Bugs not bunny or funny

billyfish

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Well. Just had my first experience of diesel bug ? bunged up pipe and stopped the engine off Bolt head. So luckily diverted to Salcombe. No mishaps. Changed filters and had the inspection cap off the tank and got out what I could which I think was most of it . Looked like it was clinging to the bottom of the tank and got churned up in a big sea...will it come back ? is there more hiding behind the baffles? Got some " fuel set" does it go off ? Any other ideas?
 
pop some marine 16 in there to stop it growing, and add to every refuel. Keep an eye on the filters and you'll be fine but may have to change a few. Make sure there isn't any water in the tank too.
 
Can you drain from the bottom of your fuel tank? If so, after the fuel has settled, take out any water and crud you can. Our tank has a sump with tap for this very purpose. Marine 16 as others have said, and change the filters. We had a dose about 5 years ago, and its not come back. We didn't empty the tank, replace the fuel or have the tank steam cleaned.
 
Marine 16 did a great spot on Sailing Cadoha recently where they explained this stuff alongside their fuel cleaning device designed to remove water. In the video he explained that every diesel powered yacht already has a very effective fuel polishing system installed (the engine's fuel system and return) so cleaning the fuel will happen automatically once you've killed the bug with chemicals. As such, removing water and dirt from the tank is all you really need to do, and for that you can either use a pump or a tap right at the bottom of the tank.
 
As a person who has had Bug and Engine stopped ... sailed on others who have had bug and engine stopped. Yes sounds crazy as a Fuel Blender - but like car mechanics - you become lazy about your own.

OK ... my recc'd path now. (No G'[tee's - but it worked for me and plenty of others I have helped with this - to not have trouble again).

Get a pump or Pela and suck out the bottom of the tank as best you can ... no need to empty tank. You won't get it all out regardless of what you do.

Have new fuel Filters - do not install yet. Now a trick that Volvo Truck service does over here when they have a Truck with problem ... fit filter and then once filter bowl is sealed - get some Startron or Marine 16 or FuelSet ... as long as it is Enzyme based. Squirt a decent measure into the filter via fuel line. Reconnect fuel line.
Pour in a decent measure to the tank ... I suggest about 3x quoted dose. Put in more clean diesel.
Now bleed system ...

The Enzyme in the filter will basically go through the engine system and followed up by diesel.

Start engine and you will probably have to keep restarting or have throttle open high to keep her running .. that's the Enzyme fluid as its not a real fuel ... it may smoke a bit as well !!

Soon the engine will clear and start to run smooth.

Keep a bottle of your preferred Enzyme and add a dose each time you fill up. After a seasons use - your tank should be pretty clean - without all the kerfuffle and trouble ...

The trick is to be able to break up the gunge and burn it in engine ...

My last Bug event on my boat was approx 10yrs ago ... and that was actually my own fault. I had about 500ltrs of samples from my lab and I mixed them ... Heating Oil ... ULSD ... Russian Exprt GasOil ... N0.4 ... FOD40 ... etc all sorts of grades that on own would be fine in an older diesel like mine. But some of the samples were bad and labels had fallen of ! Even with filtering, 2 micron - the condition ended up stopping my Perkins ! I'm not afraid to admit my error !

Using the above 'method' - my engine has not had bug problem again. In fact even though I have run out of Emzyme and only last used it summer last year - the 50odd ltrs that sat in my 70ltr tank since then has been fine on relaunch recently. I have had significant hours on engine since relaunch ... all fine.

OK - last point : Some talk about Bugs and having them 'live' in their tanks ... fact is when alive ... they actually are a very small problem. The problem comes when they die ... THIS is the crud you find in tank and gets sucked into and clogs filters when UNBROKEN.
Second Bugs are NOT only in the Fuel - Water interface .... there are others - SRB - Sulphur Reducing Bacteria - which lives in the fuel itself. SRB luckily is in decline as Sulphur levels are reduced in fuel.
 
Thank you guys. I cleaned the tank by hand best I could through inspection hatch...added 50ml fuel set. Ran for 6 hrs today with no misfires ....
 
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