fuel return line?

OK this may be a completely nuts suggestion but what if you placed a nobel gas cap on the fuel
IE
fill the tanks and then inject a small amount of argon into it, this stuff is hevier than air and would block oxygen from the fuel any water that ended up in a layer on top of the fuel would be devoid of oxygen and unlikely to develop aerobic bacterias, anaerobic yes but aerobic no. Might just solve the problem if the bacterias we are talking about that degrade the fuel are of the right class
just a thought
B

 

Not a very practical solution Boston.
The water is at the bottom of the tank, shielded from air by an immense layer of diesel fuel, they'll never notice the argon on top of it all.

I suppose the bacteria are anaerobic, although oxygen does play a role in the process. My info comes from the alt.sci.chem newsgroup where I discussed the phenomenon two years ago and got response from a bacteriologist who seemed to know everything about it.
Unfortunately now that I have direct internet access through a satellite link, I cannot communicate with newsgroups anymore.

I witness the same process in the bilge of my boat.
There is about 1" of water there the pump cannot pull out.
One engine has a leaking seal in the injection pump and leaks some diesel fuel in the bilge. The bacteria build their structures and release gases with a pungent smell.
I used to add water so the pump could do its work, but that solved the problem for a few days only, especially in warm weather.

Then I followed this guy's advice and put a few drops of bleach in the bilge, instantly killing all bacterial life. I do that once every month now.

 

AT 1800 RPM a 6-71 will take 35 gph from the tank, burn what is necessary to operate the load and return the rest.

Since most boats are propped to turn 2100 at full throttle , considerably less fuel is burned at any lower rpm (see any prop load graph).

On every DD fuel system the fuel tanks feed AND return are switched at the same time because of the huge return of hot fuel.

The heat is intense , on one of out 100G tanks , running down to 5 gal (to check accuracy of flow meter and dock pump meter) the tank is too hot to hold a hand on.

For those that haven't used DD this is the setup.

The basic style has 3 rocker arms per cylinder with simple pushrods to operate..

2 rocker arms allow the exhaust to leave on cam selected time.

the 3rd is also cam operated and pushes on the injector , which is the pump to get injection pressure.

The supply of fuel is connected to each injector ( "jumper struts") from a long, internal with the head, fuel manifold.

The govenor simply allows the injector to fill depending on load, by allowing low pressure fuel into the injector.

The skill in any DD is "Running the Rack". Each injector is connected/controlled by the gov by an adjustible conection.

6 cylinders , all 6 injectors must operate at the same time and matched angle of fuel fill.

Changing injector size (size of the fuel squirt) and cam timing is how DD is able to get the same engine to be a 2100rpm fish killer engine , an 1800rpm pump or emergency genset , or even a 1200 long term base gen set.

Takes quite a while!

FF

 

I suggested earlier that the fuel was not internalized. I must have forgotten but Fred seems correct - I thought that the injectors were outside the valve cover. As to quantity, the system is designed to have more fuel than the injectors need and no more, almost as much sent back as burned, so every cycle will incorporate 50% new fuel fuel out of the tank. I do not favor this technique, I do not comprehend any advantage to doing this nor are we now on the cusp of transforming a tired, notoriously filthy, loud, non-PC technology into the first overunity device (it will still draw fuel from the tank). There will be a HP loss.

 

What you need is more of a pousse-café of petroleum products, with something between the water and the fuel. Good luck with that.

http://en.wikipedia.org/wiki/Pousse-café

 

I do not comprehend any advantage to doing this nor are we now on the cusp of transforming a tired, notoriously filthy, loud, non-PC technology into the first overunity device (it will still draw fuel from the tank). There will be a HP loss.

If your contemplating free power from the Worm Hole (or similar Si Fi) I can't comment ,

but if your talking a new diesel,the first antique advantage is only low pressure fuel, no 35,00 psi pumps and extreme filtering needed.

A leak would be a dribble or squirt , not fully vaporized , ready to explode vapor.

Second joy is the brain box does not exist , there fore a lightning strike , or even side strike a mile away will not stop the boat dead , till a $10K box is shipped in from someplace.

Efficiency is a delight for the complex modern stuff , but the ability to keep operating , even half dead , is worth a bit of fuel to most rec boaters.

Even the big guy$ get tired of $10K box R&R.

FF

 

Is that how much my box is going to cost when it goes out? (Volvo D9) Yuck! Mine doesn't have high pressure fuel, either, as it is unit injector. The common rail ones are the real high pressure ones, right?

 

Volvo D9

Car and truck transplants may have boxes at junk yards.

 

OK but the water has to come from somewhere and if its getting drawn from the atmosphere or condensed within the tank atmosphere then replacing that atmosphere with some inert gas might help prevent H2O infiltration would it not. Just sayin cause if the moisture laden atmosphere is prevented from entering the tank in the first place then its kinda hard for the water to get in in the first place

I think
basically I ripped that last out of my ***
waters gotta come from somewhere right
if its not already in the fuel then ?

same with the bacterial issue
stuff needs water to survive if I remember right otherwise it just crystallizes and waits

 

If you think the only water in your fuel is from air & condensation, simply switch to a bladder tank.

FF

 

There may be some drops from condensation as well, but most of the water is sold as diesel fuel (or gasoline) at the gas station. Their large tanks are dug in and pull in moist air for every gallon pumped out.
Being the morning's first customer can sometimes mean receiving half a gallon of water, especially in the summer season when students are employed and sales are booming.

 

maybe BUT for over 70 years than ran without problems ( no need to be bled ever) with their inbuilt large flow fuel system 'fuel polishing' as people call it now, helped to remove all the water/crap and helped keep tanks clean.
Are owners having a more maintenance free time today??

 

I wanted to give a update to solving some of my problems. I did put my return line on the primary filter head. The engine operates just fine. I have about 100 hours on the engine since moving the line from the tank to the filter head. These are working hours pulling a net. No problems (yet). No obvious signs of loss of HP. I am even on the same filter(s) since the change over.

As far as the tank cleaning, I have not solved that problem yet. Due to the time of the year and the money to be made. I made that a winter project.

I will report back.

Thanks everyone for the suggestions and comments so far.

 

just remember that part of the reason for more fuel to the Injectors than required to supply the running horsepower is, to cool the Injector Tips and to cool and lubricate the High Pressure side of the Injector Pump. If you return Hot Fuel directly into the Low Pressure side of the Injector Pump, you are defeating the secondary purpose of the extra fuel flow. Cold Fuel lubricates better than Hot Fuel.

 

to cool and lubricate the High Pressure side of the Injector Pump. If you return Hot Fuel directly into the Low Pressure side of the Injector Pump, you are defeating the secondary purpose of the extra fuel flow. Cold Fuel lubricates better than Hot Fuel.
__________________

Not on a DD , the "injector pump " IS the injector.

FF