Tide rising in the sump on a diesel,

[Wagger]

I am posting this for the benefit of others who may be mystified as to why the sump oil level rises when it is not caused by water leaks.

I have had two experiences of the sump oil level increasing in a diesel car. First one was almost catastrophic back in 2013. The HP fuel pump seal gave way and the car ran on its sump oil/diesel mixture. The only way to stop the car was to brake it it top gear without declutching. It ran at full power for a quarter of a mile before I found a long layby. The car did another 100k miles after just a pump change. BMW 3 litre straight six diesel, M57. It was still going strong when reversed into by a van driver, writing it off at 270k miles.

Therefore, I monitor my 520D M47 really often and noticed the level had risen recently. I pumped half a litre out and the level remained the same for over 1000 miles. However, last week it rose again.

Reading other forums suggested that it could be due to the system initiating a DPF regen. Apparently, it over-fuels when running in order to burn off deposits in the DPF.

Today, I drained the sump and re-filled with fresh oil because the oil could have contained up to 10% diesel. The engine still sounded ok before and after. I will continue to monitor the level before every journey and try not to do short trips. They are not good for modern diesels.

I have no idea how to stop the thing doing a regen just before I turn into urban areas. One should be able to initate it when on a long stretch of motorway in ideal circumstances.

Any discussion is welcome.

 

[AndyTV8]

The PITA of modern DPF’s. Some cars are better suited to the regen process than others to ensure it has a good chance of completing. In all honesty, the only real fix for vehicles which struggle with DPF regens is to delete and map-out the damn thing, it costs considerably less than a new DPF plus EGR plumbing, however you do run an elevated (albeit small) risk at MoT time.

the JLR community suffer very badly from this issue.

...Andy 

Edited Monday at 16:43 by AndyTV8

[Wagger]

1 hour ago, AndyTV8 said:

The PITA of modern DPF’s. Some cars are better suited to the regen process than others to ensure it has a good chance of completing. In all honesty, the only real fix for vehicles which struggle with DPF regens is to delete and map-out the damn thing, it costs considerably less than a new DPF plus EGR plumbing, however you do run an elevated (albeit small) risk at MoT time.

the JLR community suffer very badly from this issue.

...Andy 

Thanks Andy. I'll get my son who is a JLR fan on it with his laptop next time he is down here. I am expecting a big MOT this year after 5 straight throughs. There are many things not quite right with the car, now almost 17 years old. What next, if beyond economical repair? An even older petrol car maybe.

[Straightsix]

My wife had an 08 Fiat 500 diesel which she absolutely loved. Sadly this engine also suffered with increased sump oil level issues , several trips to the local garage failed to sort it, so part exchanged the car in the end.

Thankfully my 330d e46 doesn’t suffer with it.

[Wagger]

6 hours ago, Straightsix said:

My wife had an 08 Fiat 500 diesel which she absolutely loved. Sadly this engine also suffered with increased sump oil level issues , several trips to the local garage failed to sort it, so part exchanged the car in the end.

Thankfully my 330d e46 doesn’t suffer with it.

Ah, but it was my E46 330D Touring that had a pump seal failure. No warning with oil level. It just flooded the engine so that it ran at full power. Had it been an auto, it would have been terminal. keep an eye on it as it is a terrifying experience.

[Colin Lindsay]

Happened an alarming number of times locally due to smuggled and treated diesel ruining the pumps, ending up in the sump, and ultimately overfilling and going on fire. Even 'reputable' filling stations were using the smuggled stuff and it was commonplace to see them closed down and the pumps taped off or taken away by customs, so you never knew what quality of fuel you'd get. Around 2001 the average price of a replacement diesel pump here was £1000. That's no exaggeration; I paid £800 for a replacement for my wife's Rover 25 and was lucky to get it, as it came from a breaker's over 80 miles away. They were just not available and the waiting lists were huge.

[Straightsix]

22 hours ago, Wagger said:

Ah, but it was my E46 330D Touring that had a pump seal failure. No warning with oil level. It just flooded the engine so that it ran at full power. Had it been an auto, it would have been terminal. keep an eye on it as it is a terrifying experience.

Oh Lordy! mine is an auto, and yes they do get up and go.

I wasn’t aware of this problem and trust it’s not common on these!

[PeteH]

Runaway diesels?. Very good collegue of mine, Sadly deceased, (yet another Prostate Cancer victim) circa 1980/90`s was Chief Engineer on a Car Carrier, Geat big V12 Marine diesel engine, one of two, coupled by viscous coupling to the Main Shaft and normally run aprox; 600rpm, went "over rev`s". and could not be stopped by the normal "kill". Cause was a fractured hydraulic oil pipe spraying onto the Turbo charger air intake!!. He and another engineer managed to get a Tarpaulin over the intake by which time the rpm`s where as they say "off the clock". Limped to Grimsby on one engine and the manufacturers where on board for over week to check all the fasteners and bearings et-al, Before Lloyds would clear them to sail. The consequences of that shedding several 500Kg(ish) piston/rod`s etc, don`t bear imagining. Brown trousers all round time!.

Pete

Edited 20 hours ago by PeteH

[johny]

Brave men!

[Peter Truman]

Not my normal area of responsibility but once every 5 weeks I was the out of hours duty engineer for all disciplines water, sewer, drainage, for Melbourne Water, during one easter around 45 years ago, the hols were 5 days here I got a callout re our Eastern sewer treatment plant where there had been a major failure of one of the massive V12 engines that drove the power generators putting electricity back into the grid using the sewer gas's, one con rod had punched a hole thro the crank case. These engines were massive probably 15 to 20 ft long of some American origin how many thousands of HP I cannot remember, the crankcase was repaired by stitching with lock screws (Metalock) and it is still working daily to this day 40 years on, mind you the repair took 6 months, the engine was one of 6 at the plant. My job was obviously emergency response and get the emergency crews techo's to check the plant isolate the failed engine and get power generation back up, being easter load on the grid was reduced as industry was shut down giving us some grace! 

[Pete Lewis]

end of the assy line , if some plonker over filled the oil bath air cleaner the Commer TS3 which always started with the least flick of the starter  would suck up the oil and run to destruction as the long through  rods that  held the side rocker shafts  would get stretched 

early engines could give a slight kick and you would take of  to find she was running backwards 

the chain driven blower and pump were replaced with gears with anti rotation built in .

Pete

 

[Wagger]

On 23/10/2024 at 20:51, Straightsix said:

Oh Lordy! mine is an auto, and yes they do get up and go.

I wasn’t aware of this problem and trust it’s not common on these!

To be fair, I had noticed a slight rise in sump level two weeks before the event. i was unaware of the cause back then. Just check the level weekly and take action if the problem shows up.

Fitting a 'Strangler' in the air intake will stop it. (Butterfly valve like an old fashioned 'Choke').