Any idea how much waste motor oil you could add to a tank of diesel without noticeable gray smoke out the exhaust of the 617?

Link to parallel thread.
Filtering used engine oil to use as fuel

For a little over a year, I've burned all the used dino lube oil from my two 300s in the 300TD (the 240 has AmZoil in it). This amounts to about 30+ gallons of used engine oil through the wagon's engine in over 20,000 miles of operation with no apparent ill-effects and (so far) no clogged filters.

FWIW, I do not pay any attention to how much diesel is in the tank, I just dump in the old lube oil and go. I haven't perceived a big change in the amount of smoke produced at speed but there is a very slight increase in smoke generated at idle. I cannot discern a difference in performance either.

The only difference I have been able to detect is the exhaust's smell. It's definitely not that pleasing "bituminous" coal smoke odor but an acrid, burning oil, skunk smell. For that reason, I generally try to burn my waste oil on highway road trips where you aren't likely to be stuck in traffic, smelling like Pepe le Pew.

Right now, I drain my lube oil into a dedicated collection pan that is kept clean and is cleaned out before and after each use. The pan is a potential mess so ultimately, I plan to build a 'topsider' type vacuum fluid collection device and do my oil changes with that. It should streamline things considerably.

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Never a dull moment at Berry Hill Farm.

I used old lube oil for about two months before my IP
failed.
The plungers and barrels wore out due to
particulate, read, "trash", in the old oil. In addition, the
engine ran hotter than normal, and, there was an
appreciable power reduction. As the IP wore out,
starting my 240D got more and more difficult...then impossible!

Did I filter the oil? YES, through shop rags.
What ratio did I mix with good # 2 Diesel? ~ 50:50.

Go Figure!

Ron Rueb

OKC/OK
71 220D 370,000 mi.
79 240D (rebuilt, later donated..son wrecked it)
81 300 SD 288,000 mi.

It's a wonder it lasted that long, filtered through shop rags.

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'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

Even the stuff that made it through the shop rags should have been stopped by the in line and spin-on filters.

__________________
Never a dull moment at Berry Hill Farm.

I agree, if the inline filter and main filter were doing their job, the worst that should happen is you plug those. I don't buy the argument that the used oil killed the pump, at least from the standpoint of particulate matter.

__________________
Keep everything as simple as possible-but no simpler--Albert Einstein

The prefilter is probably about a 20 to 40 micron filter, you can SEE 20 microns! However, it is the 7-10 micron particle size that causes accelerated injector and pump wear. Your stock filter for MB may be a 5 micron nominal filter, but it was not a 5 micron absolute filter and can easily, hour after hour, pass anything up to 10 or 20 micron or larger.

However in the years since it's design, it may have undergone upgrades and may now be 5 micron nominal and 10 micron absulote for instance. Meaning it will stop a precentage of the particiles down at the 10 to 5 microns size, but will pass nothing over 10 microns in size. In other words it will pass particles 1 micron up to 10 micron and nothing larger.

I run a Cat IR-0750, 2 micron absolute on our VW and plan on installing one on the MB in the near future.

Most oil filters run from the 10 micron to 20 micron range, with a few designed for use with synthetic oil that filter down to 3 to 5 micron size.

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

I'm not completely convinced that pump diesel is consistently cleaner than 5-10 microns.

However, in looking for filter specs I came across this:

Chevron Link (BTW this is a good read)

"...While the fuel filters recommended by engine manufacturers have a nominal pore size of 10 microns,1 studies by Southwest Research Institute reveal that the critical particle size for initiating significant abrasive wear in rotary injection fuel pumps and in high-pressure fuel injection systems is 6-7 microns."

__________________
Never a dull moment at Berry Hill Farm.

In all the 10 or so fuel test report's I've seen in the last few years, none have come close to that mark.

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

Sounds like a good reason to retrofit with a 2 micron Racor.

I'd sure like to know for certain the micron rating of the stock spin-on filter.

__________________
Never a dull moment at Berry Hill Farm.

BALDWIN FILTERS

Good informational source

__________________
Never a dull moment at Berry Hill Farm.

I don't know about the old MB filters, but the filter used on the new VW cars with 29,000 PSI pump injection is only a 20 micron nominal. Can you believe that, they are actually using the same filter for the PD engine as was used on the last generation VW 19,000 psi fuel system, which was modified from previous one dating back to early '80's.

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'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

Just called and ask about the micron rating for the Baldwin filter BF1056 listed for our cars and was told 5 micron nominal and 20 micron absolute. In other words it will pass particales as large as 20 microns.

In simple terms it will pass percentage of particles under 20 micron in size down to 5 micron and stop anything 20 micron or larger. Remember most damaging size particles are 7>10 micron in size. So your OEM filter most likely is 5/20 micron and stops about 50% of the particles or less that it needs to stop. With the dirty fuel in this country that is pretty poor.

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

I have worried about the fuel filtration issue on these cars as well. I am not terribly concerned with particulate filtration since there doesn't seem to be a huge problem with IPs and injectors prematurely wearing. A concern I do have, however, is water in the diesel. Does anyone know if our filters have any type of water blocking media?

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Keep everything as simple as possible-but no simpler--Albert Einstein

Not sure of the OEM filter, but the Cat filter is a water stopper, but water has never been much of a problem here in US with the fuel. US standard is max 500 PPM and most fuel reports I've seen have been at 50 > 70 PPM range.

From what I have been told by the testing labs is the big problem is dirty (particles) and low cetane rating. Our cars were designed for fuel probably in the 44 to 48 cetane range (average fuel cetane rating in US in 83 was probably around 48 > 50 cetane) and it's hard to find fuel over 42 cetane in US today. I have seen one report that showed 38 cetane and high particale matter, yet it met standards for preminum diesel in US. Just remember there are 5 standard bench marks for preminum diesel fuel and only 3 have to be met to call the fuel preminum.

__________________
'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.