Adding oil to diesel fuel?

[newhaul]

Originally Posted by Lippe

) for an older product the case is not necessarily same with a modern dielsel engines.

exactly the issue for me on my old truck stanadyne would not honor its warranty on my new rotary injection pump with the use of ulsd unless I used a lubricity additive . They of course recommended the one they produce but 2 cycle was approved by them for the warranty . ( had the letter from them on file back then to )

[Lippe]

Originally Posted by hellosailor

Diesel is among the things that are often called "fuel oil" so the idea of, well, adding more or other oil to THE fuel OIL isn't so crazy. I'd normally join the camp that says follow the factory manual, there's usually a reason for whatever they say. But, that reason may be something like "adding oil is going to change the emissions, we can't have that" so the factory may be saying not to add oil for political/environmental reasons, not strictly performance issues.

But I'd tend to expect that following the manual will be "good enough" whatever their reason for doing it that way.

It is question about sensititive technology instead of playing with words. My point is that we shall not give technical advice to people who trust this site without technical understaning and take seriously comments that may have expensive or dangerous consequences.

[a64pilot]

Originally Posted by Dsanduril

Don't disagree with you there, but 95% of the alternatives in the study you linked get you no better lubricity that what you can get at the pump. So you have to decide which you care more about.



Curious if we worked on opposite sides of the same study as I worked for a bio-fuel manufacturer that got a 10% mix of their fuel certified a couple of years ago. Ended up with a two-year trial on Cathay Pacific on flights from France to Hong Kong and certification for all flights in Brazil (American bio-fuels company, Brazilian production facility). Trial ended last year, but I've been at sea so haven't really kept touch.

I believe the first nine products increased lubricity, but it was interesting to see that some actually made it worse.

We were trying to Certify a crop duster powered with either the GE H80 engine or one of several P&W engines to burn the Brazilian Bio Diesel.
It was apparently tax free in Brazil and for whatever reason great emphasis was placed on it by marketing.
My feeling was it was a waste of time as we had years ago Certified Diesel and no smart operator was using it as the increased maintenance and parts way exceeded any savings of the cost of the fuel, and that Bio would certainly be the same.

But we got most of the way through the hurdles, and then something changed Brazil started taxing it or something, and suddenly marketing didn’t care anymore.

In truth it really was from the beginning a waste of time, because they were burning it anyway, and could care less if it were Certified or not.

Marketing was very, very good at wasting Engineering time, and they had the ear of the owner, so a lot of time was wasted

[Delfin]

Originally Posted by Dsanduril

Don't disagree with you there, but 95% of the alternatives in the study you linked get you no better lubricity that what you can get at the pump. So you have to decide which you care more about.

Curious if we worked on opposite sides of the same study as I worked for a bio-fuel manufacturer that got a 10% mix of their fuel certified a couple of years ago. Ended up with a two-year trial on Cathay Pacific on flights from France to Hong Kong and certification for all flights in Brazil (American bio-fuels company, Brazilian production facility). Trial ended last year, but I've been at sea so haven't really kept touch.

Read the test results I posted above. Wear can be reduced by 40% or so quite inexpensively.

[Delfin]

Originally Posted by a64pilot

Yes, it comes from the concern of ULSD being a “dry” fuel and having poor lubricity, that is a word by the way

It’s also aggravated by common rails extremely high pressures and susceptibility to wear.

There are much better additives than two stroke oil.

In my opinion the concern of ULSD’s poor lubricity is well founded.
This isn’t a new test, but it was very professionally done in my opinion.
http://www.jatonkam35s.com/DeuceTech...itive_test.pdf

Yes, that study is touted by OptiLube, for obvious reasons. Wear can be reduced, bit some products after completely worthless, including some recommended by many. Biodiesel comes out on top, but carries other baggage of like to avoid.

[TideTime]

Several years ago, I had an certified Yanmar diesel mechanic recommend the addition of a small amount of Mystery Oil to my thirty year old Yanmar 1GM10. However, I doubt if that would be recommended for a new diesel and certainly not if owner's manual advised against it!

[seabreez]

Originally Posted by O_salt

A friend of mine has bought a new Volvo diesel engine and the salesman / Installer is telling him to add 1% 2-stroke motor oil to his diesel fuel to help lubricate the engine.

Has anybody else ever heard of this?

In older diesels, in Cats and GM Rosa pumps, I personally had heard this adding of transmission oil in the fuel tanks. Yes, I did try it and still do today. We added the oil for lubricity of seals in the injection pumps to lubricate seal to prevent them from leaking. This solution had also helped for better idling, and we attributed this to lubricating the injectors.

[newhaul]

Originally Posted by seabreez

In older diesels, in Cats and GM Rosa pumps, I personally had heard this adding of transmission oil in the fuel tanks. Yes, I did try it and still do today. We added the oil for lubricity of seals in the injection pumps to lubricate seal to prevent them from leaking. This solution had also helped for better idling, and we attributed this to lubricating the injectors.

the Mercon dextron series of transmission fluid is a great injector cleaner for those of us that still have the good old mechanical systems( don't know about electronic injectors )
it will also clean out all of the soft carbon deposits in the engine . It is after all a petroleum based soap. Keeps my old md2 singing like a sewing machine.

[TheThunderbird]

Volvo TAMD 31LA 1998

I was recommended to add MINERAL OIL. 1liter for a 500liter tank.
A 2nd mechanic detected it, and approved it.

[MarkSF]

Originally Posted by Dsanduril

The manual further specifies that fuel lubricity match a maximum wear scar of 520 micrometers - which is coincidentally the same value used in the definitions for ULSD.

When VW's high pressure pumps were failing all over the place, it turned out that a surprisingly small amount of gasoline in diesel will reduce the lubricity below the acceptable level, like 1-2%.



Be careful where you buy your diesel. I've bought diesel that actually smelled like gasoline, there was that much gas in it. Didn't go back to that station again.

[petermjdavies]

Unlikely. Read the manual.

[DHHerndon]

A much better alternative would be to add Biodiesel. You can normally add up to 20% biodiesel to regular diesel. Biodiesel has very high lubricity and makes the engine run smoother. You can normally purchase 20% biodiesel (B20) and use as is, or purchase 100% biodiesel (B100) and mix your own. I have been using B20 for around 15 years for my old Yanmar 2QM20 diesel. Once when the seal broke between the fuel pump and the crankcase the crankcase filled up with biodiesel. This kept the engine from burning up and saved purchasing a new engine. All I had to do was to replace the fuel pump and seal.

[tortola7]

Not a Diesel engine, but my lawnmower mechanic says to add Opti2, which is a 2 cycle oil to my 4 stoke equipment. Been doing it now for about 6 years with no issues. Best part is I have 1 fuel for all my lawn equipment....obviously lower cost items than a new Volvo engine.

[GrowleyMonster]

Modern small diesels don't need this. You will not notice the difference in engine wear. It won't hurt the engine, but you will probably be in violation for doing it. On a vintage diesel there is a pretty strong case for this though, IMHO. Just remember, you are not hearing this from an authorized service rep or a lawyer so YMMV.



I am on a ship right now, but as the Bosun, not an engineer. I can ask, though, if it is common practice at sea to add used LO to the HFO. I am pretty certain that when we have to run diesel, though, that it would be illegal. In areas where there are no restrictions, HFO (Heavy Fuel Oil) is burned because it has more BTU per pound than diesel. These are low speed diesels, usually turning at around 90 RPM. Talking about engines the size of a small 4 story building, with piston heads big enough to dance on and crankcases you can physically enter and stand up in. I know I have in the past been advised by the engine gang to dispose of used oil, hydraulic oil, solvents, even paint, into the bunkers. Particularly on steam ships, of which few remain these days. I will ask if we can and do still burn used LO with the HFO or not but it definitely can't go in with the diesel. Won't hurt the engine but it is most surely illegal.

[Bentwings]

I have a ‘99 Dodge diesel with well over 400k miles on it. No additives since about 150k. No motor or injector issues.
In the early days of low sulfur fuel Walmart 2 stroke oil as an additive was common. Diesel Service White was also used for many years. Then with to advent of 2-5% biodiesel additives were not needed as 2% biodiesel is the best you can do. No additives are better. We have 5% here year around and it works very well. Any common rail diesel of the modern era does not need additives. It’s old school. Modern diesels after 2007 also must use DEF on a separate tank. I’m not really up to date on boat diesels but unless it has a DEF tank no additives are needed or advised. Many mfg will void warranties if non recommended additives are used. To be safe I’d surely look at the owners manual or call the mfg. don’t depend on “old” mech. Many have not changed with the times.