Bill Faure

NO, I only have a BS in Engineering Technology. However, to get that degree I had to take 3 levels of chemistry. That's how I know when the chemical equation for internal combustion is written out carbon is created/left over. Motor Oil can turn black for many reasons. The main one being the carbon left over from internal combustion is suspended/floating with in the oil. Since carbon is molecularly heavy given enough time it would fall to the bottom of the oil pan and the oil itself would keep its golden color. However, as we all know that isn't the way automobiles are used. The carbon floating in the oil is constantly being churned up and more is being added every time a cylinder fires. When you change your oil you physically remove most of the carbon created by internal combustion. That's why people think it is good to change your oil more frequently. However, with modern fuels (lead free) the carbon desposits that are created from internal combustion are very, very small (microscopic). As such the amount of carbon that "floats" in the oil takes longer to accumilate. Thus longer drain intervals. As mentioned oil that's heated to 300 degrees or more creates parafins. You'll recognize that name from candles. Parafin is a wax! You can imagine that wax inside an engine is not good. Black parafin buildup creates friction instead of preventing it. Thus the engine in ERICL's pictures. However, ERICL it is ok to have a part in an engine reach 300 degrees. They often do. What is not good is to have the lubricant reach 300 degrees! There's a difference! I hope that helps, but I'm out of time.

Juker008

WOW I found my long lost brother .

Ur statement is ture to a "T". Carbon molecules are far too small to be captured by an oil filter, even micon-oil filters.

The fact that the carbon is heaver than the oil and would fall to the bottom of the oil pan is very true. But I don't believe that would help much, since the oil slump's inlet rests so close to the bottom of the oil pan, to prevent oil starvation.

But never the less ur statements are correct.

But let me ask u a question of prefrence. Do u run with synthetics? If not or so do are ur drain intervals at 3K?


Juker008

EricL

Part I:
Engine == spark fired internal combustion engine from a BMW OK?

Spot heating and head temperatures -- you don't know what they are without a cylinder head temp. gauge. I built about ten of those engines (with variations) and the final solution (for all-weather cooling) was runing higher compression (less heat rejection), with a modified cooling pump, a giant water radiator, add-on oil cooler, and thermo controlled electric fan. (Even with the mods and minimal temp rise, there was a lot of heat generated right above the combustion chambers == localized heating).

Now don't you find it remotely interesting that engines with conventional oil ALL had varnish and coke and ALL the engines (even those without cooling mods) had no signs of junk (in the heads) when using synthetic????


The point is this: some rather good conventional oil got changed like clockwork and came out looking way to clean at 3K mile intervals. So, what you don't know CAN hurt you. As for the exceptions and so on, there are some blanket statements that are being made and there is an implicit assumption that the stuff I was staring at MUST NOT HAVE BEEN COKE. Having spent more than enough time scraping wax, varnish, coke/carbon, and other substances off various industrial combustors that we were working on, I can feel quite confident that what I was looking at was COKE!

The engines where never ran dry or low on coolant. The millisecond they did, they cracked the heads...

So, if someone (you) want to make a point that most of the new water cooled vehicles (especially Japanese) don't have red-hot heads -- yeah, they drive in the summer traffic with out trouble. However, it is possible with air-cooled and under high loads to have very high spot heating. There are NACA studies that date back to WWII where cylinder temps were run in the 400-600 degree range on air-cooled radial engines. Planes are not meant to be towed home.

So, if you ever are curious about some of the possibilities of why you can have COKE inside an engine that has nothing to do with combustion processes or gas, I'm telling you that it happens.

Does your car have a cylinder temp gauge on it? So, perhaps it does or doesn't get too hot... Will you ever know for sure?

The wear that was done to parts that relied on spray lubrication in the topside of the head were worn to death do to the very high abrasive properties of coke. It isn't graphite -- get some into a piece of stainless and rub it around -- you will find a bunch of scratches -- just what cam lobes and rockers don't need.

You’re arguing with my first hand experience and I'm hearing that motor oil will never coke up and the substance must be “benign”. Please…. If you ever get an air-cooled engine, a car with a turbo, or a engine with a some “hot spots” you might want to invest in a cylinder temp gauge. The ones available read up to 600 - 750-degrees F


That’s why I changed to synthetic -- it solved a problem that people are telling me can't or won't happen. I find that particular galling.




(Not from a synthetic "pusher"):


"Synthetic oil is also put together the same way as conventional oil. It has a base and additives. The difference is that the base oil is synthesized so that the size of the molecules are ideal for a particular weight and are of consistent size. Conventional oil has many molecule sizes all mixed together with many impurities, but there is an ideal size for the best lubracative properties and viscosity. With a pure base, there are no waxes or impurities that contribute to buildup of "varnish" and "coke" in your engine. A more sophisticated set of additives is added to this ideal base oil. These additives make for an extremely stable engine oil which can maintain its viscosity over a larger temperature range and keeps the base oil molecules from breaking down. The result is an oil that can flow at much lower temperatures, maintain proper viscosity at higher temperatures (thermal breakdown), and remain stable for a much longer period. It will also protect your engine longer at and right after startup because the friction inhibitor additives are activated a lower temperatures than that of conventional oils"

And defs:

(Not a synthetic pusher)
http://www.walnutcreekhonda.com/glossary_terms.htm

Coking
(a) The undesirable accumulation of carbon (coke) deposits in the internal combustion engine or in a refinery plant


AND

(A site for a turbo pre-oiler)
Shut-Down - During a hot shut-down, oil flow ceases during critical turbo spin-down and bearing temperatures can reach as high as 600° F. Heat in the turbo housing migrates to the bearing. The residual oil is cooked into "coke" and the bearing surface becomes damaged by the abrasive granules.

http://www.enginelube.com/testing.htm

Graph for the few and hot drivers with turbos and way too hot heads:




There is localized heating in an engine (outside of the combustion chamber)...

fender4

I love these debates (yes more sarcasm) I'll keep sending my oil to the lab after every 10k.

Pappy

So...to sum it up, in English, guys...is the synthetic oil worth the price or not?

gmilian

omg all this fighting over motor oil. for piece of mind use synthetic, if not buy regular oil. i use redline only because i like to keep my rpms high, and redline is a racing oil. it gives me piece of mind.

fender4

If you lease or trade in after 40-50k maybe not. IF you want to get 200k plus out of a engine, synthetic's are worth it. You just have to decide what's best for you.

russianDude

To sum up, use synthetic oil and change it every 7,500 miles.
This will cost you the same compared to changing your oil every 3,000 miles. Plus you getting all of those benefits... If you read all that reasearch you might even go longer than 7,500 miles

Juker008

Listen here Meow,

There are is no fighting in debates, we are just arguing over the pros and cons and what is best. Eveyone has thier own opinions.


Juker008

Juker008

7.5K I don't know about that, personally I wouldn't go past 5K even on synthetics.


Juker008

Pappy

Maybe I'll get synthetic at 12K miles and change every 5K miles instead of 3K miles that I do with the dino oil. How's that? Like they say, "what ever makes your boat float." Right?

russianDude

Why? It depends on your driving conditions and time...
I think for most of the highway driving 7500 on synthetics is fine..

blazerbob1

What EricL said bout the quality of synthetic oil! However when closely checking oil I find synthetic oil changes to darker color just as quickly as conventional oils so change intervals are the same at 3500 for my CL-S!

russianDude

I heard color is not the only factor to judge if oil is good or bad. It all depends on the chemicals inside, color does not mean much.

If I am paying twice for synthetic oil, I am expecting to get my money worse and drive it for 7,500 miles!

SinnedTL

One thing I wanted to point out is, you said synthetics are able to capture and trap more crap than conventional oil and that you can't have that flowing through your car for too long, but THAT's why there is an oil filter, and a good oil filter is RECOMMENDED with extended drain intervals, so again your argument does not stand, I think the best way is, do an oil analysis and go by their recommended suggestions, but if not, I think 7500 miles would be good with a full synthetic and a good oil filter such as stp, bosch, k&n, amsoil and even honda filters...

Another thing, say you take conventional oil and synthetic oil on an agar plate and mix in one tablespoon of cow shit to both agar plates and stir well, well no matter what the composition of the two oils are, they are both gonna turn brown...so the burn out from the combustion of the engine is what turns oils into a slightly brown color, not that it's time to change the oil...this holds true knowing that there is no THICK brown buildup...obviously to a some degree, darker oil means that the oil is probably worse than a lighter oil with about the same miles on it...so what my point is, the color of the oil can be misleading and should not be the ONLY factor in determining a dirty oil...

fender4

One last note from me,,, I had My oil analyzed after 9600 miles..... results came back very positive and they recommended that I only change the filter. The limiter for long synthetic oil life is FILTERS not the oil itself which is very very good.

EricL

Oh, that gave me a thought....

If you get a good "baseline" to see what bearing materials are coming out (and at what rate), how would you (or someone) like to get some UR pulleys and compare the subsequent analysis to see if there is any "significant" difference in oil samples (that would point to possible bearing wear)...

Thoughts?

fender4

On engines I have rebuilt (big 60's V8s) crankshaft bearing damage was due to side loads, mostly caused by overstress on the crank pulleys. Rod bearings are usually heat damaged due to over reving (dam missed a shift on that one). Ur pulleys I believe would allow quicker time up to a RPM, The initial thrust would not be much more than stock so the internal bearings probably only feel a very small different in strain. I can match the iron material in my oil with the known composition of the bearings that Acura uses, this is more research that I might do if the iron ppm increases. Also I would have to have Acura tell me their bearing supplier.

russianDude

Let me ask you this, whatever filter Acura installs when I do my oil changes, can it hold for 7,500 miles provided that I supply my own Mobil 1 oil?

JHEIII850Turbo

Alright, guys. I just read the whole topic over, and this is what I think. I use Mobil 1 Synthetic on my Volvo 850 Turbo which has 120k miles, and this thing is driven HARD, I mean redlining every 2-3 minutes. I'm a 16 year old with a led foot. Also, the boost is turned up on this car. Oil to me has always been the best warranty policy. I asked my mechanic once, "Why should I change my oil every 3k miles?" He said, "If you have the money, do it. If you don't, I'll lend you the money and do it for you." So he's a stickler on it, and I believe him in the fact that after 3k miles your oil IS used, sure it depends on your driving style... I know mine kills engines, but hey it's been taking a beating for 120k miles and still pulls 15.0's on the 1/4 mile in 82o F heat, and hangs with Juker008's CL-S . If you have the extra $30 lying around after 3k miles do it, otherwise go to your local wal-mart, k-mart, whatever and jack the mobil 1

fender4

No probably NOT,, here's a link where filters were analyzed. As you can see most American Honda filters are not made of Qualty components. The Japan Honda Filter is made much better. I gave Todd the Amsoil filter. Note that Mobil1$10.00,, Bosh $ 5.00,,, and STP $ 3.00 are all made at the same company and seem to be identical except Mobil1 seems to have different media. There are other filter studies that measure flow rates. It's still your call.

http://www.ntpog.org/reviews/filters/filters.shtml

EricL

I don't what good this is without someone actualy "grabbing" a set of bearings and getting the analysis....

Possible candidate? --> http://dwolsten.tripod.com/articles/sep93a.html

However, the twist (when and if it happens) converts to a side load (think of a paper clip with a bend in it, when you twist one end, the other end doesn't just "twist", it moves latereraly (side load). When I mentioned this to the UR guys, he finally "got it".

russianDude

Hmn, but somehow owner's manual claims that you can go for 12 month or 12,000 miles using OEM fileter??

Juker008

Well if that was the case then the oil wouldn't be black. Oil filters don't catch everything, including carbon. Take an oil pan off of a car that has many miles on it and u will see metal shaving on the bottom of it. Jee I thought the oil filter was suppose to capture it .

Have u ever opened up an 'new' oil filter? Now have u ever opened up a used oil filter with 3K miles on it??? If u have u would see that there is far less media in a 3K oil filter than a new one. Sure some people out there are saying "duhhhh" well those are the same people that are runing oil filter to 5K or even 7.5K. So u think that a "good" oil filter can go up to 7.5K .
U know what I won't say anymore, just do me a favor and when u do ur next, or last (seems buy the way ur going) oil change take that oil filter to a hack saw. Check it out and then tell me waht u think. Oh and a few words of advise, when u do open up that oil filter. The media inside is not suppose to move around. The reason my urs would is because the media has shrunkin due to being used for 7.5K. Oh and if u wanna be real good to ur oil use those foam media filters, oh yea those will sure last up to 7.5K .


Ok true I would agree, to some degree. But the darkening of the oil is ovbiously due to buildup in carbon. Having 7.5K worth of carbon buildup in the oil is not a good thing. It doesn't matter what type of oil ur using there will be no change to the 7.5K worth of carbon flowing through the engine, oil passages, and combustion chamber. The only way to minimize the amout of carbon is to shorten the drain intervals.


Juker008

Juker008

Ahhhhhhhh...........no.


Juker008

Juker008

LMAO .
It is finial they will be on Wen.
I won't say more .


Juker008

Juker008

Yea and they also tell u to use Genuine Honda oil, oil filters, HondaTranny oil, Geunine Honda parts, Honda Paint, etc. , etc. .
Do ur own research and make ur own decisions. That way you will know that u found the "right" answer and that u know that u are doing the job right.


Juker008

JHEIII850Turbo

You wouldn't mind takin off those headers for that race, would ya?

I'd race you this Friday at Tower shopps, I'm going

russianDude

Well, its to much reasearch... but I've done some of it...
I will trust your expertise, do you think that it is safe to go with Mobil 1 oil & mobil 1 fileter 7,500 miles??? 50/50 city/highway

Juker008

Ahhhhhhhhh...........no.

3K all the way. No way an oil filter last past 3K.


Juker008

russianDude

But amsoil.com claims you can run their oil for 25K provided that you change their filter every 12.5K miles. They did chemical tests.


You are saying regular filter can not hold more than 3K miles, but what if you use Mobil 1 filter.

Juker008

No man . Do this, if u have now gone past a 5K oil change do an oil change, take ur oil filter and cut that bitch open with a hack saw. Now go do the same with the same with a new oil filter of the same make and model of the used one that u just cut open. U will see a FKin lot 'less' filter media in the used one compared to the new one.

And if u really wanna be scared go do the same to a filter with a 'foam' media. YEIKS!!! "Geeeee Juker008 where did the media go..." .

It doesn't matter if the filter is Mobil 1, STP, FRAM (a FKin joke), or whatever. Hell it could be made by Depends, Tampax, or Pampers (case we all know they are great on leaks) but they still won't last past 3K.


Juker008

russianDude

Sorry, I just don't buy that.... I can't belive that it is unsafe to drive past 3K with the best filter using synthetic oil. Mercedes recommend oil changes every 10K - 15 K miles, and those cars run forever. Filter color is not the only factor. If you really want to know whether your oil is good or not, you have to chemicly analyze your oil... Amsoil had some scientific proof that its oil is still good after 25K miles or 1 year.

Chemical testing of the oil will tell you right away if the oil is bad or good, if filters are bad as you say you will see this in oil results, but you don't!!

Juker008

UR right filter color is not the factor it is the filter media that is the factor. I have seen physical proof that filter meda doesn't survive long oil drain durations. At 3K the media has degraded quite a bit from what it was to begin with. Amsol says that their oil will survive to 25K, sure that is true. The oil hasn't lost its lubriscosity at that kind of duration. BUT U HAVE 25K MILES OF CARBON IN THE OIL. Listen man until u do ur own oil change, and look at the guts of what u consider the 'BEST' oil filter after 5K then come write to me . Sheeeesh I mean look at the previous posts to this forum.

While ur at it, after 25K of use on that Amsol stuff and u do an oil change. Be gutsy and take off ur oil pan I'm sure u'll find pretty shinny stuff adheared to the bottom of that oil pan. Oh and those shinny things are not a good sign. And a word of advice if u do have the intestinal fortitude to do so I honstly recomend replacing the oil pan gasket so that u don't have any leaks .

So go ahead if u wanna lubricate ur engine with 25K miles of carbon be my guest. I only care about the car, and I believe that every car has a soul, just don't let urs go to hell.


Juker008

russianDude

Well, I am also suspicious about 25K miles drain interval. I would never do it. But nowadays engines and oil quality is so much better than 20-30 years ago. "Change your oil every 3K miles" comes from old days when engines where not as clean, filters were not as good, and oil was not as good.

This ofcourse does not mean you can go 25K miles before changing oil... but I strongly belive that using synthetic oil and good quality filter you can at least go 6K miles...


I trust german engineers, and they recommend to change oil every 10K - 15 K miles on some of the most expensive Mercedes. They all use synethetic oil.


As far as color, yes, I do look at the color, and yes it gets dark after a while, but this does not necessarly means oil is bad.
I was reading some testimonials that peope where changing their synthetic oil every 5K miles and had their engines running without any wear at 200K miles.

Anyway, I think this topic is blown out of proportion. Sure, if you want to be extra carefull you shoud change it every 3K miles ( just in case ) but I consider this to be an overkill... if this gives you peace of mind, then by all means do it !
To me, according to all the research, you should be able to at LEAST double conventional 3K drain interval using synthetic oil and good quality oil filter.


Personally, I am little bit more concerned about our ransmissions

I have not seen any CLS engines breaking down yet

Technique

I change my oil every 15,000 miles, mobil 1 5w-30 and honda/acura factory filter.

russianDude

Do you drive a lot, mostly highway driving?

If you doing city driving you should change it sooner!!

Technique

Eh, I do a mix of 50/50 (city/hwy). I changed it first at 10,000 and the oil and filter were clean, so I changed again at 15,000 and they were still almost totally clean. I could probably go longer than 15,000 miles but I think it's about right.

Mercedes-Benz and BMW have on-board monitoring systems for the oil that measure the number of particles in the oil so the oil light that comes on is intelligent. My friends routinely average about 13,000-16,000 miles between oil changes in the V6 and V8 mercedes and BMWs. I figure that our honda engines are about as clean burning (if not cleaner) and that the manufacturing tolerances of the engine components are around the same quality level, so we shouldn't have excessive metal particles floating in our oil...

just my 2 cents

russianDude

You are very brave my friend, some of the member on this board will flame against you.
I am just doing 6K oil change intervals for 50/50 city/highway driving.

Technique

heheh, ya, I know some people on here change synthetic every 1500 miles or 3000 miles, but it's OK, I just don't have the time to do visit my dealer so much. Besides I am not planning on keeping my car past 200k miles anyway, I think it will be in a graveyard by that time, and every 15k miles for a synthetic oil change and I guarantee my engine will last until 200k miles...