My first "catastrophic failure" (exhaust elbow)

[SV Bacchus]

Originally Posted by lordlefrog

Yeah, unlimited tow is only around $170 a year. Basically, you paid almost 10 years in one incident. If you own a 30+ years old boat, I think it is a no brainer.

I was going to put the math out there but you beat me to it.

I wouldn't be without the Unlimited Plan!

[Captsteve53]

Since we are on my favorite subject with marine failures would just like to comment on these new stainless steel risers being raised,

1) Try and find a stainless riser made from minimum 316 grade even better as 316 L
2) 304 grade stainless does not do well in heated sea water conditions (such as risers/mixers) it can corrode nearly as much as a standard cast iron/steel riser mixer's and as they are normally built very lightly so the time to the failure point is often the same.
3) If going the Stainless steel route and having custom made or other try to find 321 grade stainless steel (harder to find but not impossible), 321 is made for hot sea water/chemical type application's,

The welding of the riser at the manufacture stage and the welding rods/wires used even if TIG/MIG/or electrode will dictate the longevity of the riser in most cases as during welding Stainless Steel under goes chemical changes and if the correct rod is not used then these changes are compounded,I have been called on numerous times to investigate complaints regarding failed Stainless risers/mixers/manifolds where the company manufacturing had no real idea of the properties/correct methods required for Stainless Steel welding or their applications,

Bottom line is to not expect your new SS riser is with out fault and still needs to checked at the same intervals as per normal,

Cheers Steve, IIMS surveyor(Lloyd's Maritime accredited)

[1boat2many]

Originally Posted by Jd1

Well unless the cooling water is injected at the side of the break that was still attached to the engine and unless the engine was tilted in such a way that the water flowed backwards towards the engine (well in that case it would never have run period) then I still can't see how this would destroy an engine. Further, if we assume that water got into the exhaust manifold and was sitting on the other side of the exhaust valves, I can only see how ONE connecting rod was bent if water got into the cylinder through an open exhaust valve but no way (that I can see) would all three rods be bent because turning over the engine would blow the water away from the valve.

I should also add my doubt that the starter could turn over a hydrolocked engine ... well maybe if it had a good run at it maybe one connecting rod but three ?????

On hindsight, I guess if there was only a tiny bit of water in the cylinder, enough to allow almost a full stroke but not quite, then the starter might have enough umph to pull it through ?

When the engine was cool enough to inspect, I saw water in the lower section of the elbow (connected to exhaust manifold), nearly full to the brim. The raw water injection point comes into in the mixing elbow above the tailpipe connecting the two, on the engine side. After having made this observation, it didn't click for me that I should leave it alone. I just saw this as an exhaust problem, and was a bit fixed on the idea that I needed to know if the engine still turned over.

[Dockhead]

Originally Posted by JPA Cate

Hi, 1boat2many,

That's a sad story, with a happy ending.

Here's something to consider doing or having done. When the engine rebuild is being done, they will order you a new "consumable" $500 exhaust elbow. Have a machine shop make you up one out of s/s. Use the s/s one, keep the other for a spare.

Ann

+1 on this.

Moody's yard threw away the standard exhaust elbow on my 4JH3 HTE when my boat was built, and substituted a massive 316 stainless steel unit they welded up themselves. It lasted 15 years before it started to leak a bit through some pinholes in the welds.

I had a new one made up for only about $500 at the excellent machine shop in Cowes. Must weigh 10 pounds -- massive thing out of heavy tubing, beautifully welded. Forget the standard part.


To the OP: A bad exhaust elbow should not have killed your engine. There should be a high loop between your exhaust manifold and where the water is injected, to protect your engine from this. If it's not designed like that, then I suggest you have it redesigned and reconfigured. Feeling your pain It's bad enough that a bad exhaust elbow can sink you. For that, make sure you have a bilge alarm in your engine compartment, if it has a separate bilge, and in the main bilge, otherwise.

[JOHNMARDALL]

You handled that cascade of problems well. Water did not get into the cylinders when the engine was running at any speed, that could only happen through the intake valves, which are not connected to the exhaust and mixing elbow side of the system. Exhaust side cylinder flooding can only occur on shutdown and thereafter. In your case, the damage almost certainly occurred when you tried to re-start, with the impeller pump pushing water into the damaged system, and with bad luck, into the exhaust manifold and from there through any open valves and into the cylinders . That's why this problem is so insidious - it happens after shutdown. One device that can help is an exhaust gas temperature alarm, which will sense any significant increase in temperature after the mixing elbow, but only while the engine is running - it may have reacted in your situation before things went completely over the edge.
Again, well done on keeping a cool head in a difficult situation - all's well that ends well.

John Mardall
Vetus Maxwell Group

[ArmyDaveNY]

Originally Posted by 1boat2many

Regarding the cost for the tow - covered by my regular insurance policy to 5K, but now I wonder if going forward I should spring for the BoatUS unlimited coverage since it's what they are there for.

BoatUS and SeaTow are both pretty good. BoatUS actually has two towing packages. The first one, Unlimited Saltwater Towing, is around $149 (including the $24 BoatUS membership) and is for emergency towing within a certain range. If you have a breakdown on the water as described they will tow you up to a certain number of miles back to a dock, including yours if it is within range.

The second type, Unlimited Gold Towing, is basically a dock to dock towing including emergency towing when on the water. It is around $169 and in addition to the emergency towing, they will pick you up at a dock and tow you to another facility. This is very useful if the marina or mooring you are at doesn't have the facilities you need. It kicks in after 30 days of signing up and includes emergency and non emergency towing.

Not everyone needs the Unlimited Gold but it is a good program for those who need it. Either way, both BoatUS and SeaTow are great programs.

[evbeck]

This is all too familiar - having suffered a fracture in the elbow of our Westerbeke 82B last Fall and getting towed for a few miles in the ICW. We then got caught in "Matthew" and have just finished a challenging eight-month repair project from the Hurricane damage. On the sea trial two weeks ago, nearly all systems checked out and then the flange in to the exhaust elbow split and exhaust was dumped in to the engine room. We need two new flanges to connect pipe to the elbow and on the lower end, to the manifold, and a new manifold due to some corrosion there.

Only problem is that on a 2004 engine, those two parts - the flanges and the manifold - take six weeks to get from Westerbeke. We have the parts on order, but are very disappointed after the long repair project not to be on the water at this point. Seems like the exhaust and cooling systems are a constant risk.

[foufou]

Not certain SS is the best material. My Ss elbow is bleeding rust at the welds. Will have to inspect it. There was a recent mention of a bronze exhaust elbow from Yanmar. Good luck

[MV Wanderlust]

Thanks for the open and honest confessional. The end result could have been much worse, considering all of the traffic around you. You're home safe and able to talk about it. That's the important part. Sounds like a reasonable rate for the rebuild. Thanks for the warning. Something to check, for sure.

[Deltasailor]

Originally Posted by lordlefrog

Yeah, unlimited tow is only around $170 a year. Basically, you paid almost 10 years in one incident. If you own a 30+ years old boat, I think it is a no brainer.

So sorry for your problem but thanks for pointing that out I should check my Yanmar elbow ASAP.
One thing though, golfer Henry Cotton said "When in trouble get yourself out the easy way". Don't try to do what the boat can't. Sail to a safe haven then worry about what to do. After a good nights sleep you can figure out the best course of action. Don't try to do what the boat can't.
This get you home service is new to me (in the UK and Greece) It encourages folk to assume a call on a cell phone will fix the situation. Not a good plan, I will always try to sort my self out.

[boeing1]

I might be wrong but I think Yanmar suggest that the mixing elbow should be checked or replaced after so many hours, I have replace several on friends boats

[a64pilot]

Originally Posted by foufou

Not certain SS is the best material. My Ss elbow is bleeding rust at the welds. Will have to inspect it. There was a recent mention of a bronze exhaust elbow from Yanmar. Good luck

SS is not, not a whole lot better than Iron.
Bronze if it can be done is the way to go, some Yanmar elbows are bronze, mine is. I don't know why not all are?
Actually Titanium would be the best, no idea as to cost though, this is a decent article covers mostly power boats though, but principle is the same and does cover different materials to some extent
http://www.yachtsurvey.com/exhaust_risers.htm

[qwert]

Another even more serious consequence of a failing exhaust is the potential leakage of carbon monoxide. Crossing the (English) channel many years ago my father went below after a couple of hours motoring one cold and calm night to find his crew lying on the floor , slightly blue and deeply comatose. She was very lucky to survive and would never step on a boat again. A thorough examination found a very small leak in the exhaust. The smell was so faint, even after an hour or more of running that you could only detect it if you 'knew' it was there.

[1boat2many]

Thanks all for the feedback - I have a little time to do my homework while the engine is being rebuilt - maybe start a new thread with results? Anyhow - much appreciated!

[BobFord]

Excellent post" 1 boat" , my Yanmar's 4JH4HTE , are 5years and 1400 hours.
I neglected to strip and check elbows because they " looked brand new "
Guess what today's job is ? Sorry about your experience.