Oil too full?

[billbill1]

I'm no expert and don't claim to be, I think it has more to do with the positive crankcase ventilation than anything. If there is oil above the return tube to the sump, then the pressure would build through the engine and that could blow the seals. There has to be some room for expansion and contraction under normal conditions, you won't blow up an engine by running a quart or two low either, as long as there is enough oil for the pump to pick up and flow through the bearings and above the intake to the pump in the sump.

 

[KICK]

most diesel engines ( at least the ones I've worked on) have the oil returning to the crankcase via gravity from whereever they spilled out, there isn't a dedicated oil return to the sump in the strict sense.

crankcase pressure is caused by a couple items, namely blowby and the pistons moving causes a displacement of the air in the crankcase.

 

[fattyfat1]

i also have a 2305. engine oil is fine but i had questions w/hydraulic fluid levels. on my 4310, fluid was always in the sightglass running or not. on my 2305, when my loader is on, level is fine when cold, and the manual says check when cold. when i removed the loader to mow my lawn, i saw no fluid in the glass. chalked this up to loader holding fluid. went to see dealer. he handed me 1qt. free. added quart and w/ loader off i deduced i was 1 qt. low.started tractor, fluid completely dissapeared out of glass! back to dealer-this time to talk to mech. he handed me another qt. of hyd. fl. and said "YOU CANNOT OVERFILL 2305 BECAUSE IT HAS A BLOWOFF. IF THE FLUID EXPANDS OR YOU ADD TO MUCH IT WILL END UP ON THE GROUND. YOU WANT TO SEE FLUID IN THE BOTTOM OF THE GLASS WHEN RUNNING WHICH PUTS IT WAY ABOVE THE GLASS WHEN COLD." i came to the conclusion that my 2305 was delivered a little bit low on fluid, hence the two free qts. i walked away with. hope this helps.

 

[Deerfoot]

fattyfat1, thanks for your hydraulic review. I have never seen my site glass below half. I know that while the tractor is cold sitting level in my garage the site glass is all red. I can't tell you the exact conditions in the field I've seen it at half but I will watch it more closely. I also haven't had the loader off much so I will see if there is a difference with that set up as well. I was wondering if your mower had a hydraulic or manual lift and this was another thing to consider in the scenario. The fact that both of us have had "fluid issues" drives home the point that everyone needs to check their levels, even on a new machine.

 

[fattyfat1]

very true! my mower lifts off of a linkage connected to the three point, so that would be hydraulic. try starting your machine and look at the sight glass to see if it drains, i find this strange because my large tractor always has same amount, running or not. 4310= 7+gallons of fluid. 2305= 3.4 gallons of fluid. i'm interested too see if yours does the same thing. just make sure when it's running there is fluid visible in the bottom of the glass, the mechanic seemed adament about that.

 

[tallyho8]

I'm of the opinion that the level of the fluid doesn't really matter until the crankshaft starts whipping the oil into foam and you begin losing oil pressure due to aeration of the lube oil , OR the oil level is so low that you start sucking air along with the oil which also causes low oil pressure for the same reason.

Though I am not an expert, I am of the opinion that your cylinders are lubricated bythe splash system, not by oil pressure, and if your oil is too low for the crankshaft to adequately splash oil into the cylinders, it will cause excessive ring wear and cylinder wear leading to low compression and smoking. When you are a quart and a half low on oil in a normal five quart engine, the cylinders will not get oiled properly even though you still have normal oil pressure.

 

[Soundguy]

That sounds about right.. they have left space int he hyd sump for extra oil.

On my large tractor, it holds 42 quarts or so oil.. and can be safely 'overfilled' by another 19 quarts... to allow for hyd implements / remote usage.. etc... etc..

Soundguy

i also have a 2305. engine oil is fine but i had questions w/hydraulic fluid levels. on my 4310, fluid was always in the sightglass running or not. on my 2305, when my loader is on, level is fine when cold, and the manual says check when cold. when i removed the loader to mow my lawn, i saw no fluid in the glass. chalked this up to loader holding fluid. went to see dealer. he handed me 1qt. free. added quart and w/ loader off i deduced i was 1 qt. low.started tractor, fluid completely dissapeared out of glass! back to dealer-this time to talk to mech. he handed me another qt. of hyd. fl. and said "YOU CANNOT OVERFILL 2305 BECAUSE IT HAS A BLOWOFF. IF THE FLUID EXPANDS OR YOU ADD TO MUCH IT WILL END UP ON THE GROUND. YOU WANT TO SEE FLUID IN THE BOTTOM OF THE GLASS WHEN RUNNING WHICH PUTS IT WAY ABOVE THE GLASS WHEN COLD." i came to the conclusion that my 2305 was delivered a little bit low on fluid, hence the two free qts. i walked away with. hope this helps.

 

[Dusty]

If the engine oil level is above the "full" mark, the crankshaft can whip the top surface of the oil into a foam, but it will no effect the oil screen pick up, until all the oil became aerated, which will be hard to do. The one thing that over filling does is to put too much oil on the piston skirts and that will challenge the oil control ring to keep the excess oil wiped and away from the compression rings. It will not harm the oil rings in any way, except to possibly gum them up if the oil is old and depleted of its detergent qualities. Over filling will not effect the seals, since the crankcase seal is never under pressure. The oil pump lubricated the crankcase bearings, camshaft bearing, connecting rods, lifters and associated parts of the valve train. All the external seals to a engine are to keep the oil in and are not lubricated. If you have a worn ring problem, and the combustion gasses are pressurizing the crankcase, then that can lead to seal failure as a result of the excessive crankcase pressure. In the old days, engines had road draft tubes that carried the excess pressure away from the engine interior. Then in 1962, the "positive crankcase ventilation system" was implemented with the use of a PVC valve to burn these gasses, rather than vent them to the atmosphere. This was the single most important step to eliminate engine pollution of the atmosphere. If you are finding oil in the air cleaner of the engine, then that indicated that the rings are worn and compression is getting past those worn rings and pressurizing the crankcase. In turn, that pressurized air containing oil is going through the PVC valve into the air cleaner to be burned. The cooler air in the air cleaner is condensing the oil that is in a gaseous form back into oil droplets and depositing them at the base of the air cleaner. All this applies to gasoline engines. Don't know exactly how it is handled with the diesel engine.
Dusty

 

[KICK]

Though I am not an expert, I am of the opinion that your cylinders are lubricated bythe splash system, .

maybe on an ancient engine or a Briggs.

they dont want the crank dipping in the oil, it causes aeration and low oil pressure .

some engine have the underside of the pistons cooled by lube oil, whether thru a drilling in the con rod or a nozzle from the oil rifle.

most of the oil lubing the cylinders is flung intothe cylinders from the oil that bleeding past the bearings in the crank.

 

[KICK]

. Don't know exactly how it is handled with the diesel engine.
Dusty

most heavy duty diesels are still venting the crankcase to the atmosphere.

light duty engs... it can vary, might be to the intake or turbo inlet or overboard depending on emissions requirement for that vehicle or machine.