[C320-list] exhaust elbow question

[Bruce Heyman]

Jon,

Thanks for the research, will be very helpful.  

On the starting I've learned that for most engines and diesels in particular
the most wear to bearings, sleeves, rings.... is when the engine first
starts up.  The reason is that the lubrication system is not yet pressurized
so many parts are running without the film that protects them. 

Some people actually turn the engine over with the starter while holding the
engine kill knob until the low oil pressure alarm shuts of and then let the
engine start.  

Starting at full throttle and then cutting it back seems like it would be
pretty hard on the engine.  

I'm anything but an expert so interested in everyone's thoughts.

Bruce
Somerset 670 SoCal

-----Original Message-----
From: c320-list-bounces at catalina320.com
[mailto:c320-list-bounces at catalina320.com] On Behalf Of jonvez at comcast.net
Sent: Wednesday, October 04, 2006 5:02 AM
To: Allan.Field at comcast.net; C320-List
Subject: Re: [C320-list] exhaust elbow question

Koen,

I posted several questions related to the exhaust elbow as I was interested
in proactively replacing mine (my boat is in it's 8th season in salt water).

My confusion was whether the elbow was custom made by Catalina like the
muffler, or whether I could get it from a Yanmar dealer--than answer is
BOTH. Some hulls (with the Yanmar) had a custom elbow made by
Catalina...even though I suspected this was the case on mine, I couldn't
confirm until I went to a local Yanmar distributor myself. Even Catalina
couldn't answer this question....The good news is that if you do have a
custom elbow from Catalina, you can indeed replace with a stock Yanmar
elbow...The bad news is, you need to buy 3 pieces (for about $360 vs about
$160 for just the elbow). The Catalina elbow is a one piece elbow, whereas
the stock parts have a manifold, an adjusting screw connector and the elbow.
Once you have replaced with the stock parts, you will only have to replace
the elbow (top part) going forward....

As for time, Mr. Douglas had suggested 5-8 seasons is a good time to
replace. One suggestion on keeping the buildup under control from Mack
Boring is to start the engine at full throttle and bring it back to idle as
soon as the engine starts...This will blow a lot of the build up out and
presumably delay the inevitable...

Regards,

Jon Vez

-------------- Original message -------------- 
From: "Allan Field" <Allan.Field at comcast.net> 

> Koen - There are 2 concerns with the exhaust elbow. The first is that it 
> clogs over time and will impact engine performance. The second is that it 
> eventually gets pinhole leaks. Both happened on my previous boat. Trust me

> when I say that you don't even want to think about the mess you will have
if 
> the elbow gets a pinhole leak. The engine compartment fills with black
soot 
> that never completely goes away no matter how much you clean, clean,
clean, 
> and clean some more. 
> 
> I intend to replace my elbow prophylactically over the winter at about 500

> hours, change the hose to the aqua lift muffler, add a hump hose at the 
> muffler, and pull the muffler, send it back to Catalina, and have a 
> duplicate muffler made to sit on a shelf until when I need it. Again, you 
> don't even want to think about the mess if these parts fail. 
> 
> Allan S. Field 
> Sea Shadow - #808 
> Columbia, MD 
> 
> -----Original Message----- 
> From: c320-list-bounces at catalina320.com 
> [mailto:c320-list-bounces at catalina320.com] On Behalf Of Koen Bennebroek 
> Sent: Tuesday, October 03, 2006 9:05 PM 
> To: c320-list at catalina320.com 
> Subject: [C320-list] exhaust elbow question 
> 
> I seem to remember someone mentioning that the exhaust elbows on C320's
get 
> clogged and are recommended to be replaced every so often.. 
> My local mechanic, who will do the very first service on our boat soon (so

> we do not have experience either with him or with the engine 
> service in general), recommends we order the elbow and gasket from Perkins

> (I believe tadiesel sells them?) in advance to save time. 
> 
> Is this a good suggestion? We have purchased the boat used 2 seasons ago,
so 
> I have no idea what the history of this part is. 
> 
> Thanks for any suggestions, 
> 
> -Koen 
> 
> 
> 
>