No worries rollguy i was asking some questions here http://www.peachparts.com/shopforum/diesel-discussion/341176-well-my-c-used-work-91-300d.html and your name came up. I have a 91 with a denso 10pa15c though.

Answer
 

I run hydraulic oil as often as I can get it, in all of my turbo or naturally aspirated diesels summer and winter.

Generally I can run 100% light/medium hydraulic oil down to -0°/-20° F, and thin it with kerosene for lower temperature operation.
Heavy hydraulic oil may need to be thinned at +40° F and lower.

There are NO concerns about lubricity.
Few hydraulic oils have a cetane number below 50.
Many common hydraulic oils are close to diesel viscosity.


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My first test was with 2/3 waste motor oil (2 units of diesel and 1 of oil).
After a testing ride i can say that i have noticed that engine has less power.
I have got oil from mechanic office, and i can be sure that there is not more than 10% of gasoline in it, although it was insured me that. Because they use gasoline for cleaning.

After 10 km of testing i have opened gasolin filter which i had added and i have find many small particles in it.


So, i will look to find best resolution for filtering off board and on car also. I have add gasoline filter. But i will add another diesel filter before gasoline, because it is rougher than gasoline. And then to find filter which can be cleaned or sort of filter with housing and exchangeable part. Maybe i could use an oil filter and housing for this porpouse from an W124.

I will look for WVO and hydraulic to make comparison.

Exhaust gases are not darker as before.

It is imperative that you filter the oil before you put it in your tank. The loss of power was likely caused by clogged fuel filters.

The process I use is like this: cut oil with 15-20% RUG, let oil mix settle for a few days, filter through a 10 micron sock filter followed by a 1 micron sock filter, put oil into fuel tank.

Error
 

The correct answer:
* Filter the fluid 50 micron
* Dewater (remove water molecules from) the fluid
* Settle the fluid
* Filter the fluid 10 micron

Adding more vehicle filters = more sludge / sediment failure points.

Replacing the Mercedes factory filters with a good used Scania or other LARGE equipment / machine filter unit could be an option for you.


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Prefiltering is life or death when running waste products. Diesel equipment fiters are nice because of their large capacity and dont clog quickly. I like racor as they have a clear base and multiple micron rating options.

Yah, but don't do this.

It took less than 2 drums (55 gal) clean fresh new hydraulic oil to cake new set of glow plugs with glossy hard sugar coating like carbon causing 4 out of 6 burning out prematurely. Car was getting harder and harder to start over a period of about a month, as each Bosch plug began failing in rapid succession. This was about 3 months after getting into the hydraulic oil.

Learned two things:
1. you can start a good compression om603 on 3 good glow plugs, but it just doesn't cut it having only 2 good ones.

2. don't burn hydraulic oil pretending it's similar to WVO.

This is on a 2 tank system that normally burned WVO, for years... with no problem like this ever happening. It has injector line heaters and raises temperature of alternate fuel to a constantly monitored 80*C at the point on the hard lines just prior to the injector nuts. Proper flushing and switchover to diesel on every run. Plugs haven't failed since getting back to WVO.

The plug cost and labour of putting a new set of 6 in did not justify the fuel savings of less than 100 gal.

Do you happen to know any more information about the oil you ran? I'm thinking that maybe it had some additive in it or some sort of synthetic blend? Did you mix it with RUG or anything else?

I started running a blend of WVO and RUG in my 83 300td. I'm curious, since you have so many miles on that sort of fuel, what's the ratio you run at and is the car converted in any way? Thanks a bunch!

No equipment added whatsoever. It gets down to freezing here in the winter, so I run as much as 25% RUG during the winter, and as little as 10% during the summer. During most other times (spring and fall), I run between 15 & 20%.....Rich

It probably did have additives... and they were all fresh. This was new product. I still have the empty drums, I'll have a look for labels and report if I find. Maybe it was synthetic.

Not mixed with anything, straight up in 2nd tank. Mixing with a 2-tank system is counter culture, and is something you do if you're trying to do 1-tank stuff. My suspicion with this oil is that mixing with anything would just prolong the inevitable, stretching time proportionally with the degree of dilution. But that's just an uneducated guess.

Mercedes Benz used to recommend no more than 10-15% dilution of diesel with gas, especially in winter, but there was more sulfur in the diesel then, also.
The key was not to mix premium gas with this because it contained vanadium, so here's one spot where cheaper was better lol. Vanadium apparently wore out FI pump parts.

I found this out reading a whole bunch of old tech literature that came with a bunch of parts. Long story short,I got a 36 x 30 storage unit filled with old Benz books and pre-war/Adenauer/Ponton parts at an auction recently in Roanoke, Virginia. .
Found a couple interesting things, like MB glow plugs wrapped in newspaper dated 1939! Must be for the MB 260D? Still checking.
Another new retirement project, lol.

Hydrex AW68 is Marked on all the drums. Made by PetroCanada, I've attached a spec sheet for it.

Not mixed with anything, just filled the second tank and ran it heated to 80*C like WVO.

Don't do it!

I can't tell if it is synthetic or not but it sounds like there are a lot of additives in it.

I'm not sure what the intended equipment is for this oil, I got it from a farm, and these guys have million dollar combines.. that are very specific about what fluids and oils are allowed to be run in them during warranty period. Typically, only the best, and often involves a company rep inspecting (or overseeing the fluid changes... even engine oil). They're there to protect the brand as much as they are to validate warranty integrity. You know, if company X combine breaks in the field at harvest time that brand is damaged for a large radius of the countryside - regardless of reason. SO whatever additives keep things going smoothly, yup! they're in there.

Anyway, this PARTICULAR OIL is a no-go for veggy burners.

Your mileage may vary with other oils, up to you!