Raw water discharge

Terry Cox · May 9, 2015

Sea Water Discharge

Hi Tim, both of our sea water discharge through hulls (main and generator) are above the water line by about three inches. That way it is easy to tell cooling sea water is flowing properly. Perhaps Marlow-Hunter can explain why your model is below.

Ralph Johnstone · May 9, 2015

Tim22 said:
One of the things that has bothered me about the Hunter is the under water discharge of the engine cooling water which makes it difficult to determine if the cooling circuit is working properly.?

The underwater discharge is for silent running when sneaking up on submarines :Liar:.
And yes, it's impossible to tell if there's sea water flowing or not, regardless of what the pundits around here claim. Wet bubbles vs. dry bubbles coming up through the surrounding sea water ........... now there's a real contrast for you

.

Tim22 said:
This started me wondering if there was any reason the discharge could not be moved to above the water line. Any thoughts on the pros or cons?

I would strongly advise against moving the discharge above the water line. Nor sure what they used for the hose connection within the hull but it's pretty solid looking and for what it does, it better be. You're looking at glassing in the same insert for your above water exhaust connection which should be great fun in such a confined space :bang:. Sounds like a lot of work.

A far easier and better way of monitoring your raw water discharge is an Aqualarm raw water flow switch as first mentioned in reply #9 of this previous posting:

http://forums.hunter.sailboatowners.com/showthread.php?p=1179176&highlight=flow switch http://forums.sbo.sailboatowners.com/showthread.php?t=168217&highlight=flow+switch&page=2

Rick486 · May 10, 2015

Ha! Funny story here. When I purchased my 44DS in 2007 new I noticed the engine exhaust was below the water line. I did not like that for reasons articulated above. When I questioned the dealer he told me that was the way they were being built. So I went on a tour of as many boatyards as I could think of (it was was Winter) and I found no consistency in placement of the exhaust. Some above the WL, some below. So I discussed this with the dealer and he agreed to move the exhaust up about six inches. No big deal. Everybody happy. I think what Hunter was (is) trying to do is eliminate CO in the air. If you look at their powerboats all the exhausts are underwater for the newer models.

seadaddler · May 10, 2015

Temp Gauge

Why not add a temp gauge and can find info on doing so here
in search.
All it is is adding a tee in the hosing close to where it comes out of the engine with a sending unit and adding a gauge at the helm.
Plenty of info here in the search.
My exhaust is just barely above water line but added a temp gauge at the helm
and this way it gives a better hint if anything going wrong like the sea water impeller or clog or anything.
Nick

Bill Roosa · May 10, 2015

I've heard of folks adding a small diameter line off the outlet side of the raw water pump and dumping that overboard at some visible location. Serves to verify that raw water is in fact flowing. FWIW

Ken13559 · May 10, 2015

Bill Roosa said:
I've heard of folks adding a small diameter line off the outlet side of the raw water pump and dumping that overboard at some visible location. Serves to verify that raw water is in fact flowing. FWIW

Good idea

Ralph Johnstone · May 10, 2015

Hmmmmmmmmmmmmmm ................

Bill Roosa said:
I've heard of folks adding a small diameter line off the outlet side of the raw water pump and dumping that overboard at some visible location. Serves to verify that raw water is in fact flowing. FWIW

........................ gotta take a second look at that one.

Yes, a small T'd line just downstream of the raw water pump will show pressure but that doesn't mean the heat ex. isn't plugged or the infamous mixing elbow isn't plugged with corrosion products. No cooling water getting through there.

If you T a small line off the 2" dia. exhaust hose line after the heat exchanger and mixing elbow, you're not going to have much pressure and nothing meaningful is going to come out of the tell-tale hose.

Oh well, back to the drawing board .......... or take the easy route and install a flow switch.