Is it ok to run a 25% diesel 75% oil mix in a 2.0D?

[5cilinder]

to save on oil analisys in the future do a simultanious blotterspot test on a koffiefilter with a drop of oil , the width of the outside fuelring is a measurement of the analysed % of dillution that the lab analysed so that in the future you have a benchmark of dillution % of the oil smaller ring is less than 10% wider is more

Its quick and for free indication
http://www.machinerylubrication.com/...l-analysis-lab

Or take a labtube with a marble and measure the time to drop to the bottom with 2 viscosities fresh oil and the dilluted oil with the max% you desire
so that when the time stays longer than the dilluted sample the viscosity is within tollerance

What i said before dilluted oil cant be prefented with a dpf just change it more often with a heavier grade oil and it should be ok, what you also can do to make sure it is function normal is to connect the torque app to the ecu and monitor the egr valve and throttle than you can monitor how often and how long it regenerates if its too much than further investigation on sooth produktion is needed the egr valve closes with regeneration and the throttle will almost close to 20%

[skyship007]

Originally Posted by 5cilinder

That graph isnt a perfect practical example , because this was dilluted for hours in one go
Normally its 15 minutes regeneration in 400 miles or so
Ive seen a graph with a car on a testbench the dilution was a flattened out curve when the dillution became 15 % coulden't find it do to link it
The temp in the graph used above is 85c its in red on the right

Sumpwarmup isnt needed this engine has a coolant oil heat exchanger sot roughly the coolant temp is also the oiltemp
So even if you warmed up only the sump the heatexchanger will cool it quickly down to the at first cold coolanttemp
If you want to heat something get a coolantheater , also availible from volvo or aftermarket ,then the oil is also instantly heated the moment the engines runs

A full main block pre heater will cost about 350 quid, but the installation cost is more significant. It's easy for the OEM to install one with the engine out, but quite a plumbing task with it in, although I don't know if there is more room around the V50 engine than the V40 I have. The heat from a sump heater rises and will warm the block, but it won't warm the coolant in the radiator or heater, so the full block heater is better, but as with most things it is a matter of how much you want to spend (100 quid and an easy DIY job, or 350 plus perhaps 3 hours labour with the car up on a proper lift, so might cost 500 quid total).

Stunned to see such high fuel contamination figures, it's odd that those high figures are not showing up in too many UOA results I've seen.

[chrisdc]

Hi 5cilinder,

Thank you also for your contribution. I did base my predictions on a linear assumption, but as you've pointed out, this is not necessarily the case. I'm going to do as you and others have suggested and use a thicker oil. Our temperature rarely drops to 0 degrees, even in the middle of winter. Perhaps a couple of degree below, but that's rare, at least on the coast where I live.

A chemist friend of mine has also pointed out like you have, that diesel in itself is also a lubricant. I just had no idea until this last unscheduled service that the oil level had become dangerously high. I have to say I never check my oil because I always stick to the dealer service schedule and in my opinion, if an engine needs oil in-between services, it is worn out and should be scrapped.

Furthermore, when I bought my new Mercedes SLK, I was told to never add oil because the engine measures the oil quality and the ECU bases the services on this measurement. If you add oil, the oil quality improves and the service is “chased away” into the future. I realise my Volvo does not use this system and I will be keeping a close watch on the oil level from now on.

Thank you for also pointing out that the diesel also cleans the engine. With my levels of dilution, I must have a very clean engine indeed!

[5cilinder]

10% is "normal" dillution with DPF engines who utilize after injection instead of an extra injector in the catalist
Main problem is the usage of biodiesel (perfect lubrication for injectors and pump) it won evaporite like normal diesel does and it wil polymerise if its too long in the sump
Now my older diesels non dpf diesels needed extra oil refills to make up for the burned oil
With dpf you save on that oil due to the dillution , if you shorten the drain intervals you basicly will use the same quantity on oil in total but will have a cleaner engine due to the prevention of the dillution problem you have a benefit of cleaner oil due to the shorter draininterval
IM no dpf fan i rather didnt have them or a more better technical solution with an extra injector etc, but when you realise what is happening and why you will be able to prevent problems with proper (cheaper) heavier oil and shorter drain intervals
The diy analyse technics are not precies behind the decimal but they are free and usable as a practical indicator

Buy this vacuumpump and drain the oil trough the dipstick its quicker than lifting and draining , but you dont need a lift or garage
Also the amount sucked out is the amount to refill without guessing and dipping afterworths
http://www.pelapumps.co.uk/

Even if you want to drain it a a regular draininterval at the garage you can partly refresh your oil with the pump in between the drainintervals to keep your dillution in check

Furthermore, when I bought my new Mercedes SLK, I was told to never add oil because the engine measures the oil quality and the ECU bases the services on this measurement. If you add oil, the oil quality improves and the service is “chased away” into the future. I realise my Volvo does not use this system and I will be keeping a close watch on the oil level from now on.

Whats wrong to add oil when it drops to low? and indeed fresh oil will boost up the oilquality temporarly , and so what if the service is "chased away"?
Its logical! and desirable
With my old diesel when they used a bit more oil i also lengthed my drainintervals due to that principle of the partly oilrefreshments in between, no mercedes ecu needed!
Probably that bad advice (with the risk in running to low oillevel)was to sell you more oil with earlier services that completely makes the qualitymeter obsolete if you ignore it

[chrisdc]

Originally Posted by skyship007

A full main block pre heater will cost about 350 quid, but the installation cost is more significant. It's easy for the OEM to install one with the engine out, but quite a plumbing task with it in, although I don't know if there is more room around the V50 engine than the V40 I have. The heat from a sump heater rises and will warm the block, but it won't warm the coolant in the radiator or heater, so the full block heater is better, but as with most things it is a matter of how much you want to spend (100 quid and an easy DIY job, or 350 plus perhaps 3 hours labour with the car up on a proper lift, so might cost 500 quid total).

Stunned to see such high fuel contamination figures, it's odd that those high figures are not showing up in too many UOA results I've seen.

With regard to engine heaters, i had never heard of them before i joined the forum. I doubt if there is a single car in SA fitted with one. It just doesn't get cold enough. My car usually reaches full operating temperature in less than 5km (which takes only a few minutes). But thank you for the suggestions. At the moment i don't use the car during the week, but i do like to make long trips on the weekend, which i believe is a good driving pattern for the DPF.

[5cilinder]

Buy a 20 pound bluetooth obd2 connecor and hook it up on your smartphone
It will exactly point out if you look at the rigth sensors how often and how long it will regenerate
It makes it even possible to know when the next one comes and anticipate with a planned highwaytrip , highwaytrips during regenerations will need less extra fuel to inject in the exhauststroke due to a higher base temp of the exhaustgas wich will dilute the oil less

Extra benefit of the bluetooth connector is when your engine wont start you can pull instantly (only enginerelated)faultcodes ond obiusly for free

[chrisdc]

Originally Posted by 5cilinder

Buy a 20 pound bluetooth obd2 connecor and hook it up on your smartphone
It will exactly point out if you look at the rigth sensors how often and how long it will regenerate
It makes it even possible to know when the next one comes and anticipate with a planned highwaytrip , highwaytrips during regenerations will need less extra fuel to inject in the exhauststroke due to a higher base temp of the exhaustgas wich will dilute the oil less

Extra benefit of the bluetooth connector is when your engine wont start you can pull instantly (only enginerelated)faultcodes ond obiusly for free

I would be very interested in purchasing such a device. Can you give me a model number to search for? One that you know will work with my model Volvo (V50). I do have a new smartphone so that part is taken care of.

[5cilinder]

You need to google for a good one , many look the same but are different (the cheap chinese ones)
Go to a shop and ask if you can try it at the shop and buy if it works

Android will work on bluetooth but with an apple you need a more expensive wifi connector
You need to pair it first too your phone and then let the torqueapp connect also the pro version is downloadable for free outside the google playstore

[skyship007]

Originally Posted by 5cilinder

to save on oil analisys in the future do a simultanious blotterspot test on a koffiefilter with a drop of oil , the width of the outside fuelring is a measurement of the analysed % of dillution that the lab analysed so that in the future you have a benchmark of dillution % of the oil smaller ring is less than 10% wider is more

Its quick and for free indication
http://www.machinerylubrication.com/...l-analysis-lab

Or take a labtube with a marble and measure the time to drop to the bottom with 2 viscosities fresh oil and the dilluted oil with the max% you desire
so that when the time stays longer than the dilluted sample the viscosity is within tollerance

What i said before dilluted oil cant be prefented with a dpf just change it more often with a heavier grade oil and it should be ok, what you also can do to make sure it is function normal is to connect the torque app to the ecu and monitor the egr valve and throttle than you can monitor how often and how long it regenerates if its too much than further investigation on sooth produktion is needed the egr valve closes with regeneration and the throttle will almost close to 20%

I think you will find that the accuracy of blotter tests is not too good. There are some fairly expensive portable oil analysis units available that can give a rough idea, but taking a sample and using a cheap lab will provide far more information.
Modern diesels can accept quite a wide range of oil viscosities, although it helps to use a top quality oil that includes lots of anti-wear, extreme pressure and friction modifiers to help when the oil film fails. The engines that will suffer the most are those used by drivers with big feet in hot climates.

If I had to suffer the presence of a DPF, I would be tempted to try adding some extra additives with a before and after UOA (Used oil analysis) to see if it helps the wear metal figures. I'm lucky enough to live only a few kilometers from the best commercial oil and fluids lab in Southern Germany and drink with a few of the oil gurus. The only oil additive that seems to improve figures when added to a major brand top of the range synthetic like Edge, is Liqui Moly Ceretec. It won't harm a DPF and contains Moly, Boron and Ceramic particles (The Moly helps reduce main bearing wear, the Boron helps with upper cylinder wear rates and the Ceramic particles fill in pitting or particle streak scratches). The 50K km figure they advertise is rubbish, as I've not seen a UOA with an effect after the OCI it was used in. The chaps I know think half a 300 ml bottle every oil change is a better idea. I will test that additive early next year, but I'm busy testing different oils and you can't change two things at the same time, without confusing the results.

Liqui moly is the only oil additives company I trust and they are very good at answering questions, also it's important not to add anything with extra Zinc compounds as it will foul the Cat and DPF faster. Most oil additives are at best a waste of money and at worst harmful, but LM are a real top tier engine oil company and I've seen enough UOA before and after results for VW TDI's to know it's worth looking at that particular additive.

PS. Machinery and Lube articles are good in general and there is one on thin vs thicks oils that is worth reading:
http://www.machinerylubrication.com/Read/518/motor-oils

One controversial point mentioned is that the reduction in Zinc based additives in modern C3 oils to reduce Cat and DPF ash related fouling might result in increased wear and that causes more oil to get burnt off, thus making the problem worse. It's hard to know if the school of thought that says engine wear is the priority and some more Zinc does help is correct or not. Some of the auto engineers I know that have DPF equipped cars don't use C3 oils, they are using B4's with more normal Zinc add levels. One chap uses Mobil 1 10/60 EP and a 20K km OCI for his V50 and the other is using Edge 0/40 with a 10K km oil only change (Full oil and filter change at 20K km).
I'm using Castrol TD 5/40 (C3) at present but only as an experiment before switching to Shell Helix Ultra Diesel 5/40 (B4) as it's real cheap in Germany, so it will be interesting to see how the figures change, as there is quite a difference between the 2 in Zinc levels.

[chrisdc]

Originally Posted by 5cilinder

10% is "normal" dillution with DPF engines who utilize after injection instead of an extra injector in the catalist
Main problem is the usage of biodiesel (perfect lubrication for injectors and pump) it won evaporite like normal diesel does and it wil polymerise if its too long in the sump
Now my older diesels non dpf diesels needed extra oil refills to make up for the burned oil
With dpf you save on that oil due to the dillution , if you shorten the drain intervals you basicly will use the same quantity on oil in total but will have a cleaner engine due to the prevention of the dillution problem you have a benefit of cleaner oil due to the shorter draininterval
IM no dpf fan i rather didnt have them or a more better technical solution with an extra injector etc, but when you realise what is happening and why you will be able to prevent problems with proper (cheaper) heavier oil and shorter drain intervals
The diy analyse technics are not precies behind the decimal but they are free and usable as a practical indicator

Buy this vacuumpump and drain the oil trough the dipstick its quicker than lifting and draining , but you dont need a lift or garage
Also the amount sucked out is the amount to refill without guessing and dipping afterworths
http://www.pelapumps.co.uk/

Even if you want to drain it a a regular draininterval at the garage you can partly refresh your oil with the pump in between the drainintervals to keep your dillution in check




Whats wrong to add oil when it drops to low? and indeed fresh oil will boost up the oilquality temporarly , and so what if the service is "chased away"?
Its logical! and desirable
With my old diesel when they used a bit more oil i also lengthed my drainintervals due to that principle of the partly oilrefreshments in between, no mercedes ecu needed!
Probably that bad advice (with the risk in running to low oillevel)was to sell you more oil with earlier services that completely makes the qualitymeter obsolete if you ignore it

I'm not so sure 10% dilution is normal simply because in my case the high oil level and / or poor condition of oil has triggered a code in the ECU (after only 4000km) resulting in a premature service. The car is supposed to go for 10,000km without any services in between. These are the terms of the warranty and maintenance plan. I did not choose the service intervals. Also, nowhere in the handbook does it say i must drain out oil at regular intervals to prevent damage to the engine. While the car was covered by the warranty, i could not touch it. (mechanically)

With regard to the Mercedes. This car was sold with a 6 year 120,000km maintenance plan. This was a (for me) very expensive car. I would not want to "chase away" the services because other items (brake fluid, filters, brake pads etc) are also changed at these services. It makes no difference to me financially because all costs are covered in advance for 6 years. If the oil were to drop to the point where the engine was damaged, Mercedes would fit a new engine, and as far as i'm concerned, it would be good riddance to the old one if it needed so much oil. In my opinion any significant oil consumption on a new or nearly new engine is unacceptable. Different story after 200,000km though.