Adding 2 stoke oil to diesel fuel

[The Mirror Man]

Does anyone do this? It's common practice with Rover 75 CDT owners. I've done it myself for many years and it seems to make the engine run smoother.

I was wondering if Mercedes CDI drivers do the same.

 

[Clivefa]

Does anyone do this? It's common practice with Rover 75 CDT owners. I've done it myself for many years and it seems to make the engine run smoother.

I was wondering if Mercedes CDI drivers do the same.

I have - but use mineral based oil, not synthetic or semi-synthetic.
B-i-L used it in his disco and also reported smoother running.

 

[The Mirror Man]

I have - but use mineral based oil, not synthetic or semi-synthetic.
B-i-L used it in his disco and also reported smoother running.

B-i-L ?

Yes, mineral 2 stroke oil. I bet i've used it for 50k miles without a problem. And I notice the difference when I forget to add it. Smoother, quieter and a bit more umph.

I don't want to put it in the Merc though until I know it will be okay.

 

[CabrioDave]

What ratio of oil:diesel are we talking about, here?

 

[stwat]

B i l= brother in law.

There are loads of threads about it. It's a shame the search doesn't seem to be working.

 

[Deleted member 6183]

B i l= brother in law.

There are loads of threads about it. It's a shame the search doesn't seem to be working.

Lots of threads about Brothers in law or 2 stroke oil?

 

[The Mirror Man]

About 200-250 ml per tankful. On a Rover 75 that's about 50lts.

 

[190]

It shouldn't be any old 2 stroke oil. It needs to be TCW3 spec which is ashless. Using ordinary 2 stroke oil wouldn't be a good for the DPF especially having gone to the trouble of using low SAPs engine oil.

Must get a little expensive at a ratio of 1:200 The dosage used for petrol engines is only 1:640

 

[CabrioDave]

Must get a little expensive at a ratio of 1:200 The dosage used for petrol engines is only 1:640

How times have changed. My 1951 and 1965 Bond Minicars should be run on 1:16 and 1:20 respectively.
With modern oils, and a sense of guilt, I run both on a weaker mixture ... of 1:25

And yes, it makes the fuel very expensive!

 

[The Mirror Man]

It shouldn't be any old 2 stroke oil. It needs to be TCW3 spec which is ashless. Using ordinary 2 stroke oil wouldn't be a good for the DPF especially having gone to the trouble of using low SAPs engine oil.

Must get a little expensive at a ratio of 1:200 The dosage used for petrol engines is only 1:640

Is a quarter of a litre in 50 litres 1:200? I don't know. Can't remember how much I paid for the stuff but it wasn't much.

 

[The Mirror Man]

It shouldn't be any old 2 stroke oil. It needs to be TCW3 spec which is ashless. Using ordinary 2 stroke oil wouldn't be a good for the DPF especially having gone to the trouble of using low SAPs engine oil.

Must get a little expensive at a ratio of 1:200 The dosage used for petrol engines is only 1:640

Fair point about the DPF. That's why I asked really, I don't know these engines as a do the M47 in the Rovers. The BMW sourced M47 engine doesn't have a DPF. Does the 270CDI?

 

[Auto-mobile]

Also been told to use cooking oil (new)

 

[190]

I haven't used TCW3 in diesel but they say it adds lubricity to the fuel. I've only ever used it as a petrol additive and any lubricity it provides would be welcome to reduce wear in a carburated engine. They say it improves fuel economy but I can't say I've noticed any improvement nor can I see a mechanism that would produce it except that it's similar to an old fashioned upper cylinder lubricant like Redex.

The two effects I have positively experienced over 5 years use in my motorcycle are the detergent content acts to slowly clean up the combustion chambers over long term use and it somehow manages to smooth the combustion process and reduces any tendency for the engine to ping on 95 Ron fuel. Evidence for the cleaning effect is visual and I'm satisfied that anti pinging effect is real after switching back and forth from treated to untreated fuel several times.

So far I've shied away from using it in a car with a cat. If you do the sums it's like an engine burning 2 litres of oil over 10,000 miles. Not the end of the world perhaps as some engines use that much oil anyway without ill effects.

 

[mmfkf]

Hi Mirror Man,
did you find out much more or come to a decision ?
are you added it yet?
I have had a read through a number of posts and not many seem to be using 2sO although I am a fan I have only just bought a CDi
and
I don't have much 2sO left (actevo FC)

iirc none DPF can use FB if you have a DPF it must be FC and full synthetic FD is no good in either,
Does that sound right with your findings

 

[The Mirror Man]

Hi Mirror Man,
did you find out much more or come to a decision ?
are you added it yet?
I have had a read through a number of posts and not many seem to be using 2sO although I am a fan I have only just bought a CDi
and
I don't have much 2sO left (actevo FC)

iirc none DPF can use FB if you have a DPF it must be FC and full synthetic FD is no good in either,
Does that sound right with your findings

I haven't had time to look into this further matie. I just bought the cheapest mineral 2so and put 200-250ml into a tank full of diesel when I was running the Rover. As for DPF: I don't even know if my w211 has one .

 

[mmfkf]

Hi,
I have given the first dose to mine

250ml to 50L of fuel FC grade, I bought 5L of FC for £16 off the bay of fleas so even though mine has Not got DPF I can use the same 2sO in both cars

 

[The Mirror Man]

Hi,
I have given the first dose to mine

250ml to 50L of fuel FC grade, I bought 5L of FC for £16 off the bay of fleas so even though mine has Not got DPF I can use the same 2sO in both cars

Has it made any noticeable difference?

 

[moonloops]

Does anyone do this? It's common practice with Rover 75 CDT owners

Who the heck trusts anything that Rover 75 owners do ?

 

[kid-jensen]

Wasn't there a thread on here a while ago that said this was a VERY BAD idea?

Worse, it resulted in less power..

Or did I dream it?

So difficult to separate reality from fantasy these days....I blame working in Crawley.

 

[MancMike]

With RX8s which are petrol, it's very common to add some 2-stroke oil to the fuel. It helps the apex seals on the rotary engine to seal, in addition to the engine oil that's fed into the chamber to do the same job. The 2-stroke oil burns cleaner than the engine oil and the additional quantity of lubricating oil going in with the fuel made it run noticeably smoother, and more power was possible with some engines as it increased the seal with the chamber slightly, giving slightly better compression.

Diesel is already very oily, I can't imagine why you'd get additional benefits from 2-stroke in the diesel.