[C320-list] Exhaust leak

[Paul Rickman]

Bob,

While doing chores today, I started looking around the Yanmar 3GM30F and found 
that breather tube you mentioned. 

It seems OK but strange that it has no hose end connectors. I remember replacing 
that hose a couple years ago because
it was split. I also checked a part on the back of the valve cover. It has
four bolts on the very back. All four of these bolts were loose, but one was 
very loose and appeared to have soot all 

over it. So, I've tightened all four of these bolts and we'll see what happens 
when the motor is under a load. 


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




________________________________
From: Robert E. Sloat <resloat at comcast.net>
To: C320-List at Catalina320.com
Sent: Fri, May 13, 2011 1:33:31 PM
Subject: Re: [C320-list] Exhaust leak

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