[Nickoss]

Hello Guys did anyone had any indication of fuel in the engine oil after oil change or time to time service?I am wondering since the principal of the dpf regeneration intervals says that if this procedure is not executed with success but an interruption would be occurred,then some quantity of fuel may go to the oil pan.which means oil would be diluted.In my town I've heard two of those examples with catastrophic consequences to the engine.Is that true?Any experience of anyone?I am terrified

[AlanHo]

It does not mention that in my owners manual.

[Phil №❶]

You don't need to be terrified, as I'm sure it would be a very rare occurrence.

I believe there is a warning lamp in the instruments and for fuel to mix in the oil pan, the warning must have been repeatedly ignored. As long as you allow the DPF to regenerate properly, you should never have any problems at all. If the light does appear, go to your dealer.

[Nickoss]

It does not mention that in my owners manual.

Of Course not.I know that mate,but look here Frequently Asked Questions | Honest John DPFs also have an 'active' cycle where additional fuel is injected into the combustion chambers to create hotter than normal exhaust gases to burn off particulates in the DPF. However, this does not always work, particularly if the car has done a high proportion of short runs from cold starts and instead of burning off the particulate the extra fuel can instead find its way into the engine sump, contaminating the lube oil and sometimes leading to such a rise in sump oil level that the engine can start to run uncontrollably on its sump oil and will self-destruct.

[AlanHo]

I don't understand that statement and do not see how it applies to how Hyundai have engineered the DPF system.

For the Hyundai system, during regeneration, extra fuel is injected into the cylinders part way down the firing stroke so that it burns as it passes through the turbo and into the DPF - thus increasing the DPF temperature to burn off the particulates.

The Hyundai regeneration cycle will only operate if the engine and exhaust is hot
Hence if you are pottering around at low speed and the engine is not hot enough, it will not invoke the regeneration cycle.  The consequence of this is that the particulates will continue to build up in the DPF until the engine is hot enough and the speed fast enough for the regeneration cycle to operate.

Continuous stop/start low speed driving will delay the regeneration cycle and the DPF will become over-loaded with particulates causing the warning light to flash. This tells you that it is necessary to take the car on a 20 minute fast run to allow the regeneration cycle to operate which will normally stop the warning light from flashing. If the warning light continues to flash you will need to take the car to the dealer for them to attempt a forced regeneration.

I fail to see how extra fuel injected into the engine can cause the scare mongering warning on the Honest John site because the extra fuel is only ever injected into a Hyundai engine when it is hot enough to burn in the exhaust system as intended.

Perhaps other manufacturers have systems that ignore engine temperature and inject the extra fuel anyway - but in this case I would expect it to be propelled into the exhaust and cause a smoking exhaust and not find it way to the engine sump.

[Asterix]

I totally agree with Alan.

If you have so many regenerations interrupted, the DPF will be stuffed long time before there will be fuel in the oil. I does take a massive amount of fuel to overfill the engine.

What you have found at Honest John is a load of bullsh*t and only serve to scare people, but for what purpose...

[Lakes]

Hello Nic, well i have not studied the Hyundai DPF system or the possibility's of fuel in oil when driving short distance & motor not runing for long period.
but it does not worry me as oil is designed to handle that. it happens in petrol motors too or any motor. but Hyundais come with 5 year warranty so why worry just check dip stick once a week & just drive it.

[Phil №❶]

I would disregard the dishonest john article entirely.

The cause of runaway engines is due to turbo oil seal failure, where the ACTUAL engine oil becomes the engine's fuel and the motor will self destruct. It is very rare for this to happen, but it can. I'm fairly certain the Hy engines are fitted with an air cut off solenoid to kill the engine, by simply turning the key off.

There are thousands of Hy Diesel owners enjoying our cars every day, you need to as well, Nickoss

[Phil №❶]

it does not worry me as oil is designed to handle that. it happens in petrol motors too or any motor. but Hyundais come with 5 year warranty so why worry just check dip stick once a week & just drive it.

Quite right Lakes.

Actually it happens far more in a petrol engine due to incomplete combustion of fuel on every firing stroke. A spark is required to instigate ignition, which then rapidly propagates throughout the combustion chamber, however, some fuel is not burnt. In a Diesel, due to ignition of fuel by compression heat, no matter where the fuel is in the chamber, it ignites and burns, there is no propagation of flame. This is why Diesels knock at idle. As the fuel is all burnt, there is no fuel present in the oil.  There can be a small amount of blow by, due to the high compression developed in the combustion chamber.

[Lakes]

nic honest John must be talking about diesel's in general , not Hyundai . my two Hyundai's have both had a vacuum operated butterfly ( throttle body ) to shut air off on the intake manifold. most diesels don't have this , they just shut fuel off , mine shuts both fuel & air off when motor turned off. this would stop that dieseling effect where motor takes fuel & oil from the sump till it runs out of oil. so stop worrying.

thats what it is Phil , but its not a turbo Diesel problem even old non turbo Diesel's could do it, they say never leave the old diesel's in gear just use hand brake, as if they get hit or pushed they could start runing from motor turning over. not to say this is dieseling but just saying they are different to petrol in that respect.

[Nickoss]

Thank you guys for your encourage replies,But still here in Greece I know 3 occasions of that symptom on Hyundai I20 with the 1.1 diesel engine.And yesterday I just take a look of my engine oil level and it was some clicks over the F mark.Should I worry now?And what if that level goes more?Could that effect the engine?My clock says now 4800km and I changed the oil on 4500Km

[Asterix]

If it's only 300 km since you've changed the oil and there over the F mark, then someone have put too much oil on the engine.

If you changed the oil yourself, then suck up the extra oil or empty the oil and refill until F mark.

If your dealer changed the oil, take the car to them, let the engine off for minimum 10 mins before checking the oillevel. If too much, ask them to remove whatever amount of oil there's too much.

How much oil was filled in the engine at the service...

I change the oil myself and use 5,0 liters when changing oil and filter. That hits the F mark very well.

[Asterix]

Hi Nickoss

I found an old post of yours.

Initial Results - GD Crdi manual

It's from December 2012 where you say your car have 420 km on the odo, and now, one year later you only have 4800 km on odo.

4800 km a year is not right for a diesel unless you only drive when doing long trips. If you do only short trips (less than 15 km) and only town driving, then I think you have the wrong car, especially since the car have the DPF.

I would also be worried about condensation in the oil. You can see that if there's a white mayonaise-like substance on the underside of the oil filler cap.
If you have this there could be water in the oil instead. If that's the case, the water will evaporate when the engine gets a long trip where it gets hot long time enough.

[Eureka]

I remember reading in a newspaper's motoring lift-out (2 - 3 - 4 years ago?) of a concern over fuel getting into the sump.  It could have been the Mazda CX-5 diesel, or perhaps something else.     

[Nickoss]

Hi Nickoss

I found an old post of yours.

Initial Results - GD Crdi manual

It's from December 2012 where you say your car have 420 km on the odo, and now, one year later you only have 4800 km on odo.

4800 km a year is not right for a diesel unless you only drive when doing long trips. If you do only short trips (less than 15 km) and only town driving, then I think you have the wrong car, especially since the car have the DPF.

I would also be worried about condensation in the oil. You can see that if there's a white mayonaise-like substance on the underside of the oil filler cap.
If you have this there could be water in the oil instead. If that's the case, the water will evaporate when the engine gets a long trip where it gets hot long time enough.

Thank you Asterix.That is right,as I said back in that time we do not do long trips since we bought that car indeed.The reason I chose diesel was 1:none of the dealers here gave the right picture to their customers(like myself)2:the specific car I30 was in a real bargain price for a diesel version.EX.(Opel corsa 1.3 5MT diesel 16.000euro,Toyota Yaris 1.4 diesel16.000 while Hyundai's Astra or Auris,I30 1.4 diesel 6MT 15.000euro).and the price of diesel per litter was cheaper than petrol.Even taxi drivers told me that is the best choice,but after all none of their car at the specific moment was equipped with DPF.The funny thing is that a lot of them still don't know what dpf is :confused:Then I found you guys to find the truth 
small town short distances

One more thing Asterix, condensation in the oil,How does it formed?If I see that white thing on the underside of the oil cap,Would it be my fault?I mean should I be aware of something?

[Dazzler]

Hopefully it will be ok Nickoss

If it is only a few millimetres above the maximum mark on the dipstick that shouldn't do any harm.

If it is a centimetre or two that is a different matter..

[Phil №❶]

Diesel is a hydrocarbon, so during the process of combustion, water is produced. This is normally not evident when the car reaches operating temperature, as the water vapor remains in a gaseous state, but at ALL times, it IS being produced. Like your breath on a cold day, you can see the moisture, but the same amount of moisture is also produced on a hot day but you can't see it.

My advice to you, is to begin doing weekly drives of at least 20 minutes and at a reasonable speed to boil off any water that is in your oil. Check your oil after each trip and top up if necessary.

[Asterix]

The white thing under the oil cap is only there because the car do all those short trips.

If you follow Phil's advice and give the car a good run once a week it will disappear again

Hopefully it will be ok Nickoss

If it is only a few millimetres above the maximum mark on the dipstick that shouldn't do any harm.

If it is a centimetre or two that is a different matter..

Agree with Dazz about the oil level.

[Nickoss]

Merry Christmas to all you Guys!Yesterday I took a look on the engine oil level and as I Wrote some days ago it was 1cm over the F mark.So,Just because I don't remember if I did check the oil level exactly after the oil change in the garage,and in order to be calmed I did remove with a slim hose and a 60ml SYRINGE the extra oil, pouring it to a clean bottle.I did pump out several times.And in time to time I was checking the level to be correct!
The result was to pump out 450ml of oil in order to correct the level!Now I will keep an eye on it to see if it will raise again,I hope not!But another thing I saw was that the oil was darker than it is when new,even after 400 km...which some say that it is normal in diesels

[AlanHo]

Dark oil in a diesel, even shortly after an oil change, is nothing to worry about.

[Phil №❶]

However, if you removed 450 ml of oil and they presumably put the correct amount in, then 450 ml of old oil must have been remaining in the sump. 

Guess what, we had our car serviced last week. I supplied 5lt of oil and one of the comments was that it was 300ml short supplied oil, no extra oil was supplied. Why, when I arrive home, is the car is overfilled with oil.

Oh, and the plastic cap for the radiator fluid exchange was left in the engine bay too, just waiting to get caught up in something. 

I always check their work, every time.

[Asterix]

I hope you let them know, Phil.

They need to know their mistakes to make it better.

[Phil №❶]

The cap in the engine was shown to them next morning, by Marzipan. Apparently an apology was given, but in an aircraft, that can be a fatal error, just ask Misha. 

The oil, I will discuss at next service.

[agentr31]

I'm fairly certain the Hy engines are fitted with an air cut off solenoid to kill the engine, by simply turning the key off.

^ This

yes there is.

[tohis]

I've read about some breakdown incidents with older Santa Fe's, caused by sudden massive fuel leak into the engine. In those cases the seal in the gear-driven high pressure fuel pump has broken, which will make the fuel flood inside to the engine, up to several litres per minute. It will not only dilute the engine oil, but also makes the crankcase pressure rise which will eventually lead the fuel and diluted oil burst into the intake manifold via the breather. If not causing a runaway, at least it will raise burning temperature too high, which in turn will rapidly destroy injectors and melt some aluminum from the pistons. All this can happen in few minutes, without any warning in advance.

The fuel pumps in newer CRDi's have double seals and a hole out between them, so in the case of broken seal the fuel will leak outside instead of into the engine, which is still protected by that secondary seal.

To Nickoss: My dealer also put little too much oil into my i30. The oil level has been about 8 - 10 mm over the full mark, but I'm not too worried about that. Some guy at Finnish forum had it over 20 mm too high in his Kia Cee'd, but he didn't have any problems either.