After taking some hull damage, our boat was hauled out for the winter in late August. From that time until this past weekend, the engine has not been started (late model A4, Moyer rebuilt with a Moyer water pump). Shortly after the haulout, I did a pressure flush on the engine, in preparation for winter layup.
Hull repairs and painting having been completed, I went this weekend to winterize the engine. Upon pulling the thermostat, it appeared that there was no water whatsoever in the engine - at least the thermostat well was bone dry. This didn't surprise me, as I expected most or all of the water had drained out of the drain holes in the course of the pressure flush.
I started the engine up, and ran it a bit to warm the oil, in preparation for an end-of-season oil change, before adding antifreeze and fogging with MMO. I noticed water leaking out of the bottom of the water pump. On closer inspection, it appears (though I can't be sure - visibility is limited) that the water is dripping out of the back plate of the water pump. There still seemed to be plenty of water running through the engine and out the exhaust port on the stern, but I'd call the water leaking from the pump a fast drip, at idle. I'm sure it would be heavier with the engine in gear and at cruising speed.
My plan is to pull the pump before next spring, install a new impeller (which is probably due anyway - got about 250 hours on the old one) and re-seal the back plate. My understanding is that this pump uses an o-ring, not a flat gasket, on the back plate.
My question is, what would have prompted this pump to begin leaking under these conditions. Have not had any trouble with it over two seasons of fairly hard use. Could the o-ring deteriorate just from sitting there dry for a month and a half? Any other thoughts?
As always, thanks for the help.
Jesse Delanoy
s/v f/k/a Agape
Baltimore
Hull repairs and painting having been completed, I went this weekend to winterize the engine. Upon pulling the thermostat, it appeared that there was no water whatsoever in the engine - at least the thermostat well was bone dry. This didn't surprise me, as I expected most or all of the water had drained out of the drain holes in the course of the pressure flush.
I started the engine up, and ran it a bit to warm the oil, in preparation for an end-of-season oil change, before adding antifreeze and fogging with MMO. I noticed water leaking out of the bottom of the water pump. On closer inspection, it appears (though I can't be sure - visibility is limited) that the water is dripping out of the back plate of the water pump. There still seemed to be plenty of water running through the engine and out the exhaust port on the stern, but I'd call the water leaking from the pump a fast drip, at idle. I'm sure it would be heavier with the engine in gear and at cruising speed.
My plan is to pull the pump before next spring, install a new impeller (which is probably due anyway - got about 250 hours on the old one) and re-seal the back plate. My understanding is that this pump uses an o-ring, not a flat gasket, on the back plate.
My question is, what would have prompted this pump to begin leaking under these conditions. Have not had any trouble with it over two seasons of fairly hard use. Could the o-ring deteriorate just from sitting there dry for a month and a half? Any other thoughts?
As always, thanks for the help.
Jesse Delanoy
s/v f/k/a Agape
Baltimore
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