Slobbery exhaust - new engine

[veggie]

You misread my post. Both sumps are at the same level which is 5/8" up the dipper and slightly above the "valley" where the upper sump meets the lower.

Thanks, Geno

Ahhhhh! got it. Sorry about that.

veggie

[Ronmar]

Hi Geno,

Actually, I think that if your oil pump were to stop working, your upper tray would be drained within 1 minute because the dip tube would splash the remaining oil into the lower sump with no new oil to replace it from the pump.
After that, you start to hear funny screeching noises and notice smoke coming out of your crankcase breather.
Then the dreaded knock, knock, knock of a burned out bottom end bearing.

veggie

I think it would take a lot longer than a minute.  I shot some video thru my open breather case cover during startup and running.  Most of the oil moved by the dipper is to the sides and rear of the case.  these portions of the case drain back into the upper sump.  I also shot some with a plexiglass window in place, but those are not so good, as the window quickly becomes covered and you can't see thru it.  What I found was that the oil covering the window was that thrown off by the crank, which was the oil pumped there by the oil pump delivery tubes...  Geno's filling of the lower sump till it just spills over into the upper sump negates this problem partially.  A good portion of the oil pumped lands on the crank drive gear that in turn spreads oil back thru the cam gear.  The roller bearings also need oil, but very little.  Is splash enough to meet these needs by itself?  Well most old briggs and strattons don't have oil pumps, and they run for a good long time with only splash and very similar internal mechanisms...

here is one of the vids.

[veggie]

Question:
Just wondering.....
After watching that excellent video, I could not see a dipper making any splash on the surface of the oil in the pan.
If there is no splashing from a dipper tube, how are your big end bearing and cylinder being lubricated?
Does your engine rely on the excess oil from the bearing delivery tubes to be thrown up by the crank weights?

veggie

[vdubnut62]

It's definitely there Veggie, if you look very closely, you can see a "wake" that disappears VERY quickly.
Evidently the engine was up to operating temp at the time the video was shot, and the oil was thin as a result.
Ron.

[Ronmar]

It's definitely there Veggie, if you look very closely, you can see a "wake" that disappears VERY quickly.
Evidently the engine was up to operating temp at the time the video was shot, and the oil was thin as a result.
Ron.

The wake is there Veggie, but the frame rate of my still camera shooting video is not very good, so it has a little bit of strobe/stop action effect to it.  This actually worked out pretty good to capture that wake, as the frame rate and the wake depression from the dipper passing come into coincidence about 10 seconds from the end of the 1 minute video.  If you look closely on the back wall when the crank swings up, you will see a thick trail of oil up the back case behind the dipper.  The wake of the dipper also slings a little onto the end of the crank arm I think.  At any rate, as the crank swings around, the oil that the dipper and crank collect is slung up the back side of the case and bounces around inside the case.  Some of this oil makes it to the cylinder sleeve and up into the piston, and some is bounced onto the rod.  This oil then runs down the rod and onto the upper half of the bigend and into the lube oil holes.  That is why cleaning the sand out of the inside of the piston is so important, as this splashed oil will carry it down the rod and into the big end bearing.  The pumped oil is mostly delivered to the crank  gear and TRB's. The right hand oil feed pipe in the video has 2 holes.  One points at the TRB and the other at the crank. The oil pump operates in opposition to the injector pump, so it is squirting it's oil as the crank passes thru the top of the exhaust stroke.  I don't know how much of that oil hits the crank arm as it passes.  I think most of the oil from that hole goes right in the upper sump as the pump is done pumping before the crank reaches that point.  You can see it in the video about 20 seconds in.  oil starts landing beside the puddle on the right front side.  I think most of that pumped oil slung by the crank is delivered outside the cylinder liner circumference.
  The original listers didn't use TRB's, they used traditional bearings, and the pumped oil was fed to the top of these bushings.  I would guess even less oil made it onto the crank arms in the original listers. 
 
Vdubnut62, The oil in this startup and run video was cold(maybe 65F).  Note the clean white case surrounding the oil.  It had set for a few days before I shot this.  As I did this to illustrate a point in another discussion, one of the things I was trying to capture was how long it took the oil pump to start delivering oil, which was about 18 pump strokes from a cold start.  You can see the right hand oil delivery pipe start to spurt oil just as the crank gets up to speed.

[NoSpark]

Like Geno I fill my sump and tray completely full until its more than half way up the dipper, between 4 to 5 quarts of oil. Its never slobbered or used oil, not enough to notice anyway. Mine also came with an oil pump and filter. About a year ago I pulled the crankcase cover off while the engine was running so slow it was almost stalling on compression stroke, needless to say I don't run it that slow anymore, no splash lube at all at that speed .

[vdubnut62]

Ronmar, that really surprises me. I would have thunk that the cold oil would have held the wake made by the dipper/slinger far longer.
I guess I should not make assumptions based on conjecture. Sorry "bout that.
On another note, have you considered one of the hollow dippers and a set of the bearings with the plain top shell? They look like they would be the cats whiskers to me. I think John F has info on his website.
Ron

[Ronmar]

That cold oil wouldn't hold the wake very well IMO.  When warm, I bet the wake travels off to the sides more.  I think it would kind of be like sand when cold, and except for near the point of impact, the rest of the oil just absorbs the motion instead of transmitting it. 

It would be cool to get inside with a slo-mo camera and watch the dipper wake.  It leaves quite a depression as seen in the video I posted, so that oil is going somewhere.  IMO, it is thrown nearly vertical like a large ships bow wave.  I think the top of this wave is thrown against the rod and crank arm where it meets the rod journal. I think the oil thrown up at this point on the crank is the most important as it is this oil that is then slung up the rod and into the piston and cylinder liner when the crank swings past TDC.  This is the oil that lubes the rings and piston wrist pin...

The hollow dipper looks interesting as does the slinger cup delivery device that XYZER came up with.  If I recall, it put so much oil in the rod bearing area, and so much was slung up towards the piston, that he couldn't stop it from slobbering:)  I am sure that one could be refined some.  That one IMO has the most merrit as it provides a steady supply of oil to the rod bearing.  Probably almost as good as pressure lube would.

Unfortunatly the hollow dipper is only in limited use on these engines.  The idea has merrit, and will probably work fine.  But I think I will defer to the folks in Dursley and at B&S.  They had the same technology to develop the hollow dipper and they didn't.  Either they just didn't think of it, or they didn't feel it was necessary.  Time has proven these decisions to have been correct, or at least appropriate as both these engines run a good long time under sometimes extremely adverse conditions.  The pumped oil in the original CS's only went to the top of the crank bushings and I doubt much of this oil got slung anywhere, except perhaps along the cam drive gears.  Everything else inside was splash lubed.

The original parts diagrams I have seen show the CS dipper to be a thin round rod, pretty much the same relative size as that found on my clone...  In fact, the original diagrams show a splash plate being used over the upper sump.  This plate, wth a slot in it that the dipper passes down thru during it's arc thru the oil, limites the ammount of wake splash that could hit the bottom of the crank...

These designs last a good long time, so either someone was very lucky, or they had a very through understanding of what was going on inside the case...   


   

[mike90045]

What gets oil to the upper rod /piston wrist pin ?  Just random mist & splash?

[Ronmar]

I think the dipper wake thru the oil transfers some to the crank arms on either side of the conrod.  This oil is then slung back off the crank radially as the crank rotates, up the back side of the case and up into the cylinder and into the piston.  There is an oil hole on top of the rod little end that admits oil to the rod small end bushing.  If you watch the video, look behind the crank at the back wall.  You will see a single trace of oil appear at first on the back wall behind the dipper.  Then that oil gets wider as the ammount of oil thrown builds up.

[mobile_bob]

its no secret i am a huge proponent of the hollow dipper and plain upper brg
reasons being:

1. there is ample evidence from those with high hours having issues with brg failures, signs of delamination
and other stess issues in the high pressure zone of the big end brg upper shell.

2. those engines that replaced the oem style shells with plain upper shells have dramatically increased their
lifespan

3. we have no idea what the original lister metallurgy for the shells they used was, further we can assume there
is likely some changes to the fuel that is burned in diesel engine's which might increase cylinder pressure or hasten
the burn rate, or both.

4. we don't know the metallurgy of the indian brg shells? but we can assume they are likely alloyed to work with
pressurized modern engine's.  the old style splash lube likely had a completely different alloy, allowing far less oil to
keep the things working as designed.

i don't have any answers to any of these questions, and i would strongly suspect anyone that does have these answers.

so failing that, it would seem prudent to me that anyone anticipating very long hours, under heavy loads, burning alternate
fuels that might have a faster burn rate,  might well be served to get rid of the oem grooved and drilled upper shells, in favor
of the plain brgs and hollow dipper.

also the odds are dramatically lower getting sand up the dipper tube than that which dislodges from the underside of the piston
and is carried down by the oil splash into the catch funnel that is at the top of both oil feed holes in the top half of the conrod.

maybe you don't need the plain shells, but if you see signs of stress, delaminations, wear, or other issues in your grooved shells
long before you think you should be seeing it, you might look into upgrading to the plain shells and hollow dippers

bob g

[cgwymp]

3. we have no idea what the original lister metallurgy for the shells they used was, further we can assume there
is likely some changes to the fuel that is burned in diesel engine's which might increase cylinder pressure or hasten
the burn rate, or both.

4. we don't know the metallurgy of the indian brg shells? but we can assume they are likely alloyed to work with
pressurized modern engine's.  the old style splash lube likely had a completely different alloy, allowing far less oil to
keep the things working as designed.

I happen to have an OE (appears to be current production, not NOS) Lister-Petter big-end bearing set.  It's of course drilled & grooved in the top shell.  Wonder how that fits into the equation?

[mobile_bob]

i would be much more comfortable and would not argue in favor of change, "if" one is using
OEM lister brgs, because my bet is they are in keeping with the original engineering specs for the engine.

the indians on the other hand get their brgs made by some bigger brg manufacturing company who's predominate
work is for 1st world modern engines using full flow filtration and a real oil pump.

there are so many brg spec's that fit the same engine but for different duty it isn't even funny

for instance, GM once used (and may still use) moraine brgs they had a relatively soft white metal alloy
that had a specific characteristic for not sticking to the crank on many cold starts for a car.

clevite made there famous "77" series that were alloyed to be much harder, for higher output engine's
as well as "112" and "122" brgs which were even harder and would put up with more abuse, but
are harder on the crankshaft (wear because they lack the soft metal that the grit gets lodged in)

all i know is i have seen with my own two eyes listeroid groove and hole brgs beginning to fracture/pit/flake
in engines with maybe a couple thousand hours, and it could be blamed on numerous issues such as fast timing,
faster burning fuels, heavy loading etc. but
after these engine's were changed to the plain upper shells the same time period has come and gone several times
over and no such sign of stress has become evident.

one particular user which will remain unnamed reported that after iirc 600hrs he checked his shells and took pic's
they looked like brand new brgs with no signs of anything on them.  now 600hrs isn't much, but not many engines
run even 600hrs without some signs of scuffing, scratching or wear.

bottom line, run the grooves and hole type brg if they are oem lister, no problem with me at all

if however you can't get any other than indian listeroid brgs, and have a choice, buy the plain brgs
fit them with a hollow dipper and rest assured that this issue is solved, if you plan on long hours and all sorts
of loading, fuels etc. or

stay with the listeroid grooved and hole brgs if you only need the engine for backup duty, where it likely isn't going to
run enough over the year to justify the added expense and labor to install.

bob g