I know . . . I'm not losing any sleep over it. :-)

It is, however, an interesting intellectual exercise.

 

So the news is that International Lubricant Standardization and Approval Committee (ILSAC) has identified timing chains on direct injection engines to be inherently problematic. (not the tensioners) due to improper lubrication

They are proposing that some test be developed to measure the wear on the chain. And that wear number is going to be stated on the oil in the new GF-6A Specification. More importantly they want all oils to be able to control some degree of chain wear.

(chain wear has now been pinned on accumulation of contaminants in oil and dilution of oil by gasoline)

Its great news for some of us is that we were pointing out that timing chains on DI were lasting a third as long as conventional engines. Now its been confirmed.

No your mail-order oil test is not going to show this. But it can once the standard has been set.

No they dont say change your oil more frequently. Remember they are not talking to the public, this is for within the lubrication industry i.e oil manufacturers like castrol.

You can draw your own inferences as to what you can do to get a jump on things.

 

The Timing Chain-wear Test
Why? The Timing Chain-wear test is another brand new test and is being developed in response to new engine technology. Contaminants from combustion enter the lubricant sump as a result of blow-by and accumulate in the lubricant leading to increased chain wear. Also like the LSPI test, a Ford 2.0 liter EcoBoost engine will be used to run the chain-wear test.


What does the test accomplish? The test will effectively measure a lubricant’s ability to minimize timing chain-wear as it relates to the soot-like material particles produced by GDI engines.
How Lubrizol is staying ahead: Lubrizol is actively involved in the development of this test. The greatest challenge here involves accurately recreating the field severity of an engine dyno that accurately and repeatedly reproduces chain-wear.
In all, the inclusion of six new tests in the proposed GF-6 specification is a drastic change from that of older specifications, necessitating major investment from industry stakeholders. The implications for oil marketers are severe, and the new tests will require innovation and dedication to keep pace. Each test has its challenges, and through industry collaboration and innovation, those challenges will be met.

 

On a side note, is the F-Type supposed to be broken in? Or does it come ready to race from the factory?

 

You can spend the money and time on testing the oil
... or just change the oil.

I think the second is more productive.

 

So why, with all that "highly scientific manner" does the
problem even exist? According to your assertion, the
problem should have been foreseen and dealt with
before adoption.

Hubris wouldn't have anything to do with it, would it?

 

Ahh ... but according to Lubrizol who are one of the dominant, if not the dominant,
creators of the necessary technology, the commercial realisation of the solution
is both an unknown quantity, and many years away. More years than the timing
chain will last. So for today, whether or not better oils are required, they
are just not on the immediate horizon.

Now, if you accept that soot loading is a contributing factor to the accelerated
chain wear, do you adjust your oil changes to avoid the problem, or do you
insist on going to 15K?

Say you staged your blown BBC and the big red low oil pressure light came
on steady ... do you ignore it so you can run and perhaps win ... or forfeit
the race to race another day?

 

If you truly are curious, you could go to bitog and scan as
many posted UOA's as you can stand. Forget the commentary
in the followup posts. Just read the UOA's.

Most of them are from Blackstone Labs. They have a habit
of commenting on whether or not the subject vehicle could
safely extend their oil change interval based upon the
condition of the oil.

You won't find very many where the oil has gone 12K and
the lab suggests going further.

I know that an engine can go further than 15K without changing
the oil as long as the level is replenished. I also know that
the same engine blew a rod through the side of the crankcase
at some point further than 15K. It was a Toyota with the
DOHC 2.0L which is generally thought of as being very
reliable. It was not low on oil. It just didn't like the
age of the oil.

 

At least Saab and Alfa Romeo had this licked
decades ago. They used gear driven mechanical
injection. No computers, no fuss, no muss.

If you could get the Saab to turn at least once
on a flat battery in sub-arctic weather, it
*would* start.

 

Thanks Queen and Country,

I must admit that I was completely unaware of the likelihood that excessive chain wear, and early failure is a weakness of the GDI design. It's also useful to know that it appears to be a problem with the chain itself, not the tensioner. I also didn't know that GDI was linked to more oil dilution and contamination than conventional fuel-injector-based, engine designs.

I was aware of problems w/ excessive carbon build-up on the valves in GDIs, which I experienced in a 2007 Audi RS4 4.2L at around 20K miles. That was one of the earlier GDI engines.

I'm assuming that the GDI oil contamination issue is more mileage than age-based. I'd be interested in hearing your thoughts on that.

My car will receive it's 3rd oil change in June at about 10K miles when it will be 2 years old since delivery. The last oil change will have been 1 year and 6K miles ago. Since, we rotate between 4 cars w/ 2 drivers, we don't put a lot of miles on any one car, but I do generally drive the F-Type at least 120 miles a week averaging about 30 miles per trip, mostly highway.

I don't generally keep new cars past the warranty period, so these kinds of issues aren't usually a worry for me. However, I am leaning towards keeping the F-Type long-term.

 

This is not exactly correct. There is nothing wrong with the chain design, it is limitation of that technology. This is like flat tapped cam followers - it is basic design that could not be taken any further. The solution was perfecting roller followers.

The solution is dual-row chain or some exotic ($$$) materials until better oil becomes available.

 

Give me a break . . . sure "nothing wrong with the chain design" in a conventional engine, it just doesn't appear to be as protected by current lubricants in the GDI design. So that poses a dilemma for manufacturers, either come up w/ a design that works better in GDI or find a better way to protect the current design.

Taking sentences from an entire post out of context allows you to distort the intent of the entire message any way you want.

 

Foosh, my apologies I had no intention of distorting your post.

My point was that any engineer, and not just JLR, would have taken standard engine chain design for specific power and configuration, slapped it on the engine and had no reason to believe that it would be a problem. It also won't show up in testing, as chain stretch is gradual and the system seamlessly copes with it up to a point. Unless you specifically test for this (as per Q&C posts) you won't know this is happening.

Actually, very similar issue happened with Mercedes M116 engines. They installed single row chains, had a bunch of them fail, and switched to a dual-row timing chain that mostly solved the problem. I actually have an SL with that engine that was manufactured with a single row chain, was converted to dual-row chain as part of Mercedes campaign and is still working after 30+ years. By now I am on my second dual-row chain.

To make it more interesting, for some reason US-spec SLs suffered disproportionate share of chain failures. It was uncommon to see it fail on EU or gray car, with many still running single row and after about 15 years all unconverted US cars suffered failure. Maybe difference in fuel formulation, or emission tuning, or oil formulation, or something else?

Either way, most M116 engines survived this ordeal, with community warning every new owner to keep an eye on the chain. The same will likely happen with our F-types.

 

There is a shocking revelation if we read between the lines. Read it as if you were the oil manufacturer being asked to formulate towards a new target. Apparently pollution is the only god. Be damned the reliability. You can see that in the opening statement- they want more GDI despite lower reliability.

They want to reduce chain wear because it affects timing and emissions, not because its a new burden on consumers.

Even the oil grade and the length of usage is environment centric- not car centric.

Then again whats new, egr was never for the good of the car.

 

Hi Foosh,
The chain problems I have seen are all at low mileage. However, one constant has been is that they were 2nd owner cars. With no real knowledge of the original owners driving/maintenance habits.

You should keep the Ftype, one take away is that cars will only become more complicated and less glamorous. It has it all, and truly stands apart with its mix of rich heritage and advancement. Incidentally, Ian has said this is the last time the Etype or any iconic Jaguar will be referenced in the design of new cars. You can tell by the XE and SUV, they are now more interested in chasing BMW than being original.

You do the most important thing in maintenance, which is to take it on the Highway weekly. I cant, the highways here ( city in southern USA) are more clogged than the secondaries. Traffic is just insane.

In one aspect there is little to worry about, since is a known problem, and will be covered with warranty. Even out of warranty, it really cost no more than 30k service on a Ferrari. And yes your car is in its league. If JLR was as inefficient in manufacturing as the Italians this car would cost more.

 

Since Pascal's Wager was referenced, do you guys know about Bubba's Wager?

Bubba and Sebastian while on an expedition are captured by an African Tribe for trespassing. The tribe chief offers them a choice of bula-bula or death as punishment. Sebastian selects bula-bula and is subsequently raped by the tribe warriors. Bubba picks death and the chief says "so shall it be, death by bula-bula"

 

I'm not trying to be contentious, but I don't understand. The test does specifically measure dilution by fuel. It also measures a variety of contaminants. What specifically is not being measured that should be?

 

Saab automobiles didn't use gear-driven mechanical fuel injection. Fuel pumps on injected models were always electric. First was D-Jetronic, then K-Jetronic, followed by LH-Jetronic when the 16-valve engines came out.

I think Alfa Romeo did use mechanical injection, but am not certain. We (my shop) specialized in Saab.

 

Nano particles of soot. That are very difficult to measure. They know without a shadow of the doubt that these nano carbon particles grind down timing chains. What they cant figure out is if they also reduce oil's anti-wear additives. Standard tests thus far cant detect either. Here is one done with an electron microscope.
Characterisation of soot in oil from a gasoline direct injection engine using Transmission Electron Microscopy

They want to simplify it for consumers and say this oil is less affected by carbon particles and extends chain life.

 

This brings me back to a question I raised this morning regarding whether the GDI/chain/oil issue is primarily mileage-based or time-based. You didn't comment on that.

If it's "nano" carbon particles blasting away the timing chains in GDI engines, and since carbon is a product of combustion, one could reasonably deduce that more miles driven produces more nano carbon in the oil, which leads to more chain wear. Thus, a car driven 5-6K miles between annual oil changes should be safely within the margins, wouldn't it?