'THERE IS SMOKE EVERYWHERE!!' not what you want to hear 40mi offshore....

[oscarvan]

Isn't this what the "emergency shutdown" spring loaded air flaps are for?

Only if they are running in the right direction. Then there is suction and the flaps will slap and seal shut cutting off the air supply. If it's running backwards there is exhaust pressure there and it will easily force the flap open.

 

[oscarvan]

Running backwards is not a common occurrence, especially in boats. I've had it happen once on a truck but I've never heard of it happening on a boat. I don't think it happened to Rusty and I don't think you have to worry about. Just my opinion after growing up around these engines for 50 years.

It is rare. But again, some Googelating reveals it is not unheard of.

 

[rustybucket]

Recommended idle speed per the manual is 550. How low did you have that one set?

500 for port (the seized motor)

480 for stbd (the motor that is fine)

 

[rustybucket]

Running backwards is not a common occurrence, especially in boats. I've had it happen once on a truck but I've never heard of it happening on a boat. I don't think it happened to Rusty and I don't think you have to worry about. Just my opinion after growing up around these engines for 50 years.

So, I'm not married to the idea either but it's the only thing I've come across that explains all the symptoms seen (so far).

- smoke filled engine room and cabin with funky smell (while at idle speed, not running)
- seized engine (appears from no oil flow)
- fresh saltwater on exhaust side of turbos
- soot and strong 'smoke smell' inside of air seps (not present on other engine)
- no alarms or pegged gauges while it was happening

What's your opinion on what failure could display all of these side-effects?

 

[SKYCHENEY]

So, I'm not married to the idea either but it's the only thing I've come across that explains all the symptoms seen (so far).

- smoke filled engine room and cabin with funky smell (while at idle speed, not running)
- seized engine (appears from no oil flow)
- fresh saltwater on exhaust side of turbos
- soot and strong 'smoke smell' inside of air seps (not present on other engine)
- no alarms or pegged gauges while it was happening

What's your opinion on what failure could display all of these side-effects?

I would agree that its possible and with lower than recommended idle, its more likely. But low idle could be the culprit by itself. Lower than spec can cause low oil pressure and less coolant flow. Once rebuilt, I'd put them both back at recommended idle speed. I don't think the manual calls out 550 arbitrarily. Its there for a reason.

 

[Retired1]

My hats off to you for your “go gettingness” of tackling the issue in such a quick manner. Having been a yacht broker for so many decades in Miami, I’m used to these problems being solved by “oh, you didn’t hear, someone stole her from my dock last night”. or “you didn’t see it on tv? There were many fire engines at the marina, but they failed to extinguish the fire, and she burned to the waterline, but thanks for the tip about cinching tight plastic tie wraps of dry newspaper behind the electrical panel tightly with all the power turned on as I drove to the drug store at 4am”. God bless you for not going that route. There’s no hurricanes heading your way are there? Lol

 

[rustybucket]

I would agree that its possible and with lower than recommended idle, its more likely. But low idle could be the culprit by itself. Lower than spec can cause low oil pressure and less coolant flow. Once rebuilt, I'd put them both back at recommended idle speed. I don't think the manual calls out 550 arbitrarily. Its there for a reason.

#1 I have plenty of oil pressure at idle.

#2 That engine was off the majority of the morning, only fired up to turn the boat or jog to the next number. At all times it's rpm would have been well above 550, more like 1000-1100rpms.

#3 We are not seeing low oil pressure symptoms, we are seeing NO (zero) oil pressure symptoms.

#4 at no point during the day (or ever) have I received a low oil pressure alarm on either engine.

If this had happened to stbd engine (which is idled at 480 and idles/trolls for long periods of time) I think your theory would have some ground to stand on, but my port engine is rarely idled, plus it has good oil pressure. It wasn't a tired old engine, fairly fresh off rebuild (500 hrs).

 

[rustybucket]

Early on in this project I recognized that organization of parts was going to be a huge factor in the success/failure of the rebuild. I've used ziploc baggies with sharpie labels for the majority of parts. I've used cardboard with X's cut in for holding bolts in particular arrangement. But the heads had a variety of odd shaped parts and here is what I came up with.

Cardboard with parts zip tied to them. Each cylinder gets it's own piece of cardboard and is labeled appropriately so a set of rockers from cylinder 3 goes back onto cylinder 3.

 

[rustybucket]

My hats off to you for your “go gettingness” of tackling the issue in such a quick manner. Having been a yacht broker for so many decades in Miami, I’m used to these problems being solved by “oh, you didn’t hear, someone stole her from my dock last night”. or “you didn’t see it on tv? There were many fire engines at the marina, but they failed to extinguish the fire, and she burned to the waterline, but thanks for the tip about cinching tight plastic tie wraps of dry newspaper behind the electrical panel tightly with all the power turned on as I drove to the drug store at 4am”. God bless you for not going that route. There’s no hurricanes heading your way are there? Lol

lol, that's funny. After a near miss with Fred looks like we are clear for a bit at least. We still have stbd engine so I can go wherever I need to go to move away from a storm.

 

[racclarkson@gmail.com]

Your organizational skills are only exceeded by your initiative.

 

[Play'N Hooky Too]

You must not have any kids around....

Pictures!! Take lots and lots of pictures!

 

[SKYCHENEY]

#1 I have plenty of oil pressure at idle.

#2 That engine was off the majority of the morning, only fired up to turn the boat or jog to the next number. At all times it's rpm would have been well above 550, more like 1000-1100rpms.

#3 We are not seeing low oil pressure symptoms, we are seeing NO (zero) oil pressure symptoms.

#4 at no point during the day (or ever) have I received a low oil pressure alarm on either engine.

If this had happened to stbd engine (which is idled at 480 and idles/trolls for long periods of time) I think your theory would have some ground to stand on, but my port engine is rarely idled, plus it has good oil pressure. It wasn't a tired old engine, fairly fresh off rebuild (500 hrs).

I'm not saying it didn't run backwards. Exhaust throughout the boat suggest that it could have. I guess I'd just be surprised that it ran that way long enough to do damage.

You'll know more once you get the liners out.

 

[cww]

Have you considered the possibility that you may have ingested water on that engine through the scoop intake when you were running on the other engine with that one shut down to troll? If the plate in the water pump gets worn some amount of water can slip past the pump under positive pressure. From your description of a loud clunk and the starter being unable to turn it over, it sounds like that engine was hydrolocked when you went to start it.

The smoke could just be oil or coolant dripping onto a hot exhaust, or any number of unrelated things. I wouldn't automatically assume the two are the same cause, especially when your post says that engine was shut down during the time the smoke developed. I think that scenario is far more likely than the engine somehow accidentally starting backwards.

 

[oscarvan]

it sounds like that engine was hydrolocked when you went to start it

I can see that happening not through the water pump but up the exhaust.....

How "lively" was the water?

 

[dsharp]

I would be more inclined to believe water entered through the exhaust when you consider that the muffler is approximately 1/2 full of water when you shut the engine down. I would much prefer to leave booth engines running even if trolling on one engine.

 

[rustybucket]

I would be more inclined to believe water entered through the exhaust when you consider that the muffler is approximately 1/2 full of water when you shut the engine down. I would much prefer to leave booth engines running even if trolling on one engine.

Actually my mufflers are not really underwater at all under medium or light loads, which we were very light that day, so I doubt the muffler had any water in it other than from the raw water injection showers.

So, you would idle an engine (out of gear) for hours at a time? We very often shut engine(s) down while offshore. It makes up a significant fuel burn difference for us over the course of a multi day trip, plus I feel like it's already not good to idle these engines for extended periods of time, so I shut down to avoid any unnecessary idling.

 

[rustybucket]

Have you considered the possibility that you may have ingested water on that engine through the scoop intake when you were running on the other engine with that one shut down to troll? If the plate in the water pump gets worn some amount of water can slip past the pump under positive pressure. From your description of a loud clunk and the starter being unable to turn it over, it sounds like that engine was hydrolocked when you went to start it.

The way my exhaust/engine is setup even if you forced water through the scoop it would just enter the exhaust at the top of the engine room on the downhill slope of the exhaust and exit the boat through the mufflers. This is not a exhaust lift setup. What you are describing just could not physically happen with the exhaust/engines setup the way they are.

 

[rustybucket]

The smoke could just be oil or coolant dripping onto a hot exhaust, or any number of unrelated things. I wouldn't automatically assume the two are the same cause, especially when your post says that engine was shut down during the time the smoke developed. I think that scenario is far more likely than the engine somehow accidentally starting backwards.

It was not automatically assumed. Everything was closely inspected. No signs of fluid leaking on any hot exhaust surfaces was found.

 

[rustybucket]

I can see that happening not through the water pump but up the exhaust.....

How "lively" was the water?

What do you mean by 'lively'? The water that was on the exhaust side of the turbos was 100% seawater. No coolant, no oil, it had not been through the engine.

There were signs of that water being sucked in through the turbos and blown into the exhaust manifold. By the time it got to the exhaust side of the heads it appears it was just a mist/spray.

There were no puddles of water in any cylinder. The engine was not hydrolocked. The cylinders did show signs of galling, heat and salt mist/spray.

 

[rustybucket]

I guess I'd just be surprised that it ran that way long enough to do damage.

If it were idling, in reverse rotation, without me knowing about it.... How long do you think it would take to seize up a reverse idling engine with no oil or raw water coolant flow?

I have no idea what the answer is, but it would be very interesting to know.