Catalina 34

General Activities => Main Message Board => Topic started by: Noah on October 12, 2020, 12:59:02 PM

Title: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Noah on October 12, 2020, 12:59:02 PM
I have all the aft spaces open/cleared with bulkheads and water tank removed. While doing repairs on my below deck autopilot (a story for another day) I discovered my exhaust hose is cracking and needs to be replaced. No leaks yet. But I will do it now while "in there". Does it make sense to replace my exhaust elbow and riser at the same time? Riser and elbow are probably original, but still "working" with no leaks. However, I know they will fail sooner than later. Any reason to preemptively do them now at same time as hose? Opinions requested, please! Due to virus restrictions I am planning to do this work solo. At least that's my plan. Also, I have a big Racor 500 turbine fuel filter under the head sink that will need to be removed to get access through there. Joy!
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Ron Hill on October 12, 2020, 01:44:26 PM
Noah : Look at my Mainsheet tech note article on replacing the exhaust hose w/pictures.
I'd leave the present riser in place and then replace when it starts to leak.  The main reason for riser replacement is because the weld at the raw water nipple starts to leak.  I finally figured that out and corrected it by removing/replacing the stuff wire reinforced hose with nylon reinforced hose (from the anti syphon valve to the nipple).

A few thoughts

Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Stu Jackson on October 12, 2020, 02:12:52 PM
Noah, one has no relationship to the other.  I redid my first of a few exhaust risers soon after we bought our boat when it blew out, say around 2001 or 2.  It wasn't until 2015 or so that we redid the exhaust hose to the transom (written up w/a link in the 101 Topics).  A recent tech note on replacing my muffler has some tips & tricks on the riser.
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Roland Gendreau on October 12, 2020, 06:01:20 PM
The riser on my engine failed with no notice 2 seasons ago, and my boat is the same vintage as yours.
So my opinion would be to either replace it while you have the boat down for the exhaust hose project, or plan to do it another time that is convenient.   I should have done it as a winter project rather than lose a couple of weeks in the summer.



Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Gint on December 28, 2021, 08:05:14 AM
Quote from: Ron Hill on October 12, 2020, 01:44:26 PM
Noah : Look at my Mainsheet tech note article on replacing the exhaust hose w/pictures.
I'd leave the present riser in place and then replace when it starts to leak.  The main reason for riser replacement is because the weld at the raw water nipple starts to leak.  I finally figured that out and corrected it by removing/replacing the stuff wire reinforced hose with nylon reinforced hose (from the anti syphon valve to the nipple).

A few thoughts

Hi Ron, I'm fairly new here and do not know how to find the Mainsheet article you are referring too. Could you assist with a link?
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: karista on December 28, 2021, 08:55:21 AM
Noah
My boat is the same age as yours. I would recommend that you also replace the riser, mine was replaced about 6 years ago as it started leaking fumes at the welded nipple. I purchased the new riser from Catalina Yachts not CD.
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Noah on December 28, 2021, 09:01:46 AM
Guys- that was a 2020 post of mine. I only replaced the exhaust hose at that time and left the riser alone for "another day". So far, that day has NOT come. No riser problems so far (fingers crossed).
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Ron Hill on December 28, 2021, 02:50:18 PM
Guys : The early C34 (1986 thru mid 1987) exhaust risers were made of black pipe.  Then Catalina changed over to stainless.  The stainless risers usually fail at the welded nipple for the raw water mixing with the hot exhaust gases. 

To prevent that nipple weld cracking - I recommend that the new risers have an added stake weld in the inside to add strength to the nipple weld on the outside.  I also recommended that the wire reinforced exhaust water hose from the anti syphon valve to that nipple be changed to a nylon reinforced hose.  That way all engine vibrations would be dampened by the more flexible nylon rather than the stiff wire hose!!

A few thoughts
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Stu Jackson on December 28, 2021, 03:15:14 PM
Quote from: Gint on December 28, 2021, 08:05:14 AM


Hi Ron, I'm fairly new here and do not know how to find the Mainsheet article you are referring too. Could you assist with a link?

Gint, Ron repeatedly tells us that he wrote it but never provides links.  First, he HAS written it!  He's our resident guru on C34 systems (except electrical - he'll be the first to tell you that!)  :D  He will never give you a link, dunno why.

So, here's how to find whatever he's telling you to go find:  THE KNOWLEDGEBASE.

https://c34.org/bbs/index.php/topic,3362.0.html

Download the Excel spreadsheet.  On the bottom are three tabs:  Introduction, All Articles, FYI-Categories.  Click on All Articles.  Then, use ctrl F (find) and enter a subject, which will usually get you a number of hits and the links are in the G column, right there for you.
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Gint on December 29, 2021, 07:18:50 AM
Quote from: Stu Jackson on December 28, 2021, 03:15:14 PM
Quote from: Gint on December 28, 2021, 08:05:14 AM


Hi Ron, I'm fairly new here and do not know how to find the Mainsheet article you are referring too. Could you assist with a link?

Gint, Ron repeatedly tells us that he wrote it but never provides links.  First, he HAS written it!  He's our resident guru on C34 systems (except electrical - he'll be the first to tell you that!)  :D  He will never give you a link, dunno why.

So, here's how to find whatever he's telling you to go find:  THE KNOWLEDGEBASE.

https://c34.org/bbs/index.php/topic,3362.0.html

Download the Excel spreadsheet.  On the bottom are three tabs:  Introduction, All Articles, FYI-Categories.  Click on All Articles.  Then, use ctrl F (find) and enter a subject, which will usually get you a number of hits and the links are in the G column, right there for you.

Awesome! Thank you so much Stu, I appreciate you. I got loads of projects to keep me busy and this forum is gold. Thanks to you all :)
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Ron Hill on December 29, 2021, 02:10:16 PM
Guys : The information is out there in those old Mainsheet tech notes.  Seldom do "brand new problems" arise!!!

It would behoove a new owner (of an older C34) to peruse those Tech notes and see what is there.  I seldom give the quarterly issue and year date, because I'm tired of looking up those dates!!  I've left that task to others like the asker and our Liberian - Stu & a few others.

A thought
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: WBev on December 31, 2021, 09:01:43 AM
I just tried to (finally) download the excel as recommended by Stu in this thread, and get a "404 File not found" message. 
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Stu Jackson on December 31, 2021, 09:45:52 AM
Quote from: WBev on December 31, 2021, 09:01:43 AM
I just tried to (finally) download the excel as recommended by Stu in this thread, and get a "404 File not found" message.

Have you tried replies 4 & 5 in that link, the "Backdoor Approach?"

If that doesn't work, I'll see if I can upload it here.  Sorry, the forum won't take xls files.

PS - I see what you mean, give me some time to look around.

PPS - I tried a few different ways, none worked.  Please give me some more time, thx.
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Stu Jackson on January 02, 2022, 02:17:50 PM
I wrote to Dave Sanner, our excellent and under-appreciated webmaster, who keeps this forum and website up very well & secure.

Try it now, seems to work for me.
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: WBev on January 08, 2022, 09:46:04 AM
Stu: Thank you.  I now can, but my firewall is in the way, saying the file has malware attached.  I will do this on a "sandboxed" machine.
Bill
Title: Re: Exhaust hose, riser, elbow: should I replace at same time??
Post by: Stu Jackson on January 08, 2022, 10:34:40 AM
Quote from: WBev on January 08, 2022, 09:46:04 AM
Stu: Thank you.  I now can, but my firewall is in the way, saying the file has malware attached.  I will do this on a "sandboxed" machine.
Bill

Bill, please write to Dave Sanner (sanner att big dott  net) and ask him to look into this.  I did not have this problem.