Hello all, Thanks in advance for your input. I recently installed a new Yanmar 3YM30 in my new to me '88 legend 37. After the warranty required sea trial, the supplier said that the original Hunter exhaust design was inadequate to prevent cooling water from entering the engine while heeling or in rough conditions. He wants to raise the mixing elbow as much as possible and add a waterlock muffler. I did not see a similar thread in a forum search. Is this familiar to anyone? Thanks again
exhaust modification?
- Thread starter rbrtnaylor
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Is that what caused your previous engine to die? I have not heard about any such issue over the years. Is your muffler built into the hull?
Yes the issue is a familiar one.
Consider this to start with - http://www.yanmarhelp.com/i_exhaust.htm. See if this matches/approximates your supplier's version for your exhaust layout.
Charles
Consider this to start with - http://www.yanmarhelp.com/i_exhaust.htm. See if this matches/approximates your supplier's version for your exhaust layout.
Charles
The PO had pulled the original engine prior to my arrival. I had it checked out and both the block and head were cracked. Not sure of the cause. There is a stock Vernalift muffler inline aft of the fuel tank. The supplier seems to be too busy to do the mod, so I am preparing to do it myself. The plan is to remove the mixing elbow, hard pipe 12" to starboard, then 12" up, reinstall mixing elbow at that point, exhaust hose down to new waterlock muffler and then connect to existing hose. Not a major project if I can source the SS or bronze pipe. I get the concept of protecting the motor, and have to wonder about other hydrolocked engines caused by the design.
For SS threaded pipes and fittings try Grainger.com. Not the cheapest but very easy to deal with.
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