Water Muffler?

[Don Crowther]

HI
In searching though the archives I have not found much info. on water mufflers.
It would appear that my boat has one I think.

When I was following the exhasut pipe from the elbow on the back of my Yanmar. I noticed that one rubber hose connected to a pipe (lets call lit the inlet) in front of my fuel tank and right beside it was the outlet that continued out to the back of my boat.

What about winter maint.? I havn't seen anything in any of my manuals

Could anyone explain how a water muffler works and is there any maintenance to be done on it? Will it drain as the boat is lifted out in the fall?
Thanks
Don
Hunter 31 83-87

 

[Stu Jackson]

Try here: http://www.centekindustries.com/product_descriptions.html

 

[Warren Milberg]

Most likely you have the Yanmar 2GM20F or 3GM20F with a water-lift muffler. See this site for a pretty good description of how they generally work:

http://www.practical-sailor.com/marine/waterliftmuffler.pdf

Unless you run your engine dry in preparation for a freezing winter (not recommended, at least my me), some sea water will remain in the water-lift muffler. When you run anti-freeze into your raw water cooling system when winterizing it, when you see anti-freeze coming out the stern and shut off your engine, you will also be protecting whatever water remains in the muffler. Hope this helps.

 

[Don Crowther]

Thanks Warren

That's the answer I was looking for. I winterized the engine last fall using your method and everthing worked out fine. I just didn't understand how the muffler worked.
Thanks again Stu and Warren for the quick replies
Don

 

[Steve Dion]

The Hunter 31 has a built in muffler. I would assume that when you pump the antifreeze through the raw water side of your engine, the antifreeze will protect the muffler from freezing!