Phew, that was a close shave!

[Chop!]

On Saturday evening I got Freyja running again after her head skim, we ran her twice more on Sunday then decided to go for a short cruise on Monday, Started her to heat the water for a shower and noticed a smell of diesel, lifted the engine boards and found that about 30 gallons of diesel had siphoned down into the bilge overnight!

We had just fitted a new MLS centrifugal filter to remove diesel bug and water and I had forgotten i had not tightened the drain cock, it had vibrated out, allowing the diesel to siphon out, luckily in working in the bilge I had broken a bilge pump wire or I would have been very unpopular on our lake.

So instead of going for a cruise I spent two long days pumping it out, straining it back in and de-greasing, jet-washing, pumping out and cleaning our bilge.

It does mean I'm closer to being able to paint the rest of the bilge with light grey garage floor paint ;o)

Edited April 24, 2014 by Chop!

[Captain Fizz]

Not a totally wasted effort then.

[ditchcrawler]

Well you should find out how well the filter works if you pumped it back into the tank.

[AndrewIC]

How effective is this likely to be at low flow rates? Even the smallest is rated at 1.9 litres/min, most canal engines will do less than that an hour or does flow rate not affect the centrifuge working?

[nicknorman]

How effective is this likely to be at low flow rates? Even the smallest is rated at 1.9 litres/min, most canal engines will do less than that an hour or does flow rate not affect the centrifuge working?

I think firstly it is just a glorified agglomerator, secondly on modern jap engines including ours, there is a high flow of fuel through the injector pumps and back to the tank, probably corresponding to more than the max possible fuel demand. So even though the engine might be taking 1lph at tickover, the flow through the filter would be a lot more. Obviously on older engines it will be different.

[Chop!]

I will let you know how it performs.

[ditchcrawler]

I think firstly it is just a glorified agglomerator, secondly on modern jap engines including ours, there is a high flow of fuel through the injector pumps and back to the tank, probably corresponding to more than the max possible fuel demand. So even though the engine might be taking 1lph at tickover, the flow through the filter would be a lot more. Obviously on older engines it will be different.

Even my BD3 it is a lot higher than the engine uses, I use the excess to keep the day tank for the cooker topped up.

[AndrewIC]

Interesting, I had always assumed that the amount going back via the leak off pipe would be very small.

[nicknorman]

Interesting, I had always assumed that the amount going back via the leak off pipe would be very small.

Via the leak off pipe on the injectors - yes. But engines such as my Beta have a good flow through the injector pump and back to the tank. This is how they can be "self-bleeding": Lots of air in the system following a filter change? No probs, just operate the manual pump and lots of fuel is pumped through the whole system and back to the tank, taking all the air with it. Or in our case, just turn on the "ignition" and the electric lift pump does likewise.

 

Older engines tend not to have this return pipe from the injector pump and so need to have a screw loosened in order to expel air.

Edited April 25, 2014 by nicknorman

[ditchcrawler]

Mine is via a bleed on the top of the filters as well

[AndrewIC]

And on inspection I find I have such a pipe - I'd never noticed. Bleeding instructions on my beta are to manually pump until the filter is full, tighten the filter bleed, then motor the engine until it starts, which is usually about 20-30 seconds.