Re: Can flushing cause upper seal to leak?
Right, the oil that drains from the exhaust cavity is a dark brown to black looking oil. Mix it with water and it's a dark milky color. <br /><br />If it's got ya' worried, drain the lower unit oil and check for water. Rig a bicycle pump to the the vent plug or drain plug in the lower unit and dump it into a garbage can full of water. Put some air pressure into the lower unit and watch for bubbles. Won't take much air to show any leaks so don't over do it.<br /><br />The test is easy to do and will give you some piece of mind. Keep us posted....thanks.
