[C320-list] Exhaust leak

[Robert E. Sloat]

Paul-I assume your hull has a Yanmar 3GM30F, so check the breather tube at 
the back of the engine which is attached to the back of the valve cover and 
has a rubber hose going to the intake manifold.  It carries exhaust or other 
blow by back to the engine from inside the valve cover.  If there is a loose 
fitting or leaky hose there you will get blow-by venting into the engine 
compartment which has an exhaust-like smell.  Also check the air breather 
filter to make sure there is no blockage.  You indicate engine compartment 
has smoke near the front which is not where the breather is, but smoke is 
very mobile.  A long shot is a cracked exhaust manifold or leaky exhaust 
manifold gasket which would be on the right side of the engine.

If you turn off the engine and open the drain on the lift muffler any 
accumulated water will come out.

Bob Sloat
Savannah 894
----- Original Message ----- 
From: "Paul Rickman" <ilove2sail at verizon.net>
To: <C320-List at Catalina320.com>
Sent: Friday, May 13, 2011 8:20 AM
Subject: [C320-list] Exhaust leak


Some of you have had issues with the Catalina muffler. As I recall
each one detected a leak because you found water around the muffler,
and therefore, found a crack. I have a new gasket on the manifold,
a new exhaust hose, and a new Catalina style (riser where the water
gets injected into the exhaust). I have removed the muffler and
could not find any cracks and I do not detect any water around the
muffler. I have removed the muffler drain and replaced it with a bolt
plug (the old drain was leaking exhaust only, no water). After all
this, I still smell exhaust in the master cabin. I can also see exhaust
smoke in the engine compartment, on the sides, on the motor,
and on the forward cover - not so much on the aft cover and next to
nothing on the muffler. All connections are tight. My next move will be
to remove the muffler, fill it with water to see if it leaks.

Any ideas???

Thanks,
Paul
Affinity 657
Bay Bridge Marina
Chesapeake Bay, Maryland