DP Oil Change every two years

[OneRVer]

Originally Posted by radams

Okay, for arguments sake let's say that the engine manufacturer recommends changing the oil at 10,000 miles. Two owners each travel 5000 miles a year. Owner A drives his unit and never stores it, and owner B stores his for four months per year for the winter. Why is the oil different in the stored unit such that it needs to be changed annually? Won't they both have the same contaminants at the same time? Won't those contaminants be working on both engines whether stored or not? Do the manufacturers change their recommendation if a unit is stored as above? I haven't seen that. BTW what's the rationale for changing the filter annually? Okay, Ready . . Aim . . . Fire . . .

WoW good questions. The stored unit will get condensation which will up the acid count. If the stored unit is being started for a couple of hours each month that should take care of the condensation.

After the filter is used for a year, it does not filter as well as it should, some better than others but the filtering will slow down. Oil stll good, just needs a new filter.

2009_sept_fuel_dilution_diesels[1].pdf This is a good artical for newer diesel engines.

[Elkhartjim]

Originally Posted by OneRVer

WoW good questions. The stored unit will get condensation which will up the acid count. If the stored unit is being started for a couple of hours each month that should take care of the condensation.

My understanding that starting and idling even at high idle does not bring the oil temp up enough to evaporate the condensation (water) from the oil and that the unit should be driven not just started and idled. Maybe I misunderstood.

Is it not similar to exercising the genset monthly at idle or at the recommended 50% load.

[RVwheels]

Into the discussion. I just changed oil in July after 4yrs in the engine (ISL400 Cummins). I am a full-timer so on the move quite a bit rarely sitting longer than 4-6 wks. I pull an annual oil sample/analysis which has reported "Acceptable for continued use". I have clocked over 70,000 miles. I used/added around 4qts +/_ yearly during that 4yrs. Yes, I use a synthetic (brand name I'll leave unspoken). However, I do also use duel-bypass remote oil filters (another item you will find on many trucks). Only reason I changed last July, opportunity and comfort level. Next time, who knows? Just watch those reports/analysis. I do my own work, grease, fuel filters, transmission, differential, coolant, etc.
Obviously, I'm not afraid to extend that change interval!!

[Clonetrooper]

Jim, You could start and put in gear with parking brake on. This should load the engine enough to get condensation out. Not much different than sitting in traffic.
I use my M all year so I'm no expert.

[radams]

Originally Posted by OneRVer

WoW good questions. The stored unit will get condensation which will up the acid count. If the stored unit is being started for a couple of hours each month that should take care of the condensation.

After the filter is used for a year, it does not filter as well as it should, some better than others but the filtering will slow down. Oil stll good, just needs a new filter.

Attachment 6271 This is a good artical for newer diesel engines.

So, is the oil system on a diesel engine an open air system where air can freely enter? If so, then I will posit that both engines will generate similar amounts of condensation. Given that water boils at 212F will the engine reach that temperature sufficiently long to drive off the water vapor? Will the vapor have a path out? If it does won't that concentrate any acids and make them more corrosive?

The dirtier a filter gets the finer the particles it will trap. In a perverse sense it does better as it gets worse. Flow of course will be reduced but is there a way to measure and manage it? How about the oil pressure gauge? Is it similar to the gauge on the air filter that interprets the pressure differential across the inlet and outlet and thus tells you when the flow is overly restricted? Any chance that the engine manufacturers make their oil change recommendations while taking into consideration projected solid content and filter life? If so, it might be a real good reason to use the engine manufacturers replacement filters. Who better to know how to design the appropriate filter than the engine manufacturer? There is more to it then the size of the holes. Why then would they say 10,000 miles if their filter would be plugged in half the time?

Okay, your turn!

[OneRVer]

Originally Posted by Elkhartjim

My understanding that starting and idling even at high idle does not bring the oil temp up enough to evaporate the condensation (water) from the oil and that the unit should be driven not just started and idled. Maybe I misunderstood.

Is it not similar to exercising the genset monthly at idle or at the recommended 50% load.

Good point Jim, but I do reach 160 degrees which is the temperature that my manual says I should be at before shutdown. However, I have had to wait up to two hours to get to this point. I will also cycle the transmission between D and R a few times during this period just to work the pump a little bit.

Weather permitting I will take it for a drive, but with our winters that does not happen very often.

[radams]

Originally Posted by OneRVer

Good point Jim, but I do reach 160 degrees which is the temperature that my manual says I should be at before shutdown. However, I have had to wait up to two hours to get to this point. I will also cycle the transmission between D and R a few times during this period just to work the pump a little bit.

Weather permitting I will take it for a drive, but with our winters that does not happen very often.

If your oil temp is 160F, and water boils at 212F and turns to vapor, how is that going to work to remove the water?

[OneRVer]

Have you ever looked over a lake on a cool morning and watch the mist rise up off of the water or have you ever spilled water on the floor and minutes later it has dried up or how about when the DW hangs the clothes on a clothes line?

212 degrees is what it takes to create steam. Not to remove condensation.

I am not trying to be a ___, please do not take it that way. Just not sure what answer you are looking for.

Yes your oil has a breather tube. Also known as the slobber tube.

[radams]

No, I understand the intent of your answers and I appreciate the info. Given that this water is under 34 quarts of oil though would that change the dynamics? That lake nor the spilled water wouldn't just evaporate would it if it were under oil?

Please don't take my posts the wrong way either. I'm just trying to think about all this in a logical way and see what you guys think. We all have preconceptions and I thought it was time for me to examine some of mine.

[OneRVer]

Hmmm, good point. I have never thought of it that way. The only thing that comes to mind is when the oil is circulating and is hot that will evaporate the oil.

But as you can tell, I am just guessing. When you think about it, I have read where some people on this forum will put oil, cooking or baby, over the water in their battery to keep the water from evaporating.

Must be the heat and the circulation through the engine???? Man, I have to think about this one.

Any help out there??

[UltraKen]

Originally Posted by OneRVer

WoW good questions. The stored unit will get condensation which will up the acid count. If the stored unit is being started for a couple of hours each month that should take care of the condensation.

After the filter is used for a year, it does not filter as well as it should, some better than others but the filtering will slow down. Oil stll good, just needs a new filter.

Attachment 6271 This is a good artical for newer diesel engines.

Not quite.

Just starting the engine will not bring it up to full operating temperature. You need to drive the coach about 50 miles once a month to reach operating temperature and ensure proper lubrication. If you don't get it up to operating temperature your are less likely to get the mositure out of the engine, oil, and exhaust system.

CAT says change oil and filter every 10,000 (or 15,000 depending on engine) OR once a year, whichever comes first.

[Clonetrooper]

OneRver,
When I am trying to figure something I use the extreme thought process.
on this one i would use at one end ice, very cold water. At the other end boiling water or steam, very hot water. Water evaporates at different rates, I'm sure there is an ex rocket scientist on here that could tell you rates vs temp, I'm no rocket scientist. The oceans evaporate, hence clouds. Anyway, water evaps at different rates due to temp, even ice evaps. Went to get some ice cubes out of my moms freezer ice trays one time and the cubes were shruken. She doesn't use much ice, probably been in there a year or so. aka freezer burn. A warm cup of coffee will steam in cool weather, evaporation. That cup of coffee is maybe 120 or more. I measured pavement and concrete temps the other day with infa red thermometer, use it for my tires, the ground temp was 140 or so. I gurantee you a drop of water would be gone in a few seconds/minutes. Used to work around EMD diesels. They are fairly large two stroke diesels, they have water cooling lines that go to every cylinder, 16 or 20, these lines tend to leak and dump cooling water into the 300 or so gallons of oil in the pan. If this happened instead of doing the right thing and changing the oil we would steam the water out by propping opening a valve cover, about 3' x 8' on one bank of cylinders and let the water steam out. Normal practice on these engines, they ran about 160 water and oil temp. Anyway to answer the question, the condensation will be circulated with the oil and steamed out. The hotter the oil the quicker. If you notice milky like oil around your breather tube when running engine, you have condesation in you oil.
Just my view on this topic.

[Clonetrooper]

Just more babbling... the oil going to pump is sucked from the bottom of the pan and oil is moved around in pan by the crankshaft weights spinning into the oil and splashing oil onto the cylinder walls to lubricate the piston rings. That is one of the reasons why oil level is kept full. Any condensate will be mixed thoroughly with the oil.

[UltraKen]

Originally Posted by Clonetrooper

Just more babbling... the oil going to pump is sucked from the bottom of the pan and oil is moved around in pan by the crankshaft weights spinning into the oil and splashing oil onto the cylinder walls to lubricate the piston rings. That is one of the reasons why oil level is kept full. Any condensate will be mixed thoroughly with the oil.

I'm not sure what your point is but any water "mixed" with oil will quickly separate out. If you lubricate the cylinder walls with an oil/water mix do you think you will be getting the same degree of lubrication as with oil only?

I still think the economics are different for fleet operators Vs private coach owners. The fleet operator has engines that are in constant use (water is being constantly "boiled out") and bugets for engine repair/replacement costs which are deductible costs from profits.

The private coach owner has an engine more prone to intermittent use and generally a smaller budget for repair with no tax reductions for operating expenses.

And finally, the engine manufacturers and their engineering staffs tell the private operator to change the oil and filter at least once a year. If I trust them to build a good engine why would I not accept their judgement as to proper maintenance?