Some things I have learned about my new 2019 Cornerstone - Part 5

[Gary.Jones]

Gsman

Thanks for the report. I knew you would be able to get a real world idea of temps. The 181 degrees for coolant seems right on. The 225 is about 10 degrees lower than I routinely got with my old oil temp sensor and the number (225) falls in an acceptable range. My first sensor typically read 237 +/- but something was throwing false readings (or real readings up to 276 degrees) and my new sensor seems to be reading normal temps even higher. As I say, I backed down on highway speed when it hit 250 degrees.

I am going to have a phone call with Spartan upper level engineers today and we will talk through what could be producing these higher oil temps. This is the first time in my life that I have even thought of a problem in oil temp. My understanding of an internal combustion engine was that the oil was moved through the engine by a simple gear mechanism which then drew oil out of the oil pan and pumped it through the engine block lower piston area. I never knew it had any part that could fail. I am going to have to read up on the presence of an oil thermostat and an oil cooler. I have no idea if those are in the engine or not.

Thanks for the comments so far. Any further discussion of engine oil temp regulation would be greatly appreciated.

Gary

[Rollin101]

Gary, I can promise you that you have an oil cooler. Even pickups with small gas engines have oil coolers.
I think most truck/auto engines oil coolers are air cooled. If you ever get a jet in that thing they have both fuel and air cooled oil coolers.

[Turbojack]

While you are talking to the engineers today also ask them if you should get the oil changed right away.

I had learned the hard way that if your oil get real hot (cooks) it will start to gel up

[Gary.Jones]

Jack and JH

I will discuss both of those issues with Spartan today. There is a Speedco here in Casa Grande and is certainly a thing that I can get done.

Thank you

Gary

[Gasman 2]

Gary, after thinking about your issue I wondering about the oil itself. I sure you have checked the oil level, has it showed any indication of the level increasing? I would look for fuel dilution or coolant.
Neither one good but you’re under warranty.
There have been problems with the EGR cooler leaking coolant into the oil. I’m not just speaking of the X engine.
Just don’t overlook anything.

Please keep us updated.

Richard

[Gasman 2]

Originally Posted by Gasman 2

Gary, after thinking about your issue I wondering about the oil itself. I sure you have checked the oil level, has it showed any indication of the level increasing? I would look for fuel dilution or coolant.
Neither one good but you’re under warranty.
There have been problems with the EGR cooler leaking coolant into the oil. I’m not just speaking of the X engine.
Just don’t overlook anything.

Please keep us updated.

Richard

I miss spoke about the EGR leaking coolant into the oil. If EGR is leaking coolant it will be into exhaust stream.

[Gary.Jones]

Richard

I checked my oil levels this afternoon which also gave me a chance to feel and examine the engine oil (Rotella). The engine oil is at exactly the top of the full level on the oil dipstick which is where it has been all along.

Also, while the oil is black (I have about 13,700 miles on the coach), there appears nothing different or changed about the oil thickness or consistency (of course, it would need chemical analysis to know clearly).

For whatever reason, I never got a call from the Spartan people today (although I pushed to get some feedback) so I know nothing more officially about the future of my problem than I did yesterday. I am personally more convinced that I will be heading to a Cummins CoachCare facility or Cummins engine shop. Time will tell.

Gary

[Gary.Jones]

I posted this information in another thread on here, but since it contains information direct from Cummins that I have not seen presented here, I will copy and paste it here so that all finding this thread will have it.

Because it is part of a longer post, it will seem disjointed, but keep reading and the good stuff come through clearly.....

---------------------------------------

" When I last wrote, we had left NIRVC in Phoenix after a new Hadley controller, Fisher-Paykel, and AH exhaust pipe were installed. Still up in the air about the over-heating. Armed with this information, we departed. I was told by Cummins people in Phoenix that if my engine oil temp got about 250 degrees that I was getting close to shut down temps. So, I started from Phoenix to Casa Grande to spend some time in an RV park/resort (not a repair shop....). Watched oil temp gauge on dash constantly and temps gradually crept up to 237 (what I saw on the old temp sensor) and then up to 242, then 244, then 246, and then 248 alternating with brief periods at 250 degrees (a second or two). But 250 was my understanding of getting serious. My coolant temp sat at 180 +/- 2 degrees with the fan now turning itself on and off as needed. I was driving at 68 mph and so slowed to 58 mph to see what happened to my oil temp. After about 10 min of vacillating from 248 to 250, at 58 mph, the oil temps started to drop, but still in the 246-250 ballpark. So, I slowed down to 55 mph for another 30 miles. This was not looking good (I was doing a nice imitation of a 1976 Winnebago Chieftan) . Oil temps fell back to ~ 240 by the time I arrived in Casa Grande, so that was good. Checked oil viscosity and it was normal. Engine oil level was exactly "full" so no new liquids in the oil, and oil color and consistency looked normal (black, slippery). Spent a week here just relaxing and not worrying about the coach but then needed a 4- or 5-way phone consult with my main CS guy at Spartan, plus some others at Spartan, and then a Cummins guy who was further up the chain.

I described the whole thing and then the Cummins guy told me that I had been given a bunch of wrong information. First, he said that temps up to 260 degrees were nothing to be concerned about. He also told me that the X-15 605 HP Cummins engine has an oil cooler system and an oil temperature thermostat that opens at 260 degrees and at 260 degrees permits oil to run through the cooler and lowers oil temps. Well................. THAT is important new information for me and for everyone else that runs this engine. The oil thermostat and cooler does not even kick into gear until 260 degrees. The Cummins man said, "Don't worry about temperature and drive whatever speed I wanted to drive". He also confirmed my impression that this X15 and its predecessor ISX-15 likes to run faster and hotter than my old ISL-450. That has been my experience.... my coach seems to be happiest at around 70 mph, but when I drive at 68 or 69, things are good, revs are right, and it handles many hills without losing more than 25 revs in engine speed. So, mark that down: Oil Cooler system and oil thermostat don't kick in until you hit 260 degrees.

Now remember, I never saw temps higher than 237 when I got 3 successive Shut Down Alarms on I-10 on the way out here. My dash showed no temps anywhere close to 260. Yet, when Cummins pulled the "historical data", the historical engine data said that I had hit 276 degrees three times. The assumption was that the oil temp sensor was defective and it was replaced. Then a mechanic told me the 250 degree danger point, which was not correct. Maybe 270 or 265 is getting close to a shut down danger point, but 260 just opens the thermostat and loops in the oil cooler. So, the assumption is that I did in fact have a faulty oil temp sensor.

Time will tell now if I have future problems. I plan to drive it like I stole it and assume that it will take care of itself.... We shall see. Hopefully my "1976 Chieftain days" are over!" ( I apologize Chieftain owners....)

Gary

[Turbojack]

Great information.

Did they give you a clue as to why you never saw anything that high on the dash? Two different sensors? I for dash and 1 for engine?

I am going to guess if the problem happens again it will be the oil cooler thermostat.

I do know on mine which has different engine then you do that I get better mileage at 70 then I do at 65. Some point slower then 65 the mileage gets as good as or better then @ 70

[Gary.Jones]

No, forgot to try to button-hole them on that. Here is simply a guess.

1.) CUmmins said there was nothing wrong with the oil sensor, but they replaced it anyhow since I was having so much trouble.
2.) I have been having trouble with CAN-BUS and RADAR problems for 3 or 4 months now and that is either explained by a bad WABCO RADAR motherboard unit/or water intrusion connections, or the CAN-BUS itself.
3.) The ACC and CMS has been failing frequently.
4.) The VALID digital dash showed one temp as you noted and the engine ECM showed a much higher value (which makes no sense unless the oil thermostat and cooler are fried also) and the dash has its own sensor (unlikely).
5.) The Shut Down alarms/faults had disappeared by the time I got the coach stopped on the berm
6.) I got a BUNCH of crazy errors from the rear end of the coach (missing data expected, inconsistent data about what the drive tires were doing, missing MPH readings on the speedo, ABS quickly pulsing on and off, engine de-powering itself on fairly minor slopes, etc etc. it has been a cornucopia of strange faults.
7.) Spartan has decided to pull out all the stops and look for a bad connection, loose solder joint, etc etc on the CAN-BUS.

At this point, if I had to bet $1,000 my chips would go back onto bad CAN-BUS connections. JMHO. Your guess is as good as mine.

Gary

[Turbojack]

I have been doing some reading on the internet. I know it is dangerous. I could not find any discussions on the x15 engine but found a number of them on the isx15 Sound like the oil temp thermostat is set lower then 260 and 250 in the pan is a temp to be concerned about.

I would like to see what other are running as oil temps. Maybe make a thread as to what are your oil temps and see what they are out there beside just Entregra. I am going to do a post on another forum I am on.

[Gasman 2]

Gary,
Here’s what I have been told by the tech at the Freightliner dealership. 220 to 225 would be normal, 275 would be high.

With that said the oil temperature gauge on our 579 Pete begins to red line at 250.
But all of this is trumped by what your Cummins guy related to you. I know this does help clear the issue up.

As a matter of checking, today the Pete was in the yard after running all night. When I came in this morning it had cooled down so I started it up and watched the oil temp come up to 160 and took a infrared thermometer and started to check different places on the engine where engine oil would be, the oil pan, oil cooler, oil filter and the base of the oil filter and the location I found to be consistent with the dash gauge was at the oil filter base.

So if you have a infrared thermometer you may want to check that against what the dash read out is.
So you can take this for what is worth or as you said run it like you stole it. [emoji16]Hopefully the Cummins guy puts that in writing.

Richard

[Rollin101]

The Cummins rep should know, but I’ll be really surprised if the oil cooler thermostat starts opening at 260deg. All oil temps I’ve seen run in the 220-230 range, time will tell.

[Turbojack]

Just got off the phone with a friend of mine that troubleshoots, works on 1-3 million dollar industrial motors. He said most oil pressure gauges are the temp of the oil as it is leaving the oil cooler or filter. He said oil goes from the pump to oil cooler and filter before it goes to anything else. He said some go to filter first then cooler, and some other way around. The oil cooler is bypassed until the oil get to the oil thermostat temperature and then starts going thru the cooler. Reason for bypassing the cooler is to get the oil to operation temp quickly. With Gassman2 finding out the oil filter base was the temp of the gauge makes sense now since that is where the gauge is reading. The engine oil may have not been up to temp so the cooler was closed so that may or not be the best place to check. My guess is to check on the output side of the cooler after oil has gotten hot. He felt 260 was pushing the oil to close to it's limit since where it is check is as cool as the oil is going to get. He also said that the pan is often times 20 + degrees warmer then on the output of the oil cooler before going thru the engine.

Now since we do not know where Cummings is checking the oil temp and if they are checking in the pan then what Cummings rep says would make more sense since the oil there is 20+ degrees warmer. I do not think the pan would be a good place for the temp probe since it might be too late to know if your oil cooler failed or failing.

He also said oil is cheaper then a new motor, if the coach was his and the oil really did get that hot he would change it.