[C38] Exhast Mixing Elbow?

[Max Soto]

Hey Tom,

I haven't heard this one before...
Wasn't aware that the hotter the water on the exhaust, the
better...I thought that the channels on the elbow were for cooiling it, not
for the elbow to heat the water.. I've been thinking about it but can't come
with the right answer..Why is that recommended????????

I made mine four years ago  out of stainless pipes ( chinese stainless, so
they better than galvanized and cheap) and  made an insert on the elbow that
comes about  2" lower than the barbed fitting for the hose, so I was kinda
worried about the top part of the hose melting, but so far, so good after
1600 nautical miles.....

I'm also planning to make another one for the new engine, but I'm taking it
one step at the time!!

Regards, Max

2011/7/24 tdtron at earthlink.net <tdtron at earthlink.net>

>
> Hello David,
>
> Those cast iron elbows self destruct and eventually need replacing.  At
> this juncture, you probably only have three viable options, either replace
> the elbow with another like the original or fabricate one from stainless or
> standard steel fittings.  If you decide to go the stainless route using
> stainless fittings, expect to spend some real money.  The dairy and other
> food industries use threaded stainless fittings but you won't find them at
> your local plumbing supply.  If you fabricate an elbow from stainless pipe
> instead of fittings, it will be cheaper but with more labor involved.  In
> any case, there needs to be a cooling passage to preheat the hot water
> discharged from your heat exchanger before the water actually enters the
> exhaust.  With either threaded fittings or fabricated stainless pipe you
> will have to weld a pipe to the side of the elbow to preheat the cooling
> water before it discharges to the exhaust.  The hotter the water, the
> better before it joins the exhaust.
>
> As you can see, the fastest, easiest and cheapest way to fix the problem is
> to just replace the #$%^& cast  iron unit.  By the time the cast iron units
> fail, they are usually very brittle, thin, and the cooling passage
> mentioned above is clogged from corrosion and scaling.  I have removed cast
> iron elbows that didn't look very bad but crumbled in my hand when I
> removed them.  Cast iron sux but it is cheap, too bad it isn't also
> inexpensive.
>
> A third option is to make the elbow from standard plumbing fittings but you
> will still have to make the heat exchanger preheater for the water like
> with the stainless option.  This is by far the cheapest option but like
> cast iron, it will be only temporary until the steel rusts out.
>
> I have seen people make elbows from pipe fittings with just a threaded barb
> to allow the water into the elbow below the 180 degree bend without any
> heat exchanger passage and as far as I know, they had good success but
> Universal thought the heat exchanger passage was a good idea and they are
> smarter than I am so use your own judgement on this issue.  The heat
> exchanger passage definately complicates things.
>
> I have a weld shop and I planned to build a stainless exhaust from the
> manifold to the rubber hose but I ended up selling my 38 before my exhaust
> failed again.
>
> Good luck,
>
> Tom Troncalli
>
>
>
>
> > [Original Message]
> > From: <david at dlrfilms.com>
> > To: Catalina 38 Listserve <listserve at catalina38.org>
> > Date: 7/24/2011 9:47:44 PM
> > Subject: [C38] Exhast Mixing Elbow?
> >
> > Next stop on the tour of my engine, the exhaust mixing elbow has a crack
> > in it and both water and exhaust are coming out. I've never used JB Weld,
> > but thinking this might be the time to learn.
> >
> > Of course the elbow and nipple connecting ot the coolant tank look like
> > they haven't been moved since the boat left the Catalina factory. I've
> > been putting Liquid Wrench and PB Blaster on at the begining of each day
> > and hope the heat and vibration is working it in.
> >
> > Have been having some AMAZING trips. One thing I've learned is that if I
> > have happy people on my bow, I don't even mind having the engine on, but
> > sailing is still best!
> >
> >
> > _______________________________________________
> > Listserve mailing list
> > Listserve at catalina38.org
> > http://catalina38.org/mailman/listinfo/listserve_catalina38.org
>
>
>
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>



-- 
Max Soto
C38 #198 ESTANCIA
Puntarenas, Costa Rica
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