Oil shearing vs fuel dilution

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Hi guys,

Can temporary fuel dilution induce permanent oil shearing?

Had an injector problem on my diesel, resulted in engine "making" oil (like 0,5cm above the max level on the oil gauge).
Had the injector fixed, and put like Highway 200Km on the engine since. Oil level lowered (now around the full mark) but engine still feels and sound weird when warmed up (really noisy and vibrating, like when oil is due for a change. Engine is "normal" until fully warmed up.

So I wonder, could the oil been "damaged" by fuel, even if it has mostly evaporate since?
The oil has around 1300Km on it (normal OCI 7500Km).
It is also possible that the engine has been damaged by the injector issue, but my money is on the oil since all is ok when cold.

Thanks in advance for any input
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Some of the fuel that got in has evaporated, but not all. So it has thinned the oil. Don't know how much.
And fuel is a good solvent, so if there was any sludge adhering to walls, it's probably being broken down and is loading up your filter.
Change the oil and filter ASAP.
Oil is cheap. Engines aren't.
 
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That's what common sense would dictate
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I'll change it asap. For once I put a more expensive oil than usual, That's just bad luck.
 
Originally Posted By: A_Harman
Some of the fuel that got in has evaporated, but not all.


Here's a typical distillation curve for diesel
distillation-profile.jpg


Probably half the fuel is still there, and as A_Harman says, it's thinned your oil.
 
There's been a bit of discussion on this topic regarding gasoline engines; not sure if the same holds true for diesels. In gas engines, the thought seems to be fuel damages viscosity index improves permanently. So a fuel dilution event reduces an oil's viscosity even if the fuel evaporates with further use.

Again, the chemistry with diesel fuel may be different, but my DI Honda showed a major viscosity decrease even with only 1% fuel dilution (assuming Blackstone can accurately measure this stuff, which I'm beginning to doubt).
 
Years back there were problems with injector seals. Maybe look for a TSB For your truck.
 
I read about gasoline damaging permanently viscosity improvers and was wondering the same thing about diesel, but looking at diesel evaporating temps, I think my sump is still full of diesel
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I realize I was a fool driving ~200Km with this "oil", but thought "meh, it's gasoline, it has already evaporated"...but it wasn't gasoline, old habits die hard!

The oil is the quite expensive Total Quartz 10W50, only ~1300Km on it. Maybe since it is full of diesel it can be reused as fuel for the car ? Lol joking because we have fuel shortage at the moment.
 
With DPF regeneration there is a lot of fuel dilution - the new Mitsubishi Triton engine has an ''X'' mark on the dipstick, above the level mark. If the oil level rises to the X mark you need to change the oil, as fuel dilution has raised the level.
 
10w50 is pretty stout, and you don't need to run at boiling point of Diesel to get rid of it ... Even at lower temps will eventually evaporate, slowly, but will. Now, if it keep feeding up dilution, you can't make it quick enough. The noise could be result of the extra cleaning and changing the oil won't make a difference. Now, caution dictates at least a partial change, like 50%.
 
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I'm not sure if the "diesoil" really cleaned since the engine is fairly clean, and the oil is not very black (it has only 1300Km and the EGR is deleted), but as many say, caution dictate oil change.

Since partial oil change is often messy, and since the weather was very nice tonight, I changed the oil and the filter. Even cold, it was very watery, so I guess there's still plenty of fuel in it.

The new oil made the car less noisy, I haven't put more than a few Km on it and haven't fully warmed the engine, but so far so good.

Now is there something to do with the old oil? Filtering, heating in a pan to help fuel evaporate, or just recycle it?
 
Originally Posted By: Silk
With DPF regeneration there is a lot of fuel dilution - the new Mitsubishi Triton engine has an ''X'' mark on the dipstick, above the level mark. If the oil level rises to the X mark you need to change the oil, as fuel dilution has raised the level.


Depends on the engine. Some introduce extra fuel to initiate a DPF burn like you assert, but some actually introduce the fuel down stream at the DPF. In that case, no fuel dilution issue. Anymore, with the new emissions stuff. it is almost insane to not do at least random occasional used oil sample testing.
 
Change oil, bio diesel is nice but it's cleaning power at 20% is a bit hardcore when engine is ok, with a fuel injector issue ? The oil is diluted , send it for analysis you ll know for sure
 
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