When to Replace Exhaust Hose - 352?

[Murray16764]

I was wondering when the engine exhaust hose should be replaced. I have seen what happens when the hose fails and I want to avoid that. I have a Ben 352 (1998) with about 900 engine hours. It's a fresh water boat, if that makes any difference. The 2" hose is original equipment and appears to be in good condition. No issues so far. Thanks.

Murray

 

[JohnShannon]

Oh Man I hadn't even considered replacing that! What does happen? CO and everybody in the quarter berth dies? Oily mess? I have 2k+ hours on a 1985 engine and I guess it is still OK the motor was gone over at the yard a year ago and I trust they would have checked. So you might have a ways to go.

 

[Don S/V ILLusion]

Can't think of a good answer so:

If you are worried about it, the $10 or whatever it cost seems like a bargain.

If you are looking for a more (smart-ass) precise answer, how about 'right before it fails'.

 

[Peggie Hall HeadMistress]

Fwiw, the average working life of ANY hose--fuel, water, sanitation, engine, exhaust--is about 10 years. As hose ages, rubber and plastics (nylon, flex PVC) dry out and begin to harden...when they've dried out enough, hoses begin to crack, blister and split. This is what causes most hose failures to occur on thru-hulls--failures that can result in sinking if the seacock is left open. And yes, exhaust hoses can leak CO.
So if any of your hoses are at least 10 years old, they should be inspected regularly for signs that they're starting to fail...and if you see even the slightest indication, it's time to replace that hose...better yet, all the hoses in that system. If in any doubt, or any hoses are considerably older than 10 years, it's better to err on the side of caution than wish you had.

 

[kloudie1]

Look for the first signs of "checking" which presents as small cracks in the outside or inside surfaces. "usually" these hoses are reinforced with a steel coil so when the inside starts failing, the coil will rust and since rust is 8-10 times more volume than the steel, you'll see bumps in the hose where the cover will start cracking.. My hose is about 30 years old and still looks fine on the outside and the foot or so that I can easily see of the inside.. Mine is in brackish/salt water but it gets flushed/rinsed because my slip is a mile or so up a fresh water bayou.

 

[Johnb]

The exhaust hose in my HC 37 was replaced by the previous owner in 1998 because it was leaking, so at that point it was 15 years old and the engine had about a 1000 hours on it. It is on my list of things to do this year as the replacement is about the same age.
I would expect that the area closest to the engine would fail first because it is subject to max vibration and temperature there.
If it fails you don't just get exhaust gases but raw water as well hosing out. When a piece fell out of our mixing elbow it set off the fire and CO detectors almost simultaneously and caused a big mess.
On the positive side, once it is done you have about 15 years and/or 1000 engine hours before you need to do it again.
Seems that hose is about $15 per foot.

 

[JohnShannon]

What excellent answers thank you now I know what to look for.

 

[Benny17441]

I replaced one recently on a friend's boat and it was way more difficult to find the replacement hose than it was to install it. The hose we needed had different sizes at each end. If you are uncertain about the age and condition of your hose go ahead and get the measurements for it and go online and order a replacement and get new clamps to fit it (2) per side and store in a dry place. Having a replacement handy I would not worry about it until the current one failed. The one that we replaced must have been 12-15 yrs old and it still looked good but it developed a crack in one of the creases. My friend realized the problem when the area under the engine got full of water. In case of emergency go ahead and wrap the hose with duct tape until you can get somewhere and allow the engine to cool down so you can replace it. It is not a failure that would likely leave you stranded.

 

[Peggie Hall HeadMistress]

It is not a failure that would likely leave you stranded.

No...but if it's an exhaust hose, it can leak CO. and duct tape is a very temporary band-aid. So put off replacement ONLY until you get to a place where you can replace it.

 

[Stu Jackson]

• Exhaust Hose Replacement with Pictures EXCELLENT 4 page discussion with Flix by Stu http://c34.org/bbs/index.php/topic,6760.0.html

It's long, pictures are on the later pages. But one of the pictures shows the effect of long term exhaust gas leaks through the hose even without water coming through!

1986 boat, see the dates when it was done in the link.

It's like reefing, if you think you should....

 

[Murray16764]

Thanks everyone for your replay. I am going to have a very close look at it, especially at the engine end. It sounds like it is fairly straight forward job if you are a contortionist, although my boat is very generous in these areas. I might delay this job a year or two if the hose looks sound. Thanks again, Murray.