My Beamer is using slot of water but shows no signs of a radiator leak

Check the hoses nearest the bulkhead, sometimes they split and you can't see the leak because it's below the hose and running off your engine or bulkhead. If a hose is split, don't pay a fortune getting a new one. use copper or plastic pipe and a couple of jubilee clips after you have cut out the damaged peice and rejoin the hose.

Has it been run hot lately?do you have water or coolant in your oil? pull the engine dipstick to see. do you have oil in the radiator? do you see coolant coming from the exhaust? these are all signs of blown head gasket. unexplained useage of coolant with no apparent signs of leakage usually means that coolants going trough the engine and out the exhaust system.smell bad when idleing in enclosed space? unexplained smoke coming from tailpipe when weathers warm? water residue dripping from tailpipe after the engines warm? i've given you most of the signs of a blown head gasket,which is what you requested, using alot of water with no sign of leakage. if no water in the oil,no oil in the water, then the leaks into the exhaust and out the tail pipe. you can do this, remove the ant-freeze from engine, then apply nanno technology[auto zone] water only added to engine. follow directions on 1quart bottle. this has worked for me several times.[for blown head gaskets that leak into exhaust] it's new technology that's new to the automotive industry. 1 quart costs $20.00 considering how much it costs to replace a blown head gasket that's only leaking into the exhaust sysytem,that's worth a gamble l to me. i've seen it work myself.