[C38] C38s with Yanmar exhaust elbows

[Tom T.]

I have to agree with Dave McCarthy about the carbon buildup on diesel
exhaust systems.  All engines hate to run cold but diesels particularly.

When we were close to our final destination we would make it a point to
crank up and motor sail or drop sails and motor the last couple of miles
with at least 1500 rpms to completely warm our engine to remove
condensation in the engine oil and clean out the exhaust carbon while at
the same time heating our hot water tank for our hot showers at the end of
the day.  The cleansing benefits of a hot engine don't really start to work
until after reaching full temperature under a load.

After many years, our exhaust was still clean and our engine oil never
showed any signs of moisture.  

Tom Troncalli




> [Original Message]
> From: D McC <cat38skip at yahoo.com>
> To: Catalina 38 Listserve <listserve at catalina38.org>
> Date: 2/26/2010 9:21:24 AM
> Subject: Re: [C38] C38s with Yanmar exhaust elbows
>
> We had a similar loss-of-power problem on our previous boat with a single
cyl Yanmar. The exhaust was reduced to less than 1/8" due to carbon
buildup. This was a common problem for a number of boats in our marina. The
run from the slip to sails up was less than 10 minutes. The mechanic said
that if we did not run the engine at temperature for at least as long as it
takes to warm it up, we would continue to have carbon build up problems. I
don't know if this is the issue with your engine, but longer run times
seemed to solve our problem. 
>
> Dave McCarthy
> C38 #148 - Pretty Lady
> San Francisco, CA 
>
>  <><><><><><><><><><><><><><><><><><><><><><><><><><><>
>
>
> Common Sense is a rare gift from the Gods.
> Most people have only technical training! 
>
>
> <><><><><><><><><><><><><><><><><><><><><><><><><><><>
>
>
> The gods do not deduct from man's allotted span those hours spent in
sailing.
>
>
>
> ----- Original Message ----
> From: Phil Gay <eyriepg at comcast.net>
> To: Catalina 38 Listserve <listserve at catalina38.org>
> Sent: Thu, February 25, 2010 8:43:25 PM
> Subject: Re: [C38] C38s with Yanmar exhaust elbows
>
> I just replaced the exhaust elbow where the water is injected to the
exhaust
> on my 1996 Yanmar 3GM30.  The engine ran well before but I did it as
> preventative maintenance after 14 years of service.  I expected to see a
> plugged casting but it was really clean.  I plan to keep it for a spare. 
I
> don't understand why some clog and others don't.
>
> Phil Gay
> C38 049 Que Linda
> Everett, WA
>
> -----Original Message-----
> From: listserve-bounces at catalina38.org
> [mailto:listserve-bounces at catalina38.org] On Behalf Of Robert Miller
> Sent: Thursday, February 25, 2010 3:18 PM
> To: larrypi at linkline.com; 'Catalina 38 Listserve'
> Subject: [C38] C38s with Yanmar exhaust elbows
>
>
> I was gradually losing power from my Universal 5424 diesel.  Last week I
> took her out and was only able to maintain 1700 rpm at full throttle. 
With
> visions of a new engine haunting me I called the legendary Alfredo who is
> one of the best known diesel mechanics in San Diego.  He ran the engine,
> checked out the injectors and said "your engine is fine."  "It's probably
an
> exhaust restriction."  He pointed to the Yanmar elbow and said that they
are
> prone to clogging.  20 minutes later he had the exhaust system removed and
> broke the elbow with a hammer.  What had previously been a 1 3/4" passage
> was now completely clogged with carbon with two passages less than 1/8" in
> diameter.  He is fashioning a new pipe system minus the elbow and will
> install a new exhaust flange.  He will be back next week to install it.  I
> will let you know how it works out.  If anyone has one of those elbows and
> is losing power, check it out.
>
> Bob Miller
> "Bolero" #113
> Southwestern YC, San Diego
>
>
> _______________________________________________
> Listserve mailing list
> Listserve at catalina38.org
> http://catalina38.org/mailman/listinfo/listserve_catalina38.org
>
>
> _______________________________________________
> Listserve mailing list
> Listserve at catalina38.org
> http://catalina38.org/mailman/listinfo/listserve_catalina38.org