underwater hot water exhaust discharge

todd brinkerhoff · Post by **todd brinkerhoff** » Fri Oct 08, 2010 9:26 pm

I noticed the posting on the underwater exhaust topic, so I figured I would ask now. I purchased '91 10.8 meter express and it discharges the raw water exhaust water through a seacock by the v-drives, so the exhaust out of the thru-hull is straight exhaust gasses. Any idea why this was done. The only safety measure they have in regards to a failed pump is a hot water exhaust alarm, so I usually touch the hose prior to going out to make sure the water is pumping.

prowlersfish · Post by **prowlersfish** » Fri Oct 08, 2010 10:03 pm

Water is discharged with the exhust

RWS · Post by **RWS** » Sat Oct 09, 2010 5:42 am

The raw water circulates through the heat exchangers, then combines with the exhause gasses to keep the exhaust temp down.

The comingled mixture then leaves the boat.

RWS

todd brinkerhoff · Post by **todd brinkerhoff** » Sat Oct 09, 2010 6:24 am

That is all understood, however on my 10.8, the water is directed from the riser to a hose that discharges through the bottom of the boat. The actual exhaust gasses are discharged through another through hull on the side of the boat. So when you look at your exhaust outlet, there is no water. Wondering what they were thinking with this set up, because you can't tell if your raw water pump is working by simply looking at your exhaust outlet.

rbcool · Post by **rbcool** » Sat Oct 09, 2010 6:26 am

On mine there is a seperate hose that comes out of the top of the mufflers that shoots the water portion of the exhaust out through a big clamshell just above the waterline on the sides of the boat. The exhaust gases continue down through the bottom to a wild looking thing that looks like a huge pan flute. It's six round 2" tubes connected to each other.

RWS · Post by **RWS** » Sat Oct 09, 2010 6:49 am

Todd,

I've never seen a 10.8 with V drives.

I wonder if anyone here on this site has either.

This must be an amazing boat.

I imagine it's a really nice arrangement.

I think we would all really appreciate seeing some detailled photos of the entire layout and engine room too.

RWS

prowlersfish · Post by **prowlersfish** » Sat Oct 09, 2010 7:24 am

Some water maybe diverted but there is some going out with exhaust . if not you would burn up every hose on the exhaust in short order . you not see it because its partly below the water line or completely on the tri

todd brinkerhoff · Post by **todd brinkerhoff** » Sat Oct 09, 2010 7:56 am

I'll try to take some photos if I can figure out how to post them, but there is not a drop of water coming out of the exhaust. The owners manual stated that this set up was designed by Trojan for this boat. Its kind of a pain in the butt, because I am use to checking my exhaust outlet for water. So essentially, this boat is dry from the muffler to the exhaust outlet.

rbcool · Post by **rbcool** » Sat Oct 09, 2010 9:02 am

Try http://www.photobucket.com I just did it then put a link to my pics on my profile.

Just a thought... maybe the water removes enough heat from the exhaust to keep the gasses from toasting the final hoses.
Ron