Interesting info on 2cycle diesel lubrication

[Iceni John]

Anyway, back to the OP's Shell article  -  what's interesting is that it says the large marine two-stroke engines don't have sumps, and instead their oil is injected, used, then drains away, in other words they're considered to be Total Loss Lubrication.   (Sort of like old British cars and motorbikes, where the oil gets totally lost after a while as it drips out everywhere.)   Shell's description sounds very different from the Detroits we know and love.   No sump?   This has piqued my curiosity  -  I'll have to read up about the huge marine two-strokes.

I was reading something else recently about Gardner two-stroke diesels  -  no, I didn't know that Gardner ever made two-strokes, but apparently they did, and they were reversible!   I wonder how that would have worked, especially regarding their lubrication.   Maybe their oil pumps worked both ways?   I know that a Detroit running backwards won't last long because of lack of oil.

Just curious.
John 

[luvrbus]

The Copper V-250 was a 2 stroke the direction you started the engine was the direction it turned fwiw still a lot of those in use on compressor stations

[fortyniner]

Some oils were near 1.5% which is only 0.65% more than Delo 100 at 0.85%.  Doesnt seem like much but Delo 400 specifically warns its not for 2strokes. So roughly 0.5% apparently is a significant difference. The way I see it if 0.5% is significant then 0.1%  difference is not trivial.

This stuff lists for $71 5gl:
http://www.warrenoil.com/MSDS-Spec/PDS/Coastal/PDS%20-%20Coastal%20HD%20Fleet%20Engine%20Oil%2010%2030%2040%2050.pdf

I think Autozone here in Texas can get it.

[belfert]

I suspect the reason Delo 400 is not recommended is because Detroit calls for 1% or less ash and Delo 400 is way over that.  I agree with Clifford that bus nuts tend to spend way too much time agonizing over which oil to use in their bus.  I don't have a two stroke, but if I did I would just use whatever oil met the Detroit specs.  I know a number of bus nuts who use a local bus garage for oil changes (myself included) and I doubt they question the specs of the bulk 40 weight oil used for two strokes.

[luvrbus]

Go to a store where they sell Delo 400 in 15/40 and the straight 40 read carefully both cans it will say on the straight 40 w meets specs for MTU 1 and 2 engines now read the 15/40 can and it will say on the can for only one engine (4 stroke) it's been that way since 2010 believe the internet or your lying eyes lol

good luck

[bevans6]

There are other reasons beyond ash content that makes an oil suitable or not for two stroke Detroit's. 

Brian

[luvrbus]

Brian, the ash in oil has always had to been adjusted for the sulfur content in fuel  on 2 strokes these guys carry on about oil but when it comes to fuel what ever a station sales, number 2 diesel has never been the primary fuel for the 149 series engine fwiw

[RickB]

Tom P aka Forty Niner,

I apologize if I did anything to skew this post away from your original question. That said, I think whoever posted that we may have to look at ordering our oil from a wholesaler in the near future may be closest to answering your post correctly. It is getting harder to find all of the oils that have been discussed in large enough quantities to keep us from getting worried about running out. I have always been able to order through NAPA basically any one of a half dozen compatible motor oils so I'd check there first.

We're not "running out of oil" for our buses that's for sure. They're just not stocking it on the shelves is all.

I think the reason it is such a sticking point for the board has more to do with the fear of getting the wrong oil and needing to do a rebuild than just trying to be proactive in protecting our engines. Let's face it, we all have a pretty good idea that any day you have to replace an engine in one of these behemoths is a pretty bad day! Unless it's the day after you win the lottery or a rich friend dies and leaves you all their money. In that case, I'll take a Cummins ISM tuned to 450 HP and a B500 to go... Do you guys deliver?

All in fun,
Rick

[TomC]

Just for fun information:

On super large 2 stroke engines used on ships-the kind that are directly coupled to the propeller with no gears and are directly reversible (we're talking 38"x98" bore and stroke compared to a 71's 4.25"x5")-yes they do not have a sump in the engine-but the oil is drained back to big tanks-usually around 1,000gals.  Then the oil is fed through a centrifuge, water/oil separator, and filtered multiple times before returning to the oil pump.

The biggest 4 stroke engines are about 40,000hp-because of the massive reciprocating masses, the 4 strokes just can't get larger.  Then 2 strokes take over.  The largest is a 14 cylinder engine pushing around 130,000hp at 102rpm (your engine cranks over faster than that).  Goggle worlds largest diesel.  Good Luck, TomC

[RickB]

Tom, the question is what viscosity and ash content is that 1000 gallons of oil??? Just kidding, under no circumstances do we need that question answered.

RB

[RickB]

There's a place to consider getting WMO for our more adventurous thrill seekers. What an expensive oil change. Holy crap!

[GilligCrown]

I don't mean to be the "math police", but 1.5% content is 76% higher than .85%.  That DOES appear significant. That said, I currently use Shell 40W with 1% content in my 6-71; I believe this is barely within spec.

[fortyniner]

Right, 76% higher, I should have said 0.65 difference in percents. The point I was considering was whether the change between 0.85 and ~1.5 is really enough to cause trouble down the road. Is there an ash tipping point, go over the magic 1% and boom, good by motor? I sort of doubt that but Im new to these beasts and would rather be taught than learn (the hard way).

-Tom P.

[GilligCrown]

Consider what would happen if there were 76% less air

[chev49]

i kinda doubt it also... not to mention occasional white house math....