Broken diesel fuel line whilst motoring this afternoon

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AAF

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Was out in Weymouth bay this afternoon in my Broom 39 (VP D4 260HP) and sticking close to the Portland harbour wall and just pootling along as it was certainly lumpy any further out. Suddenly a horrible burning smell with smoke and mist coming up the stairwell into the cockpit from the cabin.

More than slightly worrying....

Took up the cabin floor and diagnosed it was the starboard engine so shut it down. Further inspection revealed litres of diesel in the bilge under the engine.

Started to trace the fuel lines and the engine areas smeared with diesel and concluded that the problem was under the engine cover so removed that. Nothing obvious but when the engine was (briefly) turned over there was a leak (i.e. spurting atomised diesel) from what I think is the diesel return line. There is a chamber on top of the block that has an inlet pipe, 4 pipes leading to each of the cylinders and one heading aft and then down through various engine bits so I am assuming it is the return line. There is also a pipe supporting clamp missing from the run of this pipe so a possible cause of failure is vibration. (We actually found a part of a clamp in the bilges during the survey in July last year before I bought the vessel but could not identify from where it came. Now I know!)

I am not sure of the flash point of diesel but looking back was I lucky not to catch fire?

Back to the main question. Do the forum engine experts consider that the pipe failure is very likely this clamp bracket absence and replacement of this failing part is all that is required? Or should I test and/or replace all the fuel pipework as once one of them fails all the others are suspect? What about the port engine that has done a similar 435 engine hours - is that also suspect? Your thoughts welcome.

Also any recommendations as to how to clear up the diesel in the bilge? I am sure I am not the first with this opportunity.

I am supposed to be taking my twin daughters for a birthday spin around the bay on Saturday, but that looks unlikely unless I can get the replacement part tomorrow. Any recommendations as to where to go to source the part?

To conclude the story we made it back to my Weymouth marina berth on port engine alone and without hitting anything. I had the marina staff standing by to nudge if necessary as it was very gusty in the harbour. Thank goodness for the speed of "extremely dead slow" and the bow thruster. It would not have been impact free this afternoon were it not for that piece of boat equipment.
 
When similar happened to me on an injector pipe Poole diesel sorted it the very next day. I suspect this will be a VP or Bosch specific part as I assume the D4 is a common rail (devil's) engine. Worth a try though.
 
I remember a few years back delivering a new Broom 39 from SIBS to Lymington, had 8 hours on engines, got as far as Fawley and the alarm went off on one engine, I lifted floor and saw diesel under engine, it was a bit lumpy so shut down and carried on with other engine, was met in marina by Volvo dealer who lifted floor and said that's third one like that he's seen, it turns out to be a clamp missing off return line which causes it to fracture, was easily fixed but mess it made was another story, I'm not sure all the details as it would have been about 10 years ago and not heard of problem since.
 
Thanks for all replies. There has been progress.

I mopped up this afternoon, there was 4.5 litres of diesel liquid in the bilge. I have applied fairy liquid and additional fresh water and hope for a good agitation next time we go out. (Strange thought really).

Mechanical Services (Weymouth VP agent) have inspected and confirmed the fractured pipe. They say it is the inlet not the outlet fuel pipe and the cause is the missing pipe clamp. They say it will be repaired on Friday subject to VP central stock delivering the part. I took off the port engine cover and that clamp is still firmly in place. (Phew!)

So onwards with the boating learning curve.

Regarding the fire hazard, Google says that diesel flashpoint is between 52 & 96 degrees C and the exhaust and other engine parts must be above 52C. So the reason we did not burn must be something to do with the diesel air mixture in the cabin?

And a benign God...

(Still extremely thankful we didn't!!!)
 
Same thing happened on tcm's D2 mid channel. The first we knew about it was when the bilge alarm went off.... there was so much diesel in the bilge.
Limped into Roscoff and managed to get a local guy to make a new one.
 
Was out in Weymouth bay this afternoon in my Broom 39 (VP D4 260HP) and sticking close to the Portland harbour wall and just pootling along as it was certainly lumpy any further out. Suddenly a horrible burning smell with smoke and mist coming up the stairwell into the cockpit from the cabin.

More than slightly worrying....

Took up the cabin floor and diagnosed it was the starboard engine so shut it down. Further inspection revealed litres of diesel in the bilge under the engine.

Started to trace the fuel lines and the engine areas smeared with diesel and concluded that the problem was under the engine cover so removed that. Nothing obvious but when the engine was (briefly) turned over there was a leak (i.e. spurting atomised diesel) from what I think is the diesel return line. There is a chamber on top of the block that has an inlet pipe, 4 pipes leading to each of the cylinders and one heading aft and then down through various engine bits so I am assuming it is the return line. There is also a pipe supporting clamp missing from the run of this pipe so a possible cause of failure is vibration. (We actually found a part of a clamp in the bilges during the survey in July last year before I bought the vessel but could not identify from where it came. Now I know!)

I am not sure of the flash point of diesel but looking back was I lucky not to catch fire?

Back to the main question. Do the forum engine experts consider that the pipe failure is very likely this clamp bracket absence and replacement of this failing part is all that is required? Or should I test and/or replace all the fuel pipework as once one of them fails all the others are suspect? What about the port engine that has done a similar 435 engine hours - is that also suspect? Your thoughts welcome.

Also any recommendations as to how to clear up the diesel in the bilge? I am sure I am not the first with this opportunity.

I am supposed to be taking my twin daughters for a birthday spin around the bay on Saturday, but that looks unlikely unless I can get the replacement part tomorrow. Any recommendations as to where to go to source the part?

To conclude the story we made it back to my Weymouth marina berth on port engine alone and without hitting anything. I had the marina staff standing by to nudge if necessary as it was very gusty in the harbour. Thank goodness for the speed of "extremely dead slow" and the bow thruster. It would not have been impact free this afternoon were it not for that piece of boat equipment.

Without a picture it is very difficult to visualise the failed components particularly as I suffer from VP blindness, however from your description it does seem to describe fuel return, one pipe from the rail via pressure reducing valve and one from each injector. Bosch only supply pump, rail, injectors and some sensors, fuel lines etc will be VP responsibility, perhaps the Volvo experts here have seen this bracket failure. checking other support brackets would be smart, leave the other pipes alone.

Sounded pretty dramatic a bit frightening but return pressure not huge and minimal risk of fire.

Trevor, CP3 fuel cooled pump with common rail injectors, utter, utter simplicity and reliability, how can anybody describe that as a Devil's engine??
 
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Pictures

P1050664_zps92ds3rvx.jpg


The pipe that fractured starts just above the third screw hole for the cover and runs horizontal left to right in the picture before disappearing into the bowels of the engine

P1050665_zpsvworfrgf.jpg


The fracture occurred in the bend where you can see some paint has flaked away. This is on the curve and is under the pipe leading to the 4th cylinder

P1050666_zps5jfyzyjr.jpg


And here in the top right hand quadrant is the screw hole that should have held the pipe in a clamp so that it did not fracture.

I am told by the VP agent that this is the feed pipe not the return pipe.

(I did all this with arrows in a word file, then printed to pdf and then found I could not upload pdf files to photobucket. Anyone know how to get pdf into the YBW system?)
 
AAF,

Pictures make all the difference, My apologies for treating this so lightly, failure of the high pressure line is a class 1 failure.

Obviously loss of this support brace is a critical item. I have no clue how VP failure reporting system works but I would demand to know possibly under freedom of information if there has even been a service topic issued on this.

We are dealing with 1,800 bar here, never did my 14.6 times table but just think about it around 26,000 psi is something to be taken seriously.

One for VP guys do they lift cover and check security of fuel line brace when servicing??
 
Couple of points:

Flash point is not ignition temperature.
https://en.wikipedia.org/wiki/Flash_point worth a read.
The flash point of a volatile material is the lowest temperature at which it can vaporize to form an ignitable mixture in air.
Diesel autoignition temperature is 256 C

Also where there is evidence of diesel being sprayed extreme caution should be taken in case the leak is from a high pressure line such as an injector line. Always wear goggles and keep well away since a diesel injection is a big problem: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2532970/
In injection injuries, prompt diagnosis and immediate aggressive surgical intervention are necessary to save the patients' digit/limb. Patients should be informed about the severity of their injury, its potential complications and the multiple surgical procedures that may be required for a satisfactory functional result.
 
I am surprised the engine still ran as this is the high pressure supply from the pump to the rail and any leak should result in the pump going to max output to maintain pressure and probably trigger a fault code, it must have been just inside the limits. I have never seen this fault on a D4/6 yet and we don't remove the engine cover during normal servicing so the clamp isn't checked. could this be the next recall on these engines?
 
Obviously loss of this support brace is a critical item. I have no clue how VP failure reporting system works but I would demand to know possibly under freedom of information if there has even been a service topic issued on this.

The FOI act only applies to (some) public bodies, I'm intrigued as to how you anticipate he could use it here?
 
The FOI act only applies to (some) public bodies, I'm intrigued as to how you anticipate he could use it here?

Thank you noted, too used to dealing with engine issues outside these shores. Having dealt with Cat, Cummins, and Detroit Diesel on a regular basis, they are an open book on any product issues, my experience with MAN and in a far more limited way Volvo leads me to believe that one needs to be far more coercive.

However D4/6 has now been in production for a good few years now and from Spannerman's reassuring response seems like an unfortunate one off occurrence.

Time to fix the issue and move on.
 
Thanks to everyone for their support and comments

Issue fixed this afternoon. New pipe installed. Engine ran up normally with no delay and no visible leaks, though I will keep a wary eye for a few weeks.

The fractured pipe is confirmed as the supply pipe not the return pipe so the hole must have been minimal in size to allow the engine still to run; Spannerman's point. There was noting visible when the removed broken part was inspected this afternoon and the pipe itself did not flop around from the breakage, so it must be a very microscopic hole.

Diesel mist and hot burning smell was in great abundance coming from the cabin up to the cockpit at the moment of failure. I cannot comment on Latestarter1's number of 26000 psi as I am no engineer but there was certainly a lot of diesel mist in a very short time. And 4.5 litres of diesel in the bilges when I cleaned up after probably only running the engine post-event for less than a minute before shutting down after the fault source was diagnosed.

After more Google research I take the point about flashpoint and auto-ignition temperature so probably the risk of burning was not high. On the other hand we were not boiling the kettle on the gas hob at the time and if we were I think it could have been a far worse outcome. The diesel mist was pretty thick and yet disappeared very quickly once the engine was switched off. It would appear that it shot out of the fracture onto the engine block and then got bounced back and force-diminished by the engine cover itself. There was still a lot of it floating in the cabin air and no masks or goggles to hand, Dougal Tolan's point. I consider the life jacket as normally adequate, as I suspect most of us do, and I don't think I will add goggles to the list based on this experience.

Superheat6K, Tico and Aquapower seem to have experienced a similar problem. But I don't think this could ever be a recall issue, at most a recommendation to check the clamp during a service. There are only 9 screws holding the cover down over the top of the engine to reveal the clamp's absence or presence so its not a big deal to make the check. I inspected the port engine on Wednesday for which the clamp was firmly in place.

I certainly do not in any way blame the surveyor last year who noticed the half of the clamp in the bilge but could not identify from where it came. Perhaps the lesson is that when a portion of something VP green but of unknown origin is found, remove all covers for a mark1 eyeball inspection "just in case"!

I now await the invoice. As with all accidents so long as the only damage is metal and the wallet, actually that is a good outcome.


Anyway, we shall have a pootle around Weymouth bay tomorrow and agitate the fresh water/fairy liquid mixture currently in the bilge. The family will enjoy themselves and I shall be worrying about the next thing to go wrong.
 
Thanks to everyone for their support and comments

Issue fixed this afternoon. New pipe installed. Engine ran up normally with no delay and no visible leaks, though I will keep a wary eye for a few weeks.

The fractured pipe is confirmed as the supply pipe not the return pipe so the hole must have been minimal in size to allow the engine still to run; Spannerman's point. There was noting visible when the removed broken part was inspected this afternoon and the pipe itself did not flop around from the breakage, so it must be a very microscopic hole.

Diesel mist and hot burning smell was in great abundance coming from the cabin up to the cockpit at the moment of failure. I cannot comment on Latestarter1's number of 26000 psi as I am no engineer but there was certainly a lot of diesel mist in a very short time. And 4.5 litres of diesel in the bilges when I cleaned up after probably only running the engine post-event for less than a minute before shutting down after the fault source was diagnosed.

After more Google research I take the point about flashpoint and auto-ignition temperature so probably the risk of burning was not high. On the other hand we were not boiling the kettle on the gas hob at the time and if we were I think it could have been a far worse outcome. The diesel mist was pretty thick and yet disappeared very quickly once the engine was switched off. It would appear that it shot out of the fracture onto the engine block and then got bounced back and force-diminished by the engine cover itself. There was still a lot of it floating in the cabin air and no masks or goggles to hand, Dougal Tolan's point. I consider the life jacket as normally adequate, as I suspect most of us do, and I don't think I will add goggles to the list based on this experience.

Superheat6K, Tico and Aquapower seem to have experienced a similar problem. But I don't think this could ever be a recall issue, at most a recommendation to check the clamp during a service. There are only 9 screws holding the cover down over the top of the engine to reveal the clamp's absence or presence so its not a big deal to make the check. I inspected the port engine on Wednesday for which the clamp was firmly in place.

I certainly do not in any way blame the surveyor last year who noticed the half of the clamp in the bilge but could not identify from where it came. Perhaps the lesson is that when a portion of something VP green but of unknown origin is found, remove all covers for a mark1 eyeball inspection "just in case"!

I now await the invoice. As with all accidents so long as the only damage is metal and the wallet, actually that is a good outcome.


Anyway, we shall have a pootle around Weymouth bay tomorrow and agitate the fresh water/fairy liquid mixture currently in the bilge. The family will enjoy themselves and I shall be worrying about the next thing to go wrong.
I have found that Bilgex works really good, it has a deoderant in it as well.
S
 
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