Diesel flashpoint?

[Blue Seas]

To clear my conscience, I must repeat parts of my post 4. above.
There are only a few parts in your engine room that have the capability to ignite diesel - and the main enemy by far is the stretch of your exhaust (including the turbo!) that lies between the exhaust manifold and the point of exhaust cooling water injection.
IF that part of the exhaust is lagged (rather than cooled by SW) - and IF that lagging is soaked in diesel - Then it will ignite for sure as the amount of diesel retained in the lagging reduces and hence there is a corresponding rise in temperature.
It took all of the units of two major UK fire brigades three days to put out a fire from that exact cause - and then it re-ignited anyway.
CHECK for no diesel soaked lagging
CHECK for for no diesel soaked rags or other combustible materials.
CHECK that you have removed all above materials from the internal boat space ready to either go ashore or bin overboard pronto.
I have a vision of an opportunity of a mate mine with slippers on his hands trying to hold on to a melting (metal) ladder to escape the fire I described above which was caused by dripping diesel on to exhaust lagging.
CHECK the turbo area for the source of mist.
I'll be quiet now.

 

[john_morris_uk]

To clear my conscience, I must repeat parts of my post 4. above.
There are only a few parts in your engine room that have the capability to ignite diesel - and the main enemy by far is the stretch of your exhaust (including the turbo!) that lies between the exhaust manifold and the point of exhaust cooling water injection.
IF that part of the exhaust is lagged (rather than cooled by SW) - and IF that lagging is soaked in diesel - Then it will ignite for sure as the amount of diesel retained in the lagging reduces and hence there is a corresponding rise in temperature.
It took all of the units of two major UK fire brigades three days to put out a fire from that exact cause - and then it re-ignited anyway.
CHECK for no diesel soaked lagging
CHECK for for no diesel soaked rags or other combustible materials.
CHECK that you have removed all above materials from the internal boat space ready to either go ashore or bin overboard pronto.
I have a vision of an opportunity of a mate mine with slippers on his hands trying to hold on to a melting (metal) ladder to escape the fire I described above which was caused by dripping diesel on to exhaust lagging.
CHECK the turbo area for the source of mist.
I'll be quiet now.

Good points well made. There is a turbo and it is lagged. As far as I can tell there’s no diesel soaked into any of the lagging (it’s on the opposite side of the engine so avoided the soaking the port side got. )

The white haze that stank of diesel has now stopped appearing whenever we start the engine.

 

[Keith 66]

In 1984 i was part of the crew working on the fitting out of a 86ft steel yacht at Tilbury docks. The whole boat was under a scaffolding tent which was sheeted up to allow painting to continue. The painting crew had two huge diesel fired space heaters going one day & for some reason one had a flame out. The flame failure device didnt cut the fuel & the fuel pump continued to pump diesel onto the red hot burner.
The whole boat shed was rapidly filled with thick white smoke to the point you could barely see your hand in front of your face. There was a rapid evacuation of the boat, both heaters had already been turned off.
Looking back the risk of a very large fuel air explosion was very real.

 

[Rappey]

The "haze" was probably the diesel evaporating off the engine when up to running temperature? The more you run it the less haze until all diesel on the engine is gone.

 

[Momac]

Disposable nappies are a good resource,

Or Puppy training pads , which I haven't tried but I have seen a marina neighbour use them and they absorb oil well
For responsible disposal obviously.

 

[Buck Turgidson]

There is most definitely an explosive risk if you have a haze or mist of diesel. It is not the same as liquid diesel.
read the opening of this!
or this

All new commercial aircraft have to have systems to prevent a tank explosion. AvTur is essentially diesel without the lubricants.

 

[Thistle]

I’m wondering if we’ve got any experts on the forums who could give some guidance? I’m currently on a boat where we had a major diesel leak in the engine bay. The secondary filter and water separator on the block of a large Volvo diesel engine had a fault with the O-ring and sprayed 200 or 300 litres of diesel everywhere. We’ve mopped up everything that we can see, but when we now run the engine, there’s a haze of what I assume to be diesel in the engine bay. How dangerous is this? Is it flammable? I’m assuming it’s not explosive. Any suggestions or ideas or guidance as to what we might do? Obviously we will carry on cleaning and the problem does seem to be getting a little better, but is it dangerous?

Coming a bit late to this but I would be VERY wary of a diesel haze. We're talking about the fuel being divided up into tiny particles with a corresponding increase in surface area. In other circumstances, eg in the cylinders of an engine, the fuel is injected as a fine spray on order to help it to burn more readily. An analogy might also be drawn with flour which, while normally rather inert, can be explosive when mixed with air and subjected to a minor source of ignition. Diesel is also harmful if inhaled.

 

[LittleSister]

Others have suggested various products for cleaning up diesel, but in the event that these are difficult to obtain where you are, or too expensive for the overall job, I've read previously on these forums that a strong solution of washing powder (ideally bio?) is quite good for tackling the diesel, and countering the smell.

Good luck with the challenge.

 

[john_morris_uk]

Others have suggested various products for cleaning up diesel, but in the event that these are difficult to obtain where you are, or too expensive for the overall job, I've read previously on these forums that a strong solution of washing powder (ideally bio?) is quite good for tackling the diesel, and countering the smell.

Good luck with the challenge.

Thank you. The owner and his friend plus daughter & her boyfriend have made good progress using Starbright Bilge cleaner. He doesn’t seem to be too worried about the cost of the cleaner. I wanted to get Bilgex, but it wasn’t available in Rol Nautique chandlers in Gran Canaria.

 

[Stemar]

I used bioclean to get rid of a stench of MAB caused by a diesel leak. It contains microbes that eat oil and similar organics. Just pour some in the bilges and let it slop around for a few days. Probably not easily available where you are, but pet shops may well have something similar.

 

[Bandit]

On a D3 the last fuel filter before the engine is under quite a bit of pressure it is after the lift pump so 50 to 60 psi . After the fuel pump it is ultra high psi. The hot spot is the turbo to the water cooled section of the exhaust and any diesel soaked lagging or rags.

 

[Sybarite]

Disposable nappies are a good resource,

That's what I use if there is any dirty water in the bilge (after mopping up as much as I can.)

I use the largest size for toddlers.

When tempted to fight fire with fire, remember that the Fire Department usually uses water.