Anyone have any idea how much water is acceptable to run in diesel?
With condensation, unknown tank sources (are there really filters in the fuel lines? Anyone ever see one get changed?) etc a lot of water has to be getting through.
I know when my truck wouldn't start one day, I drained 7gals of water out of the fuel tank. Dumped out filter cans and put in new filters. Let it sit over night and it started up and ran great the next day. Less water is better than more water. I have also been told that water injected into a running motor will destroy the injector.
I have also been told that water injected into a running motor will destroy the injector.
Water will destroy an IP or injector quickly.
When the injector or plunger in the IP compresses the fuel it does it very quickly. Mix in water and under the pressure and heat the water will flash to steam. Steam + no lubrication, no "cushion" and the will quickly destroy your fuel system parts.
In a hydraulic system, like a backhoe's, water is really bad because it is much thinner than the hydraulic oil, and droplets entrained in the oil go rocketing past the seats on the control valves, and take a bit of seat material (usually steel) along with them... think: water jet cutting machine.
I would think that much the same thing happens when the water goes past the valve seat in the injector nozzle, and through the nozzle holes itself. Erosion is not a good thing in a nozzle.
Gasoline boils between 100F and 250F, starting much lower than water, and yet the designers of the MF engines talk about it flowing as a stream through the injector and into the combustion chamber... I think the injectors are cooled enough by the block and the fuel to prevent flash boiling.... but I am not sure of this at all.
An old school diesel mechanic once told me that if water got past the IP it could cause the tip of the fuel injector to blow off (the steam thing) and inject unatomized fuel into the cylinder....this often results in a hole being melted into the piston.
I had it happen to a 400 Cummins in a Peterbuilt I was driving.....the piston had a hole the size of my little finger in it.
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My karma ran over your dogma.
Wreckerman's rules of the road (and living in general)
pressurize a liquid up to 1,400 psi.
EDIT: This statement probably isn't 100% correct. Please feel free to correct me.
3000 psi
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James
1 Bobbed 5 ton with lockers in rear and W/W
30 Outher Military Trucks
4 Military Cranes
3 Military semitrailers
2 Military expandable semitrailers
3 military gens. 3k 5k 10k
And storage of to many Military parts that it might be a sin.
Go for zero tolerance.
Alcohol will mix with water and may render small amounts of water harmless (one side effect of homemade biodiesel that may have some residue of methanol).
Drain water trap/filters often.
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Bjorn
MEP-018A (needs new generator head)
Avatar: XM757 in OK prepared for 1,000 mile trip home. Part of 6,000 mile journey in 2006.
1968 M49A2C modified with 1960 M756A2 truck bed and 1975 HIAB 765A knuckleboom, exhaust brake and more. (SOLD)
1969 Ford XM757 8x8, 5-ton Pershing 1A truck tractor...the "improved MV".
"Some things can't be made better, just differently......a lot of things actually"
An old school diesel mechanic once told me that if water got past the IP it could cause the tip of the fuel injector to blow off (the steam thing)...
Interesting...
I spent about 2 hours last night trying to get to the root of the water in fuel issue as it applies to C-I engines, and I came up with "theories" that traveled in two different directions:
The fuel additive companies (Stanadyne, etal), and the engineering textbooks on my shelf, all seemed to be interested in the abrasive qualities of water in the 10 to 40 micron particle size range, and the corrosive properties of water in general, and the hear-say group (not meant derisively: my buddy the mechanic, this chief I knew, somebody once told me...) seemed to like the idea that water blew the tips off of injectors.
Everyone likes stories of explosions, so I guess exploding injector tips fit in that category.
The "fuel experts" (additive companies...) concentrated on corrosion caused by free water droplets, water's (in quantity) ability to stop an engine dead by preventing fuel from getting into the cylinder, and water's abrasive qualities when the droplets are the right size, and under hydraulic system pressures. Their cure to water was to fracture the water droplets to such a small size that they are no longer abrasive, and will pass out the tailpipe as steam.
As to the hear-say group's conjecture that water blows the tips off of the injectors:
We all have quite a bit of experience with water and steam, whether we know it or not. The pressure cooker your mother used demonstrated an interesting property of water and steam and that is it will increase in temperature when you allow it to increase in pressure... that is to say that if you keep water under pressure, the temperature needed to turn it into steam will increase greatly.
A fuel injector nozzle has a valve in it that is designed to hold the nozzle shut until the pressure rises to the pop-off pressure where the valve spontaneously opens, and then as the pressure again drops, it will seal off the nozzle (to prevent drips...). If steam were to form in the injector, it would simply cause the valve to pop-open and release the pressure.... right?
In any case, my study did quite a lot to enforce my belief that the only problems with water in your fuel are corrosion, abrasion, and possibly the complete elimination of combustion (all water).
How much water is ok?
