One oil change in 11000 miles?

Yeah, they pretty much gloss over the iffy parts of those rotary valves, like lubrication, thermal expansion, and wear of non-lubricated parts. Looks like something you's see on a crowd-funded website to lure in "investors". :)

free radical wrote:
Something interesting for you technical types,Coates Rotary Spherical Valves which not only improve breathing capability of an engine icreasing hp but also reduce the need for frequent oil changes..
Whats mind bogling that none of our car manufacturers would use it..

Rotary valves of various kinds have been around for ages and ages. Generally their drawbacks for engines are difficulty in maintaining seals and possibly in wear. This particular implementation would seem to me to have poor wearing qualities, with the bearing surfaces apparently being unlubricated bronze bushings. You can bet that if they had significant advantages over current valves they would have been adopted by car makers who go to great lengths to improve fuel economy by little bits (a fraction of an mpg here, a fraction there).

Rotary valves do have other applications, such as plumbing and some brass musical instruments. My trombone's F attachment is controlled by a rotary valve, as a matter of fact, as are my washing machine's water supply connections.

Something interesting for you technical types,Coates Rotary Spherical Valves which not only improve breathing capability of an engine icreasing hp but also reduce the need for frequent oil changes..
Whats mind bogling that none of our car manufacturers would use it..
Too late now anyway,Chinese bought all the rights

http://www.coatesengine.com/csrv-advantages.html

The CSRV System is comprised of only two moving shafts and does not utilize oil pressure fed bearings, or oil spray; in fact, no engine oil is present in the head of the CSRV Engine.
This means the engine oil does not see the hottest parts of the engine, which was the exhaust Poppet Valves.

These extremely hot components usually are engine oil spray cooled. This heat would breakdown the atomic structure of the engine oil, thus lowering the oil viscosity, therefore, oil changes are recommended every 3,000 to 5,000 miles.

On the other hand, with the CSRV incorporated in the engine design, oil change intervals are extended to approximately 50,000 miles or more.

http://www.coatesengine.com

Grit dog wrote:
Some of you people crack me up with 2000mile oil changes and the belief that if an engine sits longer than 12mo without an oil change that it is going to magically self destruct.


Does this raise some "chance" of engine damage or reduced service life?

Yeah, the engine will probably only go 200k miles instead of 300k before needing a rebuild.


Of course the coach will probably never see anything near 200k miles before it’s scrapped, but that’s a whole other silly argument.........

I’ve got a Kubota tractor I bought when it was around 15 years old with about 500 hours on it. It came with ‘all the service records’. The break-in oil was changed out at 50 hours when it was 6 months old, and the oil was changed again at 100 hours when it was a year old.

That was the last oil change done until I bought it about 14 years later.

It now, another 12 years later, has about 6,000 hours on it. Other than changing a battery it has not needed ANY repairs in all that time and still has oil pressure and compression are well within factory spec.

The sky has still not fallen.........

Some of you people crack me up with 2000mile oil changes and the belief that if an engine sits longer than 12mo without an oil change that it is going to magically self destruct.
YES, the time based reccomendations are to enhance longevity by not storing old oil that may have compromised lubrication properties, but that is about as far from an absolute as a trip to the moon.
I have machines that I baby and they get an annual oil change regardless of hours (the boat) and machines that get an oil change after every use (4s MX bikes). I also have machines that haven't seen an oil change in many years (jeep) that gets driven seldomly to not at all.
I've never seen physical evidence of failure or even anecdotal evidence of failure due to exceeding time based OCI reccomendations.
This across fleets of hundreds or thousands of engines of all different types throughout my career.
Does this raise some "chance" of engine damage or reduced service life? I'm sure it does, but I don't know the probability any more than any of the chicken little sky is falling posts saying it will blow up 10 min after you get the title signed over.
It's a risk vs reward thing. What's your tolerance and can you build the tolerance into the sales price? It's a gasser, so engines are comparatively cheap. Can you get it for $5-10 grand less than a comparable unit that has had extra oil changes? That much in savings will partially or completely recover the cost of an early failure down the road, IF you ever have an issue.

MrWizard wrote:
the coach was garaged , clean, and well taken care of

the owner is NOT an idiot, forgetful an non-informed ?

but not an idiot

And you know this how exactly? Personal friend of yours? I have a bit of news for you. IF you spend six figures for a piece of machinery, and can't even be bothered to give that piece of equipment the most basic of low cost care, you do not own anything that is, in your words, "well taken care of" AND you are an idiot. Sorry, but it is what it is.

I would say that if its been sitting since the oil change then it should be OK. just change the oil and be ready to go. I don't think its as big a deal as some are making it out to be!

the coach was garaged , clean, and well taken care of

the owner is NOT an idiot, forgetful an non-informed ?

but not an idiot

MrWizard wrote:
It did not go 11,000 miles
It went 6000 and was changed
And is now at 5000 more, and ready for another oil change

According to the first post

Find a manufacturer of any vehicle, chassis, or gas engine that specifies that you can change your oil once in twelve years of service? This thing has been abused and neglected, and nobody with half a brain would think it's acceptable to let any engine that accumulates an average of less than a thousand miles a year end up with ONE oil change in twelve years of service. BTW, the workhorse repair manual of that era calls for an oil change every three months or three thousand miles.


http://www.irv2.com/forums/f22/workhorse-gas-chassis-maintenance-schedule-26028.html

Extreme, IMHO, but a bit different that "and now after 5-6 years of being neglected, and accumulating acids and condensation in the crankcase, it's ready for another change". No, now it's probably ready for $10K+ in repairs and maintenance to compensate for the fact that it's been abused by an idiot of an owner.

JIMNLIN wrote:


JMO but some folks waste good engine oil. Engine oils today aren't from the '70 era thankfully.

The issue that the OP asked about was not miles, but rather the many years between changes, somehow that keeps getting missed.

Many respect the services from Blackstone Labs. They did testing on decades old oil purchased on eBay. Interesting 3 part article and the bottom line was:

So that’s the end of our series. A lot of thought goes into making oil, and that’s been the case for many decades now. We’ve poked some fun at the way oil companies sell their products, but heck, they’ve got to say something. We stand by our statement that “oil is oil” and in the end, it doesn’t make a lot of difference what you decide to use. Through all the years and all the permuta-tions andconfigurations of oil and oil additives, the crude (and now, synthetic) stuff has kept cars running since Henry Ford did his thing more than 100 years
ago. Buy what suits your vehicle and your wallet -- not what anyone else says you should use.

Part 1

Part 2

Part 3