Diesel mixed with oil [SOLVED]

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Chimo

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Hey guys I have Nissan Navara d40 st 2010 model with 130000 on the clock
Seems like I have diesel mixed in the oil?? As my dipstick is way past full by at least 2 litres, does anyone know what the problem might be any help would be very appreciated
Car is going into limp mode regularly
Also looking at my engine I have found a part that looks like it's covered in oil that comes from the fuel filter ? Wonder if this is related ?
 
It's usually an injector seal that causes fuel getting into the crankcase. It's extremely dangerous, because if enough diesel+oil can vapourise and make it unhindered out through the crankcase ventilation, you won't be able to shut your engine down and it won't govern itself - it will continue revving until it runs out of sump contents or detonates.

[YT]https://www.youtube.com/watch?v=3NRaqgab0_w[/YT]
 
not neccessary as the deisel has oil in its mix.
no

diesel in the engine oil will quickly destroy the turbo bearings. if still not fixed it will then destroy crank.cam, balance shafts etc bearings.

it would either be injection pump shaft seal or possible an injector dribbling.
edit: possibly spill tube connections.
 
Last edited:
why would deisel fuel ruin bearings ? as mentioned deisel has oil in it so there is a very small amount of lubrication for things like bearings. what keeps the fuel pump lubed ?
 
no

diesel in the engine oil will quickly destroy the turbo bearings. if still not fixed it will then destroy crank.cam, balance shafts etc bearings.

it would either be injection pump shaft seal or possible an injector dribbling.
edit: possibly spill tube connections.
Yep, especially with the ultra low sulphur diesel that we use these days...
 
why would deisel fuel ruin bearings ? as mentioned deisel has oil in it so there is a very small amount of lubrication for things like bearings. what keeps the fuel pump lubed ?
viscosity is one problem, its thins engine oil out.
the lube value of diesel is lower. keep in mind injection pumps are made of different material and different specs.
theres also the additive factor. oil is basically a base oil with additives. those additives need to be in the correct concentration to work correctly. to little or to much and they will not work effectively. they are matched to the types of forces and materials in the bearings.
reduce their concentration by diluting it with another oil and they won't work.
diesel has different additives designed for different things.

the other thing is what it does under high heat. especially with turbo's as the oil is primary cooling and is extremely hot.

in practice, i know of several zd30's that have suffered this fate, the turbo's are generally the first to fail when you have engine oil contaminated with diesel fuel.
one blew two turbo's then the engine. the problem was fault in the injector return, which being under the rocker cover meant fuel leaked into the engine oil.
 
Hey guys thanks for the feedback much appreciated
So I ended up taking it to a local mechanic, he said it has something to do with the injectors so he has pullled out my injectors and has found one of the seals on the injector to be stuffed
He has told me to drive it for a week and keep an eye on the oil level
Hopefully all fixed fingers crossed
 

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