probably gonna be cyl. head related or you would have an oil consumption problem, (cracked ring will chew up more oil than worn valve guides)john