View Full Version : Yanmar 2qm keeps filling sump with water

10-29-2008, 10:55 AM
"blooming thing, we checked the head gasket, bought new elbow for exhaust, and now whenever i turn the engine over to bleed it up, the sump fills with water, any ideas, ive checked the water pump, it aint that...."

10-29-2008, 08:26 PM
"You have a 2QM20? The sea water pump is run off the front cover. If this seal leaks, you have 2 one for oil and one for water. Take the pump off and change the seals. May as well change the ball bearings too. You do not turn the engine to bleed, use the fuel pump lever. Is this unit fresh water cooled? Was there any chance of this engine freezing? Please confirm. What did you do to check the head gasket? Regards Ron"

10-31-2008, 06:03 AM
"(its a 2qm 20)ok, i think ive solved it, the exhaust outlet is too high, and when the engine is turning over to start, no exhaust gasses pushing the water out cause it to go back into the engine, so what ive done is to separate the water into its own outlet. the current exhaust outlet is way higher than the exhaust elbow (it is a newly fitted engine, not by me into a narrowboat) one thing ive noticed is that these yanmars are riddled with very very soft alloy, which allows for very easily broken threads....anyone got a spare fuel filter housing?, i found there are 3 leaks on this one, helicoiled the bleed and the return threads, only to overtighten (with my hand!!!) the thread on the bowl, cant helicoil this, so im going to take a couple of mms off the thickness of the flange on the bowl to allow the thread to bite a bit higher up, needs must! im on a jouney down the grand union, lost me phone, and need to get to the thames before the end of this month"