Mercruiser 3.0 (older) Leave hose off? Plugs out?

ChronoFish

Cadet
Joined
Oct 26, 2015
Messages
27
I have an older Mercruiser 3.0 that I recently got running (for several seconds) but not long enough to winterize. I've removed the 2 plugs on the port side (didn't find any on the starboard side) and removed the 2 large hoses. Lots of water was drained.

The inlets from the large hoses are pretty gummed up and I had a nice combination of clear, then rusty, then oilly water come out from the plugs. Manual says to leave the hoses off if the boat doesn't have a seacock which I don't believe it does. I'm pretty sure it's a seawater only cooling system.

I plan on doing a full cleaning/flushing of the cavities in the spring .. Id like to keep the hoses on to just keep debris (and critters) and moister from entering. What's the purpose of keeping the hoses disconnected? To that end, wouldn't it be better to reinstall the plugs in the spring too? (Or is that just keep from losing them?)

Did I miss anything obvious... This was my first time at it.

Thanks!
CF
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
42,568
I reconnect the hoses after draining.
I also leave all the plugs out and in the cup holder, but there is nothing wrong with reinstalling. If there left out and there happens to be some water behind a mud chunk, it will slowly seep out over time.

Either way I thing your fine with one exception

then oilly water come out from the plugs

Oily water is never good to see. May have another issue, check the oil pan for water
 
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