Adding two-stroke oil on fill-up (diesels only)

[Scoob]

Hi all,

I was wondering how many of you are familiar with using Two-Stroke oil as an additive in Mercedes Diesel engines? I've had discussions on this subject on other forums, branching off from a general additives discussion. My Focus was the car concerned at the time. As a result, we (well I) did an experiment adding a 200ml shot of two-stroke oil each fill-up.

This had the effect of seeing the car run cleaner (less black smoke when initially pressing the throttle) and noticably quieter operation. Having done this for months, the one time I forgot was quite shocking, right away my car was noisier and felt less refined.

Many stated that the two-stroke oil would aid lubricating things like the fuel pump and injectors, something the newer low-sulphur fuels were not quite so good at. This, in theory, would promote longevity.

Now, moving forward, with more modern Mercedes diesels with DPF's, is this technique still valid, or do people here use other additives?

Note: the two-stroke oil used was good, mineral low-ash stuff - which actually burns far cleaner than the diesel fuel its self.

So, in summary, adding a little two-stroke oil each fill up in my older 2004 1.8 focus diesel seemed to make it run nicer. No down-sides observed.

Thoughts?

Scoob.

 

[tode]

Which 2 stroke oil did you use ? And what was its ash content ?

 

[Scoob]

It was a Halfords branded low-ash - I'd need to check the bottle to be sure, but I've left it in the Focus - which I parked up elsewhere today.

Scoob.

 

[tode]

Would be interesred to know the ash content - a while back I was looking at the specs of "low ash" oils, and in fact the content varies enormously.

 

[Scoob]

Would be interesred to know the ash content - a while back I was looking at the specs of "low ash" oils, and in fact the content varies enormously.

Sure, will get back to you on that.

Scoob.

 

[Scoob]

Hi,

Think I must have recycled the old bottle. I did a quick Google, and I think this is the stuff I'm using. Rather light on details, but it appears to have worked well.

Still unsure if this is suitable for DPF equipped diesel or not. The question did come up before, but was never really addressed on the original thread.

Scoob.

 

[mej]

I've been doing this since Feb 2012 (14000 miles) and agree it seems to make for a smoother engine. Much chat on this on Land Rover forums. My car (S211 220Cdi) isn't DPF though. The consensus on the LR forum was to use mineral, not synthetic 2 stroke. I use Waitrose's product, which comes in handy 500ml bottles and I add 250ml to each refill of around 60l, or just under 1/2% of additive. I have kept a log of consumption and can see no evident effect on mpg.

 

[cleverdicky]

Would normal vegetable oil work the same. Its light enough.

 

[Scoob]

Certainly mineral all the way. Worked wonders with my somewhat agricultural-sounding Focus. I think I will avoid initially with the Merc due to DPF, but will do some more research.

I think having a word with the GAD guys might be an idea & get their take on it.

Note: One thing I did find with the Focus... Using GOOD fuel, so Shell V-Power Diesel for example, my car would be quieter and smoother to drive. It was noticably less so with Supermarket Diesel, however, adding two-stroke would see the Supermarket fuel behaving more like the good stuff. I guess the additives that the more premium brands add are doing something.

Scoob.

 

[Scoob]

Would normal vegetable oil work the same. Its light enough.

I think not. Veg oils can leave nasty deposits. In theory a diesel can run just on veg oil, but the pumps and injectors can have trouble with it. traditionally older, more simplistic, diesels can run on the stuff unmodified, assuming a somewhat over-engineered fuel pump to cater for the higher viscosity of the veg oil. I have read reports of white deposits that can eventually kill the injectors / pump even though things seem fine initially. Reckon it's a little too risky to experiment on a modern diesel.

It used to be that veg oil, but chemically thinned with a little additive, worked well. I will have to review my prior reseach.

Scoob.

 

[mej]

Surely you're into a version of the 'sunflower/fish and chip shop oil as fuel' debate if you go with veg oils?

 

[denchen]

Ive been adding 2 stroke oil in my last C270 and my latest C200 for about the last 3 or so years now. I have no records but i believe the engine runs much smoother, quieter and I have not had any problems. I must admit I don`t measure how much goes in I just guess to what I think is about right to give the diesel a bit of help. As a rule I usually go for the cheapest supermarket fuel as I go for maximum miles per pound as I`ve passed my boy racer years but still don`t hang around on open roads.

 

[tode]

If you have a DPF on your car, then I wouldn't add that 2-stroke oil to the fuel.

The oil in your link is JASO FB, which has an ash content of 0.25%.
Working on roughly 20000 km per year, you'll be filling the car up 26 -27 times, = 5.3 litres of oil burnt / year. With 10.6 gm of ash.

Again, roughly: your engine oil, which should be low ash, has an ash content of about 0.5% (Castrol Edge), and if you burn 1.5 litres of oil per year, gives you ash of 6.4 gm.

So by adding the 2-stroke oil, you're more than doubling the quantity of ash going into the DPF.

hth

 

[Scoob]

That's odd, speaking to people on the other forum, the 2-Stroke I used actually burnt cleaner than the fuel! I think I must have linked to the wrong stuff, one one I bought is about £12 for a 1 litre bottle, not £5.99! However as that would give me 5 200ml shots in a tank (only 52 litres on Focus) I was ok with that.

Sorry, my bad. When I visit the Focus again (it's stored miles away) I will grab the actual bottle from the car.

You are 100% right re: your observations! More ash/soot is bad, especially with a DPF. You'd need to 100% ensure it was super-low ash (lower than the fuel like mine) for a DPF car most certainly. I was less worried on the Focus, not having a DPF and all, but I didn't want to risk any more particulates.

Scoob.

 

[tode]

That's odd, speaking to people on the other forum, the 2-Stroke I used actually burnt cleaner than the fuel! I think I must have linked to the wrong stuff, one one I bought is about £12 for a 1 litre bottle, not £5.99! However as that would give me 5 200ml shots in a tank (only 52 litres on Focus) I was ok with that.

Sorry, my bad. When I visit the Focus again (it's stored miles away) I will grab the actual bottle from the car.

You are 100% right re: your observations! More ash/soot is bad, especially with a DPF. You'd need to 100% ensure it was super-low ash (lower than the fuel like mine) for a DPF car most certainly. I was less worried on the Focus, not having a DPF and all, but I didn't want to risk any more particulates.

Scoob.

I think you may have been misinformed somewhere: there's no way that commercial diesl could have an ash content greater than 0.25 % (you would be sending 3.5 kg of ash to your filter every year).

I don't know about the UK, but in France the commercially-sold diesel fuel must have an ash content of less than 0.01%.

 

[spock500]

There's a fairly detailed article about Mercedes racing adding two stroke to some of their endurance cars on rallies. I always thought they shipped in their own juice but I guess not, leaving them to the variables of local stuff.

ATF is the other additive which has produced good results although from memory this is the non-syth stuff.

Steer clear of veg oil in post 2000 vehicles as these are a different ball game altogether, big bills will ensue otherwise.

 

[Scoob]

I think you may have been misinformed somewhere: there's no way that commercial diesl could have an ash content greater than 0.25 % (you would be sending 3.5 kg of ash to your filter every year).

I don't know about the UK, but in France the commercially-sold diesel fuel must have an ash content of less than 0.01%.

Sorry, I wasn't clear. The stuff I linked to was wrong, that's not the stuff I was using, the price is way too low. I specifically chose some very low-ash stuff, but I cannot remember the details. I bought it many months ago, as I stopped driving for a while due to a back injury.

Supposedly the stuff I use burnt cleaner than the actual diesel fuel - that's how it helped reduce emissions, otherwise it would add to them on a MOT smoke test I would have thought. Still, all the research I did was specifically for my Ford and other cars without a DPF. Largely the reason for this post, so the warning about high-ash 2-stroke oil (relative to the diesel fuel) is very important.

Scoob.

 

[Triv]

Here it is!
It's a lot of reading.

http://www.freel2.com/forum/topic878.html

 

[Scoob]

Here it is!
It's a lot of reading.

http://www.freel2.com/forum/topic878.html

Nice, thanks. That in essence is what I've read in the past, and where the discussion led on the other forum. However, the tricky part was nailing down an exact product for people to use.

The post does suggest that using proper low-ash 2-Stroke oil is even more beneficial to those running DPF's - so the concern was unfounded. I admit, I wasn't entirely sure back then exactly what a DPF did. I know my friends newer Ford needed a regular top up of some fluid that cleaned the DPF. If it runs out - this is NOT a service item! - the car goes into limp mode! Bad.

Correct me if I'm wrong, but doesn't the DPF basically trap the particulates like any other filter during normal driving? Equally, people talk about them "regenerating" on long or more spirited drives, isn't this just the collected soot being blasted out the back again? If not, where does it go? DPF's seem a little pointless to me, and, like many other parts, seem to have been designed to pass a given test rather than do anything useful. Consider how many problems are caused by DPF's and EGR's when they inevitably go wrong...

Cheers,

Scoob.

 

[mej]

DPF's seem a little pointless to me, and, like many other parts, seem to have been designed to pass a given test rather than do anything useful. Consider how many problems are caused by DPF's and EGR's when they inevitably go wrong...

Hear hear................